“Do you see the absurdity of what I am? I can’t even express these things properly because I have to – I have to conceptualize complex ideas in this stupid limiting spoken language! But I know I want to reach out with something other than these prehensile paws! And feel the wind of a supernova flowing over me!” -Ronald Moore

Well, you probably don’t actually want to feel the wind of a supernova flowing over you; trust me on this.

Image credit: ESO / L. Calçada, of the remnant of SN 1987a.

But to find one for yourself, that’s definitely within your reach, if you know where to look.

Supernovae come in a few distinct types, two of which are far more common than others.

Image credit: STSCI, NASA; NASA/T. Strohmayer (GSFC)/D. Berry (Chandra).

There are Type Ia supernovae, the most common type of supernova in our own galaxy. These occur when a white dwarf star — either from mass siphoning, accretion, or mergers — reaches above a certain mass threshold. When this occurs, the atoms at the center of the stellar corpse can no longer remain stable, and a runaway nuclear explosion occurs. The result — as we’ve seen relatively recently in our galaxy — is a fantastic supernova explosion that destroys the previously existing star!

Image credit: NASA/ESA/JHU/R.Sankrit & W.Blair.

But these types of supernovae — the Type Ia — can occur anywhere where white dwarf stars are located. Given that these are the second most common stellar-type object (behind red dwarf stars) in the Universe, at least for the next few hundred billion years (after which they’ll eventually overtake red dwarfs), predicting where the next one will occur is a herculean task, well beyond what we know how to do.

But there is another type.

Image credit: Anglo-Australian Observatory, via Pete Challis.

When ultra-massive stars, or stars at least about eight times as massive as the Sun, exhaust the last of their nuclear fuel, the core of that star begins to collapse. Normally — and this happens in stars like the Sun — the forces between particles in the central region of the star are too strong for even gravity to overcome. This is true for nearly all classes of main-sequence star; our Sun is a run-of-the-mill G-class star.

Image credit: wikimedia commons user LucasVB.

But some stars are so massive — all of the main-sequence O-stars and the brightest of the B-stars — that the Pauli Exclusion Principle is insufficient to prevent core collapse, and this leads to a runaway reaction.

In the center of these stars, the core does in fact collapse, producing either a neutron star or black hole at the center, while the outer layers of the star are destroyed in a fantastic Type II supernova explosion!

But this is great, because it tells us something: if you want to find one of these Type II supernovae, you’re way more likely to get one if you look at a young, star-forming region of space!

Image credit: NASA,ESA, M. Robberto (STScI/ESA), HST Orion Treasury Project Team.

We have a few of these star forming regions in our own galaxy, of course, perhaps the most famous of which is the Great Orion Nebula, prominently visible during the winter months.

But you don’t mine for gold in a tiny vein when there are giant ones to go after, and you don’t look for supernovae in HII-regions of relatively quiet galaxies when there are places in space so active that the entire galaxy in question is a star-forming region!

Image credit: NASA / JPL-Caltech / STScI / CXC / UofA / ESA / AURA / JHU.

The easiest way to get a galaxy that forms stars this rapidly is when two relatively equal-sized galaxies merge. The gravitational interaction causes large amounts of the gas in both progenitor galaxies to contract down and form new stars. When this happens, the star formation rate can become tens, hundreds or (possibly) even thousands of times as great as it is in our own Milky Way.

While the vast majority of stars (99.9%+) created will be too low in mass to go supernovae, you don’t really care about that when you’re creating millions (or hundreds of millions) of stars. Eventually, one of them is going to blow.

Image credit: flickr user yu244720, a.k.a. (Robert) Sean Davies.

If you hear about it, and you know where to look, you can, of course, see it for yourself.

But if you’re really lucky, you can be the one looking at the right time to discover it! In fact, amateur astronomer supernova hunters can, individually, discover dozens of new supernovae on their own. The best place to look? You guessed it: merging and interacting galaxies!

Image credit: NASA, ESA, the Hubble Heritage Team and A. Evans.

These are the cosmic hotbeds of star formation, and hence they’re also the most prolific cosmic supernova factories. But looking at any one galaxy in particular, just once, isn’t going to tell you very much. (Even if it’s one of the most active galaxies in the entire known Universe.)

Image credit: NASA/ESA/Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration.

That’s because what you need to do is find a galaxy and compare it to earlier images of that same galaxy. It’s only when you get an unexpected brightening — a rapid, extreme brightening — that rises and falls over the span of many days, that you’ve got a candidate for a supernova.

And if you find one, that only means you’ve got a candidate supernova. For confirmation, you need spectroscopic follow-up, and that almost always requires the attention of a professional.

Image credit: NASA / JPL-Caltech / STScI-ESA / S. Bush, et al. (Harvard-Smithsonian CfA).

This Hubble/Spitzer composite image shows the mammoth galaxy NGC 6240, an ultraluminous galaxy in the process of a major merger. Recently, astronomy outreach expert Adam Block took this spectacular wide-field image of this galaxy. The sight is spectacular, and (like for all images here) you can click for a full-resolution image in all its majesty.

Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona.

Even though this galaxy is certainly undergoing higher-than-average rates of star-formation, it certainly isn’t obvious that anything out-of-the-ordinary has happened here.

But something’s worth checking out. Let’s take a look at the highest-resolution Hubble image available of this galaxy, and in particular, I want you to focus on the star-forming region I’ve outlined in orange, below.

Image credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University).

This region is one of the hotbeds of star-formation. I mean, the whole galaxy is, but the blue reflection nebula tells you that there are some extraordinary hot, blue stars in there, as well as some neutral gas/dust, which reflects the light from those hot, blue stars.

The thing is, that image is from years ago. Let me take you inside Adam Block’s image, now, and see if you can find anything interesting.

Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona.

Look hard, detectives. Let me help you out, with a little zooming, cropping, and a couple of arrows.

Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona (bottom), NASA / ESA / Hubble Heritage Team / A. Evans (top).

That has got to be a supernova! It’s almost definitely a Type II, based on where it’s happening, and even though it’s probably a rather uninteresting one now that it’s almost certainly on the decline (I believe the image dates from April 11th), if you happen to be a professional out there just twiddling your thumbs with clear skies and no targets of interest, take a spectrum of this and give Adam Block, who’s created some of the most spectacular astroimages I’ve ever seen, his first supernova discovery!

Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona.

And if you happen to be looking — with the right equipment, in the right place, at the right time — you, too, could find one of these for yourself!

“Because dark energy makes up about 70 percent of the content of the universe, it dominates over the matter content. That means dark energy will govern expansion and, ultimately, determine the fate of the universe.” -Eric Linder

It’s been a while since we’ve spoken about dark energy, and we were just talking about Einstein’s greatest blunder, so let’s just dive right in.

Image credit: S. Beckwith & the HUDF Working Group (STScI), HST, ESA, NASA.

This is our observable Universe, as unveiled by the Hubble Space Telescope. With hundreds of billions of galaxies stretched out some 41 billion light years in all directions, finding out about what our Universe was like in the distant past, the recent past, and what it’s like today is limited only by our willingness to look. In particular, there are three great sets of observations that tell us ever so much about the Universe on the largest scales.

Image credit: Northern Galactic Cap from the SDSS-III release, via http://www.sdss3.org/.

1.) The way galaxies cluster together on the largest scales. By looking at huge, tremendous surveys of galaxies, we can see how the visible matter in the Universe has clustered, clumped, and grouped together, as well as where it hasn’t, and has left us great cosmic voids. By putting various ingredients into a model Universe governed by General Relativity, we can also simulate how structure should form in our Universe. Where the simulations and the observations match up, that tells us what’s in our Universe.

Image credit: ESA and the Planck Collaboration.

2.) The temperature fluctuations in the cosmic microwave background. By looking at the temperature fluctuations — the hot-and-cold spots — in the CMB, we can know what the Universe looked like in terms of overdensities, underdensities, and how they’re clustered with respect to one another all the way back at a time when the Universe was just some 380,000 years old! Because the light has had to travel for nearly the entire 13.8 billion years that the Universe has been around (it’s been traveling for 99.997% of the Universe’s history), we can find out information about what the Universe was like back then, but also how it’s expanded since then. This pattern of fluctuations also tells us what the various combinations of ingredients are in our Universe.

Image credit: Kowalski et al., Ap.J., 2008.

3.) Direct observations of well-understood objects at various distances/redshifts in the Universe. Everything from variable stars to properties of galaxies to distant supernovae help us get a handle on this, the cosmic distance ladder. This tells us how the Universe has been expanding since as far back as we can measure until the present day.

When these three data sets are combined — and we can combine others, too, but these three are the best data sets we have — they tell us that there’s matter in the Universe, about 31-32% of the Universe is matter (most of which is dark matter), and that there’s another type of energy, dark energy, that makes up the rest.

Image credit: Planck Collaboration: P. A. R. Ade et al., 2013, A&A Preprint; annotations by me.

So, you ask, just what is dark energy, and how do we know?

In principle — and by in principle, I mean in General Relativity — matter, energy, topological defects, and pretty much anything else that you throw into your Universe is going to affect how your Universe expands because of two properties inherent to it: it’s energy density and its pressure.

Image credit: Large Synoptic Survey Telescope, NSF, DOE, and AURA.

Because of the way the Universe is observed to expand, and because of the known way that matter (yes, even dark matter, according to General Relativity) behaves, we can infer something about the energy density and pressure of dark energy. In particular, we know that dark energy’s pressure is negative, and that it’s quite negative.

In General Relativity, we can relate the pressure of any component of the Universe to its energy density by the simple equation:

ρ = w P / c²,

where ρ is the energy density, P is the pressure, c is the speed of light, and w is just some number.

Image credit: A.V. Vikhlinin, R.A. Burenin, A.A. Voevodkin, M.N. Pavlinsky.

According to the best data we have right now, w is equal to -1. Now, as time goes on, we hope to constrain it better; we can say it’s probably about -1.00 ± 0.08 right now, which is pretty good.

Now, here’s the thing: in theory, the pressure of different things in cosmology goes in increments of 1/3. For example:

• Radiation has w = +1/3, like photons and ultra-relativistic matter.
• Matter, both normal and dark matter, has w = 0, or is virtually pressure-free.
• Cosmic strings, or 1-dimensional topological defects, have w = -1/3. This is the border between what would cause a Universe to accelerate (more negative than this) or not.
• Domain walls, or 2-dimensional topological defects, have w = -2/3.
• A cosmological constant (or textures, a 3-d defect) has w = -1.

Those are the easy possibilities.

Image credit: NASA / CXC, via http://chandra.harvard.edu/.

But dark energy could also be something weird. It could be a field, whose relationship between pressure and energy density changes over time. It could be coupled to something we don’t understand. It could be really, really weird, and our measurements of w = -1, to the best we can see, could only be what the Universe is so far.

So we’ve attempted to look for a change in w over time. We’ve attempted to look for departures from w = -1. We’ve attempted to look at different models and their signatures.

Know what we’ve found?

Image credit: Pearson / Addison-Wesley.

The farther back into the past we look, the more and more consistent everything appears to be with the cosmological constant option.

The cosmological constant option has the theoretical bonus of being:

• easily explained,
• inevitable (in that it must exist, even though its value could be 0),
• and requires no new physics beyond the standard model/GR to explain.

We’re going to keep exploring different variants of dark energy, quintessence, scalar field-driven dark energy, etc., of course. But theoretically, there’s no motivation unless we see some sort of evidence that tells us that dark energy is something more (or other) than a simple cosmological constant. And trust me, we’re looking.

Image credit: LSST and others, via http://www.lsst.org/lsst/science/scientist_dark_energy.

This doesn’t mean dark energy is a cosmological constant, it just means that this is the best working hypothesis until evidence suggesting otherwise comes along, and such evidence does not exist today. That’s the best we’ve got, so far.

“Science literacy is a vaccine against the charlatans of the world that would exploit your ignorance.” -Neil deGrasse Tyson

Well, I guess it’s that season again. The charlatan who claims to have invented a cold fusion device — the same device whose flaws were exposed here two years ago — has just held an “independent test” of his device, and there’s now a physics paper out claiming that this device works, and must be powered by some type of nuclear reaction!

Image credit: G. Levi et al.; get the whole paper here: http://arxiv.org/pdf/1305.3913v2.pdf.

Well.

Look, let’s get a few things out into the open first. If there is a cold fusion device that actually works, that can harness the power of nuclear fusion to create energy, it would change the world. We would — as I’ve written recently — have a virtually limitless source of clean and cheap energy, and would not only be able to travel to Mars, but to any other world in our Solar System. We could even, literally, reach for the stars!

Image credit: OeWF (Katja Zanella-Kux), via http://www.wired.co.uk/.

But it’s not enough to just simply think about how wonderful it would be if it were true, especially because whether cold fusion can even physically happen in our Universe is currently an open scientific question. (The evidence so far says no, but that doesn’t mean it isn’t possible in principle!)

What we must do, when confronted with a claim that’s this extraordinary — that we have a device, at low-temperature, with neutral atoms, fusing atomic nuclei — is demand evidence that shows this is really true, and that we aren’t falling victim to some elaborate ruse.

Image credit: John Cooke, of “Piltdown Man”, one of history’s most elaborate scientific hoaxes.

What we need, if we want to take this claim seriously, is solid, incontrovertible evidence that what’s being claimed is what’s actually happening. Because one of the most important responsibilities that science has to society is to protect it from frauds, hucksters, shysters and con artists who would defraud you out of your money, time, and trust with their cheap trickery and chicanery.

Image credit: Rossi, Kullander, Essen and the e-Cat, retrieved from energydigital.com.

I’m taking it for granted that the vast majority of you don’t have the required expertise to tell whether this is legitimate, or whether this is an example of someone trying to swindle you (and all of us) into investing in something that’s meritless. But a lot of normally smart people are getting very excited about this, including:

• Sebastian Anthony over at ExtremeTech,
• Francie Diep over at Popular Science,
• Mark Gibbs over at Forbes, and shockingly,
• Tommaso Dorigo of Quantum Diaries.

So we’ve got to ask, is this test the real deal, or is it nothing more than crackpottery, as Lubos Motl says?

Image credit: from the Nov. 12, 2012 testing of the E-Cat, via G. Levi et al.

Let’s answer the following question: What would it take to convince a reasonable observer that you’ve got a controlled nuclear reaction going on here?

There are a few ways we could do it:

1. Allow a thorough examination of the reactants before the reaction takes place, and another of the products after the reaction, and show that nuclear transmutation has in fact taken place.
2. Start the device operating by whatever means you want, then disconnect all external power to it, and allow it to run, outputting energy for a sufficiently long time in a self-sustaining mode, until it’s put out a sufficient amount of energy to rule out any conventional (i.e., chemical) energy sources.
3. Place a gamma-ray detector around the device. Given the lack of shielding and the energies involved in nuclear reactions, gamma-rays should be copious and easy to detect.
4. Accurately monitor the power drawn from all sources to the device at all times, while also monitoring the energy output from the device at all times. If the total energy output is in sufficient excess to the total energy input to rule out any conventional (i.e., chemical) energy sources, that would also be sufficient.

Fair enough? These all sound reasonable to me, and I would accept any independent test of these three methods as enough evidence to pique my interest. Let’s see what the claims are.

Image credit: G. Levi et al.

So they’re again claiming that this is nickel + hydrogen fusion, which should result in copper. Now, it’s important to know, the last time this was claimed, the nickel that was analyzed was found to contain the isotopic ratios of normal nickel mined on Earth, while the copper (10% of the product) was found to contain the isotopic ratios of copper found naturally on Earth, not the ratio you’d expect to find copper in if nuclear fusion had occurred! (Since only Nickel-62 and Nickel-64 can fuse with hydrogen into copper, it’d be impossible to get a 10% copper product in any case!)

Image generated using the free graphing software at nces.ed.gov.

For this test, Rossi disallowed the examination of either the reactants or the products, claiming that it would reveal his secret catalyst. So option 1 wasn’t available.

Rossi also refused to unplug the machine while it was operating! Now, Peter Thieberger (who co-wrote this post with me, and who is a respected nuclear/particle physicist) has demonstrated just how easy it would be to keep power flowing to a device in such a way to fool an ammeter, which is a device for measuring electrical current. In other words, it would show that no current was flowing when one actually was!

Image credit: Peter Thieberger.

So option 2 wasn’t available, either; there could’ve been more power continuously supplied to this setup than was accounted for.

There was also no attempt made to measure gamma-rays, so option 3 didn’t happen. Reading the paper, Rossi left the machine plugged in at all times, and hid a great many details during this independent test. Such as:

“… the E-Cat HT was already running when the test began…”

“…it was not possible to inspect the inside of the control box…”

So, what did this team actually do?

Image credit: Figure 6, from G. Levi et al.

They measured the tube, from a distance, with an infrared camera, to determine its temperature over time. They claim to have set up radiation detectors at a distance to look for high energy photons, but do not include those results. (They say that the results are available upon request. If you get them, please post them in the comments!)

They claim that the input power is well-measured and comes out to an average of 360 Watts, over a timespan of around four days. They provide no data for this, they simply claim it. What can you do; are they telling the truth, are they telling the truth as best as they know it, or something else? Without the data, how can you know?

Image credit: Figure 14 from G. Levi et al.

Well, the short of it is, it got very hot and stayed very hot — about three-to-seven times hotter than you’d expect based on 360 W of continuous power — for the entire time that it ran.

And then, when you get all the way to page 20, you find this red flag:

During the coil ON states, the instantaneous power absorbed by the E-Cat HT2 and the control box together was visible on the PCE-830 LCD display. This value, with some fluctuations in time, remained in any case within a range of 910-930 W. By checking the video image relevant to the PCE-830 LCD display, we were also able to estimate the length of the ON/OFF intervals: with reference to the entire duration of the test, the resistor coils were on for about 35% of the time, and off for the remaining 65%.

So… it wasn’t a continuous 360 Watts, but rather there was a switching between on/off states, where it was drew over 900 W of power for about a third of the time, and then far less for the other two-thirds. They also only approximate, rather than measure (or provide data for) the amount of power drawn.

Then they claim the following:

Image credit: page 22 of G. Levi et al.

Okay, look.

I’m done pretending that this is science, or that the “data” presented here is scientifically valid. If this were an undergraduate science experiment, I’d give the kids an F, and have them see me. There’s no valid information contained here, just the assumption of success, the reliance on supplied data, and ballpark estimates that appear to be supplied “from the manufacturer.”

This is not a valid way to do science at all. And this is certainly not even close to meeting the criteria required for extraordinary evidence to back up such an extraordinary claim.

Image credit: Hemant Mehta of the Friendly Atheist blog.

I — for once — will also encourage you to read Lubos’ take on this, because he seems to be the only person other than me who recognizes what awful pretend-science this is.

I’m not trying to rain on your parade, I’m not trying to poo-poo things we don’t have a full understanding of, and I’m not even trying to convince you that cold fusion is impossible. I’m trying to get you to recognize that there are standards of evidence you must hold these claims to, and that this crappy, crackpot paper has failed to meet them, and has failed egregiously.

But if you test it scientifically, then we’ll talk. Not before. Until then, you’re just preying on people who don’t know enough physics to see through your ruse, and I’ll be here to speak up against it, and call shenanigans.

Image credit: from Ebaumsworld; bonus points if you recognize the source.

Shenanigans, bitches. Now you know.

“The Milky Way is nothing else but a mass of innumerable stars planted together in clusters.” -Galileo Galilei

Welcome back to another Messier Monday here on Starts With a Bang! With 110 deep-sky objects making it up, the Messier Catalogue is the first comprehensive, accurate catalogue of faint (but not too faint) fixtures in the night sky. Each object tells its own unique tale, and is visible to amateur and professional skywatchers alike with even the simplest of equipment. Many of these objects were discovered by Charles Messier himself (or his assistant, Pierre Méchain), while others go all the way back to antiquity!

Image credit: SEDS compilation of all 110 Messier objects, via http://messier.seds.org/.

Today, we’re taking a look at just the fifth object in his catalogue, the globular cluster Messier 5. Discovered in 1702 by Gottfried Kirch and Maria Margarethe, it’s a collection of some 100,000 stars contained within a radius of around 100 light years, like all globular clusters. However, Messier 5 is unlike the majority of globulars for a number of reasons, which you can marvel at every time you take a look at it. Here’s how to easily find this wonder of the night sky.

Image credit: Me, using the free software Stellarium, via http://stellarium.org/.

The brightest star in the northern hemisphere, Arcturus, is one of the easiest to find: just follow the “arc” of the Big Dipper’s handle and you can’t miss this orange giant! You can “speed on” to Spica, a bright blue star, and find yellowish Saturn just a few degrees away for the rest of the year. But if you look to the left of Arcturus and Spica, you’ll find a fainter but still bright star called Unukalhai (or α Serpentis), the brightest star in the constellation of Serpens.

If you look back towards Spica a few degrees, you’ll see the faint, naked-eye star 5 Serpentis, and if you train your binoculars or telescope on that star, you can’t miss Messier 5, less than half-a-degree away.

Image credit: Me, using Stellarium.

Being a globular cluster, M5 looks like a dense, fuzzy ball that’s brighter towards the center and gradually fainter the farther you move away from the core. Like most globulars, it’s very old — more than 10 billion years for certain and possibly up to 13 billion, as dated from its Hertzsprung-Russell diagram — and metal-poor, with its stars containing less than 10% of the elements heavier than hydrogen and helium that the Sun has.

Image credit: Eduardo Mariño, via his flickr photostream.

But unlike most globulars, there are virtually no bright stars in M5; the brightest star in there is only of magnitude 12.2, meaning that (realistically) you need at least a 6″ (15 cm) telescope to actually tell that this fuzzball is made of stars! Messier himself wrote that it’s a round nebula that doesn’t contain any stars, which is exactly what I see with my own equipment.

But even many casual amateurs have far better equipment than Messier did in the latter-half of the 18^th Century.

Image credit: CN member 2020BC, via Charlie Hein of http://www.cloudynights.com/.

There are a number of features that make this globular cluster really stand out:

1. It’s very close (20′ to be precise) to a naked-eye star, something that’s true for only a small minority of deep-sky objects,
2. It’s got a very dense nucleus where individual stars become very difficult to resolve, and yet also is a very extended globular cluster, with a radius approaching 200 light-years,
3. And, as you may have already been able to tell (but it’s abundantly clear in the image below), this cluster is ellipsoidal, rather than spherical!

See for yourself!

Image credit: Robert (Bob) J. Vanderbei of Princeton University.

Because this globular cluster is — like most globulars — so old, the very bright blue stars you can see are blue stragglers, or stars that were created relatively recently from the merger of smaller stars, and the bright yellow/orange stars are Sun-like stars that have evolved into giant stars, something that will be our star’s fate when it’s as old as Messier 5 is now!

But what you might not realize is that this globular cluster is full of a special class of low-mass variable stars known as RR Lyrae stars. What you see actually depends slightly on when you look!

Image credit: Robert (Bob) J. Vanderbei of Princeton University, once again.

With at least 105 known variable stars in it, Messier 5 is one of the most prolific globular clusters in this sense! It’s also one of the larger ones, with some estimates of the total number of stars in M5 reaching 500,000! (This makes sense, since one out of every few thousand stars is known to be a variable-type star.) It’s located a distance of 25,000 light-years away, moving away from us at about 52 km/sec.

Image credit: © 2006 – 2012 by Siegfried Kohlert of http://www.astroimages.de/.

The closer you can look into the core, the higher the concentration of blue stars becomes. This is a relatively common feature in globular clusters, as mergers and mass-transfer becomes more common in the densest regions of a cluster. This beautiful image by Adam Block really showcases just what’s going on in terms of star color and how it changes with radius.

Image credit: Adam Block, Mt. Lemmon SkyCenter, University of Arizona.

As always, however, the best image of the core of this globular cluster comes from the Hubble Space Telescope, whose resolving power is really unparalleled when it comes to separating out individual stars in dense, distant regions. The central core here is only 6 light-years in diameter, or just 50 arc-seconds across as seen from our point-of-view.

Image credit: ESA / Hubble & NASA.

Because I’m a sucker for it, let’s take a full-resolution trip through the inner core of Messier 5, just to show you how spectacularly (and how quickly) the star density rises-and-falls as you pass through the very central region!

Image credit: ESA / Hubble & NASA.

Remember, there are 29 globular clusters in Messier’s catalogue and some 200 total in the halo of our galaxy, but each one is a unique collection of ancient stars with its own history, and I’m pleased to get to share this one with you today, on Messier Monday!

Including today’s entry, we’ve taken a look at the following Messier objects:

• M1, The Crab Nebula: October 22, 2012
• M5, A Hyper-Smooth Globular Cluster: May 20, 2013
• M8, The Lagoon Nebula: November 5, 2012
• M13, The Great Globular Cluster in Hercules: December 31, 2012
• M15, An Ancient Globular Cluster: November 12, 2012
• M20, The Youngest Star-Forming Region, The Trifid Nebula: May 6, 2013
• M25, A Dusty Open Cluster for Everyone: April 8, 2013
• M30, A Straggling Globular Cluster: November 26, 2012
• M33, The Triangulum Galaxy: February 25, 2013
• M37, A Rich Open Star Cluster: December 3, 2012
• M38, A Real-Life Pi-in-the-Sky Cluster: April 29, 2013
• M40, Messier’s Greatest Mistake: April 1, 2013
• M41, The Dog Star’s Secret Neighbor: January 7, 2013
• M44, The Beehive Cluster / Praesepe: December 24, 2012
• M45, The Pleiades: October 29, 2012
• M48, A Lost-and-Found Star Cluster: February 11, 2013
• M51, The Whirlpool Galaxy: April 15th, 2013
• M52, A Star Cluster on the Bubble: March 4, 2013
• M53, The Most Northern Galactic Globular: February 18, 2013
• M60, The Gateway Galaxy to Virgo: February 4, 2013
• M65, The First Messier Supernova of 2013: March 25, 2013
• M67, Messier’s Oldest Open Cluster: January 14, 2013
• M72, A Diffuse, Distant Globular at the End-of-the-Marathon: March 18, 2013
• M74, The Phantom Galaxy at the Beginning-of-the-Marathon: March 11, 2013
• M78, A Reflection Nebula: December 10, 2012
• M81, Bode’s Galaxy: November 19, 2012
• M82, The Cigar Galaxy: May 13, 2013
• M83, The Southern Pinwheel Galaxy, January 21, 2013
• M92, The Second Greatest Globular in Hercules, April 22, 2013
• M97, The Owl Nebula, January 28, 2013
• M102, A Great Galactic Controversy: December 17, 2012

Come back next week, where we’ll take a look at one of the rare “late additions” to Messier’s catalogue and explore another one of these deep-sky wonders, only here on Messier Monday!

“I prefer to be true to myself, even at the hazard of incurring the ridicule of others, rather than to be false, and to incur my own abhorrence.” -Frederick Douglass

I thought we were past this, I really did. Having grown up in New York, having lived in eight different states and traveled to 39 others — as well as maybe a dozen different countries — I truly thought there were a few things that were obvious. One of them, of course, is that you’ve got to give something a shot to know whether you like it or not. Hopefully, no matter who, where, or what you are, you’ll enjoy this upbeat song by Bob Schneider as much as I do, so have a listen to

Mudhouse.

Another, even more fundamentally simple and obvious one, is that people are individuals, and ought to be judged solely on their merits as individuals. You might be tempted to make generalizations about someone based on your preconceptions about their race, their gender, their country-of-origin, their sexual orientation, etc., but at the end of the day, each one of us is an individual.

And in no way — to me, at least — is that more obvious than when it comes to studying the Universe.

Image credit: Tanja Sund of http://astrotanja.com/.

Which brings up my point: do you think race, gender, or ancestry determines who can or cannot succeed in a given career?

If the answer isn’t a swift and immediate “of course not” for you, congratulations, you might be a scientific racist! I would’ve thought this had gone out of fashion after World War II, and I certainly didn’t think I’d encounter it ever in my lifetime. In a famous statement all the way back in 1950, UNESCO had the following to say:

The biological fact of race and the myth of ‘race’ should be distinguished. For all practical social purposes ‘race’ is not so much a biological phenomenon as a social myth. The myth of ‘race’ has created an enormous amount of human and social damage. In recent years, it has taken a heavy toll in human lives, and caused untold suffering.

And yet, here we are, studying things like gender-and-math-aptitude or IQ-and-race like these are actual sciences.

Image credit: Wikimedia commons user Quizkajer.

There are some of you out there who have no idea why this is offensive, why this isn’t science, and why this is racist.

Let me try to put this in perspective for you.

How do you feel when you see unequal treatment, based on race, in situations such as this?

Image credit: Alexandra Dal of http://alexandradal.tumblr.com/.

Do I need to explain to you why this is offensive, why this is racist, or why this is grossly unfair treatment? Do I need to explain to you that the person on the left and the person on the right in each case deserve to be treated equally, regardless of what any test, statistic or study has said about outcomes?

Here’s why, for those of you who need the explanation: Every person in this world deserves to be treated with the dignity and respect that we, ourselves, would like to be treated with.

The idea that tests like an “IQ Test,” the “SATs” or the “GREs” are somehow indicators of what races or genders are better suited to certain types of careers are meritless, not borne out by evidence, and also incredibly offensive. And yet, you can apparently get a Ph.D. in this from Harvard.

Image credit: screenshot from Jon Wiener’s blog at http://www.thenation.com/.

This. Is. Not. Okay.

People have been using studies like this to argue about genetic inferiority for centuries, contending that some races are genetically inferior, the female gender is inferior at math, and that this makes them ill-suited to careers that involve heavy amounts of math/science/detail-oriented work.

And yet, if you’ve ever gone to school or met a substantial number of human beings of any race, gender, or ancestry, that notion seems like utter lunacy. It’s as plain to me as it was to Charles Sumner nearly 200 years ago.

Image credit: Theoretical Particle Physics at SISSA, via http://www.sissa.it/tpp/.

Everyone should be not only allowed but encouraged to pursue their interests and passions, and should be granted the opportunity to develop their skills and do their best. We have a terrible track record of denying women their deserved place in scientific history, and despite the incredible successes of women and people of color in all sorts of arenas of life, we still stereotype that somehow, white (and maybe asian, too) men are simply innately better-suited to becoming scientists.

After all, you’ve probably heard the story of Carl Sagan’s first encounter with science when he was a boy, when he received a toy robot:

But the most fascinating things about this, was a panel you could take off the side of it, and you could actually see inside, all the gears and all the workings inside. After that, I was hooked. I had to see how all these things worked. I was always in competition with my… brother, to find out who could be the smartest, who knows the most about how everything worked.

Except I lied to you. That’s not Carl Sagan’s story; it’s Vincent Rodgers’ story!

Image credit: University of Iowa, via http://siena.cs.uiowa.edu/~vrodgers/.

The idea that someone would be denied the opportunity to pursue their dream career for any reason other than their own individual merits is absolutely bigoted, and always wrong.

So this week, I was heartened to come across something simple and straightforward being done to fight this evil, but almost no one has heard about it. Let’s change that together; allow me to introduce to you Scholars Against Scientific Racism.

Image credit: Scholars Against Scientific Racism.

Rather than focus on the latest egregious offense in this vein, let’s focus on ending this garbage once and for all. There’s a simple google document (I tested it, there’s no malware or anything) that you can sign your name to to say that this line of thinking has no scientific merits when it comes to crafting public or social policy, and does not deserve to be studied as though it does. Let’s get the racism, sexism and bigotry out of science once and for all, and we can start by fighting against this garbage:

Dean Ellwood at Harvard Kennedy School takes the position that this dissertation is part of an academic debate. We are not against academic freedom. However, there is no academic debate on whether or not Hispanics as a group are less intelligent than native-born whites. There are debates on whether or not Hispanic is a pan-ethnic, ethnic, or racialized category. There are debates on how and whether or why we should measure intelligence. There are debates on the extent to which intelligence is a heritable trait. But, there are no debates on whether or not Latino immigrants have the intellectual caliber to be part of the United States. Those kinds of debates happen in nativist and white supremacist circles, which have no place in academia, which prizes arguments and debates based on valid constructs and scientific evidence.

It’s not science, and it’s not right. Let’s do our part to make sure that people are judged on their merits as people, nothing less and nothing more.

“Anyone who has never made a mistake has never tried anything new.” -Albert Einstein

Back when Einstein first proposed his theory of General Relativity, his revolutionary picture of the Universe was met with a mix of curiosity, awe, and intense skepticism. It isn’t every day that your most cherished of all physical theories — the theory of Newtonian Gravity that had ruled the cosmos for nearly two-and-a-half centuries — gets challenged by a newcomer.

Image credit: Brooks/Cole – Thomson publishing, 2005.

And yet, that’s exactly what Einstein did when he proposed General Relativity at the end of 1915, nearly a century ago. Newtonian gravity, according to Einstein, was just an illusion. Objects didn’t really exert gravitational forces on one another, which in turn caused accelerations/changes in momentum, but rather the entire Universe existed in a framework known as spacetime, and the presence of matter-and-energy curved the fabric of that spacetime, causing objects to move as they do.

Image credit: WGBH Boston, retrieved from http://www.ast.cam.ac.uk/.

Einstein’s theory not only reduced to Newtonian gravity when gravitational fields were weak, it also predicted the orbital anomaly of Mercury, something that had puzzled astronomers and physicists alike for nearly 50 years. When the 1919 eclipse was observed, and distant starlight was observed to have bent in agreement with General Relativity (and not in agreement with any interpretation of Newton’s laws), our picture of the Universe was revolutionized.

Image credit: 22 November 1919 edition of the Illustrated London News.

Before any of this happened, however, Einstein was very much bothered by an aspect of his theory. You see, it was assumed at the time that the Universe was made up of stars, whose distribution was relatively uniform throughout space. This was furthermore assumed to be stable, and not something that had either changed much with time or that was likely to change into the far future. The stars were assumed to be long-lived, and evenly distributed around us in all directions.

Image credit: Bill Keel of University of Alabama, via http://www.astr.ua.edu/.

In general, this type of solution presented a grave problem for Einstein: it is an unstable solution! If you have a roughly (but not perfectly) uniform distribution of matter, then spacetime is going to curve due to the presence of that matter. And once spacetime is curved, those regions with slightly more matter than others are going to preferentially attract more and more matter, and will grow over time!

What’s even worse is that the fate of all such configurations of mass like this, regardless of what shape they start off in, wind up creating a black hole!

Image credit: “Black Holes: Portals into the Unknown”, © 1997-2001 Benjamin, via http://library.thinkquest.org/.

This clearly isn’t the case for our Universe! And Einstein knew this wasn’t the case for our Universe, so what was actually happening?

The laws of gravity weren’t lying, but there must’ve been something that wasn’t properly accounted for. As far as Einstein could tell, stars pretty much stayed where they were over time, and extended out maybe on the order of thousands of light-years in all directions. Because they weren’t all collapsing towards a point or region, Einstein reasoned that there had to be something fighting gravity on these large, interstellar scales.

Image credit: Natalie Roe for the SNAP collaboration, via http://snap.lbl.gov/.

He proposed that there was an intrinsic energy to space itself, a cosmological constant, responsible for this. This cosmological constant would push back with exactly the force needed to counteract gravity on these large scales, and would lead to the Universe being static.

Now, we can fast-forward almost 100 years, to our modern picture of the Universe.

Image credit: ESA and the Planck Collaboration.

The Universe is not, in fact, static, but has been expanding for billions of years. What Einstein missed is that our Universe extends far beyond our own galaxy, and in fact contains many hundreds of billions of galaxies comparable to our own. This wasn’t discovered observationally until years after General Relativity was proposed, so Einstein could hardly be faulted, and yet he was frustrated at himself for not finding the solution in General Relativity that admits an expanding Universe. Perhaps apocryphally, he’s credited with calling his introduction of the cosmological constant his “greatest blunder.”

Had he found the solutions later found by Friedmann, Lemaitre, Robertson and Walker, he might have proposed that the Universe was expanding, and never suggested the ad hoc cosmological constant at all.

Image credit: S. Perlmutter et al. (Supernova Cosmology Project).

And yet, since the late 1990s, we’ve realized that the Universe does in fact have a non-zero cosmological constant: that’s what we call dark energy, and use to explain the accelerated expansion of the Universe!

Image credit: NASA.

You might think that, because the cosmological constant does turn out to exist, and be non-zero, and because there is an intrinsic energy to space itself, that perhaps Einstein didn’t make a mistake after all.

Nothing could be further from the truth. In physics, we propose novel theoretical mechanisms to both explain observed phenomena and to predict new, hitherto unobserved phenomena. That’s what theoretical physics is all about.

And I hate to break it to you, but Einstein’s cosmological constant utterly failed on both of those counts.

Image credit: Sheldon Faworski and Sean Walker, via http://www.astropix.com/.

Not only did he not successfully explain why the stars in our galaxy remain in a roughly stable configuration — because they’re in quasi-stable orbits around the galaxy — but he also failed to predict the phenomena of the expanding Universe.

Had he gone with the expanding Universe solution instead of the cosmological constant solution to the problem of a Universe that hadn’t yet collapsed into a black hole, that would’ve been correct.

Image credit: retrieved from http://izquotes.com/.

Einstein, to his great credit, was smart enough to admit to himself, and to the world, that his solution was not the right one.

Even today, looking back and recognizing that there is, in fact, a cosmological constant / dark energy component to the Universe, Einstein was still wrong!

It isn’t enough to get the right answer in physics, or in science in general. You need to get the right answer for the right reasons, otherwise you are doomed to lead yourself astray.

Image credit: Sean Carroll, via Steve Hsu of http://infoproc.blogspot.com/.

The cosmological constant may have come back, but it has nothing to do with the reasons Einstein proposed for its existence, nor is it of anywhere near the same magnitude that Einstein suggested. Sometimes old ideas come back in new forms to solve new puzzles.

Why do I tell you this? Because it’s tempting to revise history, to make our heroes even more heroic and to give them credit for discoveries that they themselves did not make. It’s also all too easy to fool ourselves, and to discount our own actual mistakes because there was a somewhat-related success down the road.

Image credit: European Space Agency.

It’s okay to be wrong; being wrong is evidence that you were trying, and also evidence that you were honest with yourself. The important thing is to get it right in the end. We’re going to be wrong about an awful lot of things going forward; of that I’m certain.

What will separate those of us who are good scientists about it will be our willingness to let go of ideas that no longer agree with the data, admit we were wrong, and embrace the theoretical ideas that are in accord with what we observe. We may even wind up reviving old ideas and finding new ways that they apply to our Universe as we learn more about it. (It doesn’t mean the old ideas were right all along, though!)

This is science, where every day we come a little closer to getting it right. Thanks for coming along on the journey with me.

“Supposedly she’d died, but here she was again–somewhat changed, but you couldn’t kill her. Not when the truest part of her hadn’t even been born.” -Denis Johnson

Over the past 100 years, our picture of the Universe has changed dramatically, on both the largest scales and the smallest.

Image credit: Richard Payne.

On the large-scales, we’ve gone from a Newtonian Universe of unknown age populated only by the stars in our own Milky Way to a Universe governed by General Relativity, containing hundreds of billions of galaxies.

Image credit: Rhys Taylor, Cardiff University.

The age of this Universe is dated at 13.8 billion years since the Big Bang, the observable part of which is some 92 billion light-years in diameter, filled with normal matter (and not antimatter), dark matter, and dark energy.

On the small scales, the revolution has been just as dramatic.

Image credit: 2011 Encyclopaedia Britannica.

We’ve gone from a Universe made up of atomic nuclei, electrons and photons, where the only known forces were gravitational and electromagnetic, to a much more fundamental understanding of the smallest particles and interactions that make up the Universe. Nuclei are made up of protons and neutrons, which — in turn — are made up of quarks and gluons. There are two types of nuclear forces, the strong and the weak forces, and three generations of particles, including the leptons (electrons, neutrinos, and their heavier counterparts) and quarks (up, down, and their heavier counterparts). There are gauge bosons governing the strong, weak, and electromagnetic forces, and finally there’s the Higgs, bringing this all together under the framework of the Standard Model.

Image credit: Fermilab, modified by me.

And combining the Standard Model of particle physics with General Relativity and the standard model of modern cosmology means that we can nearly explain the entire physical Universe! By beginning with a Universe that had slightly more matter than antimatter, and starting just some 10^-10 seconds after the Big Bang, we can account for all of the observed phenomena using only the already-established laws of physics. We can reproduce — with simulations — a Universe that is, in all meaningful ways, physically indistinguishable from our own.

Images credit: 2dF Galaxy Redshift Survey (blue) and Millenium Simulation (red), which agree!

And yet, there are some very fundamental questions we still don’t understand. Among them are:

1. Why is there more matter than antimatter? Where did the asymmetry (of the observed magnitude) come from?
2. What is the nature of dark energy? What is the field/property responsible for it?
3. What is the nature of dark matter? What is the particle responsible for it?
4. We know that, at very high energies, the electromagnetic and the weak force unify, and are actually a manifestation of the electroweak force, whose symmetry is broken at low energies. Do the other forces — the strong force and maybe even gravity — unify at some even higher energy?
5. And finally, why do the fundamental particles — the ones in the Standard Model — have the masses that they do?

This last one is a problem known as the hierarchy problem in physics, and it goes something like this.

Image credit: © School of Physics UNSW.

There are a few fundamental constants in nature: the gravitational constant (G), Planck’s constant (h or ħ, which is h/2π), and the speed of light (c). There are different combinations of these constants we can create to get values for time, length, and mass; these are known as Planck units.

Image credit: Mass-Energy Scale, via http://universe-review.ca/.

If you were to predict the mass of the particles in the Standard Model from first principles, they ought to be on the order of the Planck mass, which has an energy of around 10²⁸ eV. The major problem is that this mass is 17 orders of magnitude, or a factor of 100,000,000,000,000,000 larger than the heaviest observed particle in the Universe. The Higgs boson, in particular, should have the Planck mass, and — since the Higgs field couples to the other particles, giving them mass — so should all the others.

Image credit: Matthew J. Dolan, Christoph Englert, and Michael Spannowsky, via JHEP 1210 (2012) 112.

So why, we ask, do the particles have the mass that they do, and not much, much larger ones? The best, most elegant solution is that there’s an extra symmetry that cancels out all those Planck-scale contributions, and protects the mass down to a much lower energy.

Image credit: wikimedia commons user VermillionBird.

That’s the idea behind Supersymmetry, known as SUSY for short. Supersymmetry makes the very bold prediction that every one of the Standard Model particles has a partner particle — a superpartner — that has nearly identical properties, except has a spin that’s different by a value of ‎±½ from its Standard Model counterpart.

Image credit: DESY at Hamburg.

This superpartner should protect the mass of all the particles — the Standard Model ones and the SUSY ones — all the way down to the scale at which SUSY is broken, at which point the superpartners acquire a heavier mass than the normal ones.

Image credit: © New Scientist.

If SUSY is broken at the right scale to solve the hierarchy problem, somewhere between 100 GeV and 1 TeV, then the lightest supersymmetric particles should be accessible by the LHC.

But there’s more.

There are a bunch of things that are known not to happen in the Standard Model to very high precision: baryon number isn’t violated, lepton number isn’t violated, and there are no flavor-changing neutral currents. In order to make these things also not happen in SUSY, you need a new symmetry called R-parity, which comes along with an added feature. If R-parity is real and SUSY is real, then the lightest supersymmetric particle is stable, which means, if enough of them are left over from the hot Big Bang, it could be the dark matter!

Image credit: CDMS experiment, Fermilab / Dept. of Energy, via http://www.fnal.gov/.

There’s even one more cool thing that happens: if you take all the particles in the standard model, and you look at the interaction strength of the three forces, you’ll find that the strength of the forces — parametrized by their coupling constants — changes with energy. They change in such as way that, in the Standard Model, they almost meet at some high energy (around 10¹⁵ GeV), but just miss, slightly, if you put them on a log-log scale. But if you add in supersymmetry, the addition of these new particles changes the way the coupling constants evolve. And therefore, if SUSY is right, it could indicate a place where the electromagnetic, weak and strong forces all unify at a high energy!

Image credit: CERN (European Organization for Nuclear Research), 2001. Via http://edu.pyhajoki.fi/.

In other words, there are three major problems that could all be solved by the existence of supersymmetry; it’s a great idea! (There are four if you count the problem of the Coleman-Mandula theorem, which many do, but I’m not one of them.)

But there’s also a few problems with each of these three problems that SUSY looks like it solves:

1. If it solves the hierarchy problem, then there should definitely be new supersymmetric particles discovered at the LHC. In fact, if the LHC doesn’t discover supersymmetric particles, then even if SUSY exists, there must be some other solution to the hierarchy problem, because SUSY alone won’t do it.
2. If the lightest supersymmetric particle is, in fact, the dark matter in the Universe, then experiments designed to see it, such as CDMS and XENON, ought to have seen it by now. In addition, SUSY dark matter should annihilate in a very particular way, which we haven’t seen. The null-detection status of these experiments (among others) is a big red flag against this. Plus, there are plenty of other good dark matter candidates as far as astrophysics is concerned; SUSY is hardly the only horse in the race.
3. The strong force may not unify with the other forces! There’s no reason, other than our predisposition towards liking more symmetric things, for that to be the case. There’s also the issue that if you put any three curves on a log-log scale and zoom out far enough, they will always look like a triangle where the three lines “just barely” miss coming together to a point.

But the biggest failures of SUSY are not theoretical ones; they’re experimental.

Image credit: Geoff Brumfiel from Nature.

And there are a lot of different ways of representing just how difficult it is to reconcile what SUSY expects with what we actually have — and haven’t — seen.

Image credit: Alessandro Strumia, via http://resonaances.blogspot.com/.

At the LHC, supersymmetric particles should have been detected by now, if they exist. There are plenty of theorists and experimentalists who are still optimistic about SUSY, but nearly all models that successfully solve the hierarchy problem have been ruled out.

Image credit: Particle Data Group (2012), O. Buchmueller and P. de Jong.

At this point in the game, based on what we’ve seen (and haven’t seen) so far, it would be shocking if the LHC turned up evidence for supersymmetry. As always, continued experimentation will be the ultimate arbiter of nature, but I think it’s fair to say that the only reason SUSY gets as much positive press as it does is for two simple reasons.

1. A lot of people have invested their entire careers in SUSY, and if it’s not a part of nature, then a lot of what they’ve invested in is nothing more than a blind alley. For example, if there is no SUSY in nature, at any energy scale, then string theory is wrong. Plain and simple.
2. There are no other good solutions to the hierarchy problem that are as satisfying as SUSY. If there’s no SUSY, then we have to admit that we have no idea why the masses of the standard model particles have the value that they do.

Which is to say, SUSY or not, physics still has a lot of explaining to do, and there’s work to be done. But the biggest problem is that SUSY predicts new particles, and it predicts their existence to occur in a fairly specific range of energies.

Image credit: Matt Strassler of http://profmattstrassler.com/.

If they’re not there, then this isn’t the right story. At this point, the theoretical hoops being jumped through to keep SUSY “viable” (and yes, that belongs in air quotes) given our experimental null results are getting progressively more and more extravagant. I’m not much of a betting man, but if I were, I’d say that SUSY is already dead. It’s just waiting for the coffin nails to be hammered in.

“How is it they live for eons in such harmony - the billions of stars - when most men can barely go a minute without declaring war in their mind against someone they know?” -Thomas Aquinas

Welcome back to another Messier Monday here on Starts With a Bang! Each Monday, we take an in-depth look at one of the 110 deep-sky wonders — all visible with a small telescope or even good binoculars — that make up Charles Messier’s original catalogue of non-cometary objects! Today, we’re taking a look at a one-of-a-kind galaxy among the Messier objects, which just happens to be the (co-)first galaxy I ever found-and-saw for myself!

Image credit: Alistair Symon, 2005-2009.

The object for this week is The Cigar Galaxy, Messier 82. And the reason it’s the first object I’ve ever found is because its location is so easy that even if the only thing you can find in the night sky is the Big Dipper, this galaxy will be unmistakeable when you see it through your telescope/binoculars. To get started, simply locate the “cup” of the Big Dipper.

Image credit: me, using the free software Stellarium, via http://stellarium.org/.

In particular, you’ll want to find stars that mark the “tip” of the cup, Dubhe, and the opposite “base” of the cup, Phad. Draw an imaginary line from Phad-to-Dubhe, and then extend that line the same distance again, so that you wind up near the faint naked-eye star d Ursae Majoris. If you then point your binoculars or low-power telescope at that location, a pair of galaxies — the first external galaxies I ever found in the night sky for myself — will be yours to behold.

Image credit: me, using the free software Stellarium.

They’ll very likely look like very faint clouds, but unlike actual clouds they’ll never move relative to the rest of the sky or change shape. That’s because these two objects are galaxies, the previously-looked-at Messier 81 and the smaller, cigar-shaped Messier 82! It was discovered in 1774 by Johann Elert Bode, one of Messier’s contemporaries, and looks rather unspectacular next to the great spiral that is Messier 81.

Image credit: © 2006 – 2012 by Siegfried Kohlert of http://www.astroimages.de/.

But despite being one of the smallest galaxies in the Messier catalogue, M82 holds a unique distinction: it’s the only starburst galaxy out of the 40 Messier galaxies! We have plenty of star-forming regions in our own galaxy, where neutral (mostly hydrogen) gas is collapsing to form new stars, and a great deal of hydrogen gas becomes ionized, giving off a characteristic pink glow thanks to the electrons.

Well, in rare cases in astronomy, the majority of the entire galaxy becomes a star-forming region, and that’s what we call a starburst galaxy!

Image credit: Pablo Rodríguez-Gil (IAC) y Pablo Bonet (IAC), with the William Herschel Telescope.

So, meet Messier 82, at just 12 million light-years distant, the closest starburst galaxy in the Universe! Of course, this galaxy wasn’t always forming stars at this insanely fast rate; something had to happen to trigger it. And — in this Universe at least — there’s only one thing we know of that triggers star formation rates this high: either a gravitational interaction or a collision with another massive object.

In the case of the Cigar Galaxy, the culprit is easy to see.

Image credit: Emil Ivanov of http://www.emilivanov.com/.

It’s Messier 81! These two galaxies were once simple, undisturbed spiral galaxies, much like Andromeda and the Triangulum Galaxy are in our own backyard. But the gravitational interactions between these two neighbors — as they enter the process of merging with one another — causes tidal tails and extended arms in the larger, more massive M81, and has triggered a starburst in the smaller, more disrupted M82. The star formation rate in the Cigar Galaxy is presently about 10 times higher over the past 100 million years than it should otherwise have been.

Image credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA).

Thanks to the Hubble Space Telescope, we’ve learned that there are actually 197 distinct star-forming regions in-and-around the center of Messier 82, with each one containing the mass of about 200,000 Suns! This incredible star-formation rate, as the merger process continues, will eventually increase even further over time! If you want proof that the entire galaxy has heated up, all you have to do is take a peek in the infrared.

Image credit: NASA / JPL-Caltech / UCLA.

As you can see, Messier 81 and 82 look very different than they do in the visible! The blue light represents stars, while the green and red shows off warm dust. As the WISE image above definitively shows, the Cigar Galaxy is filled with warm gas-and-dust!

With all these new stars being formed, you might expect that M82 is a hotbed of supernovae. Although the light-blocking dust is very heavy in the visible part of the spectrum, we can (and do) look in the radio to see what’s going on as far as supernovae are concerned.

Images credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA); A. Brunthaler, MPIfR.

In fact, the Cigar Galaxy has (probably) had three of them in just the last decade! Its spiral arms were only discovered in the last decade as well, as the near edge-on orientation (it’s tilted at 80° relative to us) made it incredibly difficult to decipher. Because of the starburst going on, it’s still classified as an irregular galaxy, and it’s only going to get worse from here, as the merger process — probably originally begun about 600 million years ago — continues.

Compare what the infrared (via Spitzer) reveals, when compared to a “visible-only” image.

Images credit: NASA / JPL-Caltech / University of Arizona and NOAO.

We can also learn some amazing stuff about this galaxy using the highest-energy light it emits: X-rays! Point X-ray sources — evidence of black holes and neutron stars — litter the inner region of the galaxy, with the strongest source coming from the center, where there’s a black hole estimated to weigh in at 30 million Suns, some 10 times as massive as the Milky Way’s central black hole!

Image credit: NASA / Chandra X-Ray Observatory.

So what else is there to showcase? How about a grand composite image of Hubble, Spitzer and Chandra, all together?

Image credit: NASA/JPL-Caltech/STScI/CXC/UofA/ESA/AURA/JHU.

While it may be a small, faint fuzzy cloud through your telescope, make no mistake: a fantastic part of cosmic history — the assembly, buildup and mergers of galaxies — is present right in our own backyard, and you get a glimpse of it every time you look just outside the Big Dipper at the Cigar Galaxy: M82!

Including today’s entry, we’ve covered the following Messier Objects:

• M1, The Crab Nebula: October 22, 2012
• M8, The Lagoon Nebula: November 5, 2012
• M13, The Great Globular Cluster in Hercules: December 31, 2012
• M15, An Ancient Globular Cluster: November 12, 2012
• M20, The Youngest Star-Forming Region, The Trifid Nebula: May 6, 2013
• M25, A Dusty Open Cluster for Everyone: April 8, 2013
• M30, A Straggling Globular Cluster: November 26, 2012
• M33, The Triangulum Galaxy: February 25, 2013
• M37, A Rich Open Star Cluster: December 3, 2012
• M38, A Real-Life Pi-in-the-Sky Cluster: April 29, 2013
• M40, Messier’s Greatest Mistake: April 1, 2013
• M41, The Dog Star’s Secret Neighbor: January 7, 2013
• M44, The Beehive Cluster / Praesepe: December 24, 2012
• M45, The Pleiades: October 29, 2012
• M48, A Lost-and-Found Star Cluster: February 11, 2013
• M51, The Whirlpool Galaxy: April 15th, 2013
• M52, A Star Cluster on the Bubble: March 4, 2013
• M53, The Most Northern Galactic Globular: February 18, 2013
• M60, The Gateway Galaxy to Virgo: February 4, 2013
• M65, The First Messier Supernova of 2013: March 25, 2013
• M67, Messier’s Oldest Open Cluster: January 14, 2013
• M72, A Diffuse, Distant Globular at the End-of-the-Marathon: March 18, 2013
• M74, The Phantom Galaxy at the Beginning-of-the-Marathon: March 11, 2013
• M78, A Reflection Nebula: December 10, 2012
• M81, Bode’s Galaxy: November 19, 2012
• M82, The Cigar Galaxy: May 13, 2013
• M83, The Southern Pinwheel Galaxy, January 21, 2013
• M92, The Second Greatest Globular in Hercules, April 22, 2013
• M97, The Owl Nebula, January 28, 2013
• M102, A Great Galactic Controversy: December 17, 2012

Come back next week, where we’ll take a look at yet another one of the 110 deep-sky objects that make up the Messier catalogue; don’t miss it!

“But I’ll tell you what hermits realize. If you go off into a far, far forest and get very quiet, you’ll come to understand that you’re connected with everything.” -Alan Watts

As we move farther away from the equinox and towards the solstice, my part of the world is seeing not only more daylight, but also more sunshine, warmer temperatures, and — at least today — some glorious days to be out in nature. This weekend, have a listen to Vishwa Mohan Bhatt, Ronu Majumdar, Sabir Khan & Tarun Bhattacharya‘s interpretive nature song,

Flame of the Forest,

while I share with you my list of the top 10 forests in the world that I’d most like to see! (So, yes, this automatically excludes some of the magnificent forests I’ve already had the pleasure to be in, including the one on the mountainside of Mt. Fuji, atop!) In no particular order, here they are (and as always, click on them for the best-resolution image available):

Image credit: High Definition Wallpapers, via http://www.artswallpapers.com/.

10.) The Amazon Rainforest, South America. The largest rainforest in the world, it dwarfs all other rainforests on Earth combined. There’s arguably a greater diversity of flora and fauna found here than anywhere else on the planet. There’s no way a simple picture can do this — or any of the forests listed here — true justice, but I’d love to experience it for myself.

Image credit: Mariusz Jurgielewicz.

9.) Sequoia National Forest, California. An entire forest named for the largest trees in the world, the sequoias. Above is an image of General Sherman, the tree with the single largest mass-and-volume in the world. It’s older than the Roman Empire, nearly as tall as the Statue of Liberty, wider than all trees except the baobabs, and in 2006 lost a branch that was bigger than most full-grown trees! If you took just the trunk and dehydrated all the water out of it, it would still weigh over 1,000 tonnes. And yes, there’s a whole forest full of trees just like it.

Image credit: © William Manning / Corbis.

8.) Redwood National Park, California. Home to the tallest trees in the world, I’ve actually seen a number of Redwoods along the California and Oregon coasts, although I’ve never been to the eponymous national (or state) park. A forest of trees stretching upwards so high that you can’t even see the treetops on a foggy day, this is too close for me to not see it, and soon. I really have no excuse.

On the other hand, there are plenty of forests I want to see that would require a little more legwork.

Image credit: imgur user StaphInfection, via http://imgur.com/gallery/QMJgq.

7.) The Crooked Forest, Poland. The youngest forest on my list, the Crooked Forest was planted around 1930, and consists of around 400 oddly-curved trees like this. Appearing to be normal pine trees in an otherwise unremarkable forest, it’s thought that they’re curved like this due to some hitherto undiscovered human intervention. So unique, it reminds me of Pearl Fryer, and I’d love to get the chance to experience it for myself.

Image credit: Wikimedia commons user Prasanaik.

6.) Jog Falls environs, India. While most of India’s primeval forest has changed dramatically thanks to human intervention, North Sentinel Island is not exactly on the list of places where I think I’d be welcomed. Jog Falls, on the other hand, is the largest waterfall in India, shown here during monsoon season, at its most spectacular! The entire western region of India is home to some of the greatest biodiversity in the world, and I’d love the chance to walk through the forested areas here.

Image credit: flickr user Fordan, a.k.a. Bob Snyder.

5.) Daintree Rainforest, Australia. The oldest surviving rainforest in the world, Daintree is among the most biodiverse regions in the world as far as plants, marsupials, insects and spiders are concerned. How could you not be intrigued?

Image credit: Andy Linden (flickr user andylinden).

4.) Black Forest, Germany. Called “black” by the Romans because of how the dense conifers so successfully block out the Sun, even during the daytime, the black forest is dotted with lakes that formed from the melt at the end of the last ice age. The black forest contains eight of the highest mountains in Europe mountain peaks over 1,000 meters in elevation (thank you, Lassi @2), and is home to unique animals found nowhere else, such as the giant earthworm. Pretty cool!

Image credit: Copyright 2002 – 2011 BrotherSoft.com.

3.) Jiuzhaigou Valley, Sichuan, China. I mean, just look at that picture, will you? Both an UNESCO world heritage site and a world biosphere reserve, this valley on the edge of the Tibetan Plateau is full of colorful lakes, multiple waterfalls, snow-capped peaks, and of course, beautiful primeval forests. 30 years ago, only 5,000 tourists visited this region each year; now that number is well in excess of a million. And even though I know that increased human traffic means that keeping the site pristine takes more and more effort, I still want to see this for myself.

Image credit: Martin Hertel, National Geographic’s “Your Shot”.

2.) Beech Forest, Germany. Not so much a single “place” as it is a collection of forest sites across many different nations, this is another UNESCO world heritage site. Dominated by Beech trees, they form an impressive canopy even in the winter, as this photo by Martin Hertel elegantly shows.

And finally…

Image credit, Yuya Horikawa of http://500px.com/photo/9349539.

1.) Sagano Bamboo Forest, Japan. I’ve never seen a forest like this before, and I didn’t learn about it until years after I was in Japan. How was I to know that I was only a few miles (kilometers) away from this wonder when I spent time in Kyoto? The entire district of Arashiyama looks beautiful, but the great bamboo forest is surely the great highlight!

And that’s a wonderful collection of my top 10 forests that I’d love to visit, someday. Hope you enjoyed it, and feel free to comment on these choices, as well as to share any others that have connected with you!

“As seismologists gained more experience from earthquake records, it became obvious that the problem could not be reduced to a single peak acceleration. In fact, a full frequency of vibrations occurs.” -Charles Francis Richter

You’ve all been around long enough to be familiar with the severe damage that earthquakes can cause, rattling and cracking the ground, shaking down buildings, and creating catastrophic tsunamis tidal waves. In short, the largest ones that occur in the wrong places will cause billions of dollars worth of damage and will kill thousands of people.

Image credit: AP / Press Association Images.

As you may well imagine, the Earth is hardly the only world that is geologically active like this, spontaneously and naturally quaking. Other planets like Venus have quakes, the Moon has them, even stars like the Sun have quakes!

Movie credit: Charlie Lindsey and Alina Donea of RHESSI Science Nuggets.

Of course, all of these quakes release large amounts of energy; the quakes on the surface of the Sun release somewhere in excess of 40,000 times the energy of the 1906 San Francisco quake, one of the most destructive in recorded history! But what you might not realize is that all of that energy has to come from somewhere, and the naïve explanation — tectonic plates colliding — simply won’t do.

Image credit: Earthquake Information Bulletin, v. 9, no. 6, Nov./Dec. 1977, Henry Spall, USGS.

Plate tectonics tells you where earthquakes are most likely to occur, and the geophysics of the Earth’s crust tells you the different types of faults that cause these quakes, but neither of these tells you where the energy for these quakes comes from.

There’s a hint, though, if you’ve ever tried spinning with your arms out, and then brought them in.

Image credit: Pearson education / Addison-Wesley.

There are only a few quantities in this physical Universe that are fundamentally conserved, and one of them happens to be angular momentum. Angular momentum, in plain English, is the product of your rate of rotation (known as your angular velocity) and how your mass is distributed (known as moment of inertia). When you bring your arms in, your moment of inertia goes down, and hence — in order to conserve angular momentum — your rate of rotation needs to go up!

Well, guess what we notice about the Earth after each-and-every measurable earthquake?

Image credit: Wikimedia Commons user Wikiscient.

By just the smallest of amounts, the rotational period of a day shortens. For example, the 2011 Japan earthquake (including aftershocks) shortened the day by 1.8 microseconds, the 2010 Chile earthquake shortened the day by 1.26 microseconds, and the 2004 Sumatra quake shortened the day by an astounding 6.8 microseconds!

These are tiny numbers, of course, considering that we lose about 14 microseconds from the 24-hour-day each year just due to tidal friction from the Moon-Earth-Sun system, but it’s measurable nonetheless. And since angular momentum is conserved and the Earth’s angular velocity changes, that tells us that with each earthquake, the Earth’s moment of inertia must change, too.

Image credit: Jean Anastasia.

But unlike you when you bring your arms in, the Earth has no external source of energy to cause this change-in-configuration. There’s only one place for this energy to come from: gravitational potential energy!

The Earth, as you well know, is (naturally) made up of all the stable and quasi-stable elements in the periodic table, which includes all the elements from 1 (hydrogen) to 94 (plutonium), exempting the three unstable elements along the way.

Image credit: Michael Dayah, of http://ptable.com/.

You can imagine an Earth quite unlike the one we enjoy today: one that was perfectly segregated by element in concentric layers, like some kind of atomic onion. On average, the most massive stars in the Universe do a remarkable approximation of this, and so you can imagine arranging the Earth in a perfect onion, with a tiny core of plutonium, enveloped by a thick spherical shell of uranium, in turn enveloped by protactinium, thorium, and so on.

Like I said, ultra-massive stars do something very close to this, and to some extent, so does Earth, already.

Image credit: http://cde.nwc.edu/ (L) and McGraw-Hill (R).

But we’re not perfectly layered; it’s not even close. Each big earthquake that causes an ~1 microsecond speed-up in the Earth’s rotational day is the equivalent of moving some ten billion tons of uranium from the Earth’s surface all the way to the center of the inner core! Of course, real earthquakes involve a much slighter rearrangement of much larger amounts of material: usually quintillions of tons of mass moving by just centimeters.

Still, each time we have an earthquake, that’s one tiny step closer to our ideal density configuration!

Image credit: USGS.

So where does an earthquake’s energy come from?

From the gravitational potential energy stored in the elemental configuration of the Earth itself! And when an earthquake occurs, that’s the Earth slightly rearranging its mass to lower its moment of inertia, increase its angular velocity, and to turn that gravitational potential energy into some very frightening and destructive kinetic energy!

Image credit: the 2009 Haiti earthquake, via http://peaceandloveinternational.com/.

As the Earth continues to cool, shrink, and radiate its heat away, more rearrangements like this are inevitable.

For the intricacies of earthquakes and the Earth’s interior, you need to understand an awful lot about geology and geophysics, but for the basic physics of earthquakes, and where they get their energy from? It’s as simple as rearranging atoms, and bringing the heavier elements closer to the core!