Ever since I was a child I have had this instinctive urge for expansion and growth. To me, the function and duty of a quality human being is the sincere and honest development of one's potential. -Bruce Lee
It isn't only our heros that expand and grow; the Universe does that, too! In the first three parts of our series, we talked about inflation, its end, and the hot big bang. But during all of this time, the Universe has been expanding.
This is probably the most confusing aspect of cosmology, so tread slowly through this. First off, it is space itself that is expanding. It doesn't make sense to ask "what's it expanding into?" Because space is like the surface of an infinitely stretchy balloon: it can get bigger or smaller, but it doesn't require anything external to itself.
Now, one of the biggest thing that we learn from General Relativity when we apply it to cosmology is how space expands, and what happens to the Universe as a result. In fact, it turns out that the only thing that governs the expansion of a flat Universe (like ours) is the Universe's energy density, and that's it.
Well, during inflation, the energy density of the Universe is a constant, which means the expansion rate (which is fast) is also constant. This means the Universe expands exponentially, like so.
The way this works is that after a short amount of time (for inflation, the time is something like 10-20 or 10-30 seconds), the size of the Universe doubles. After another one of those "doubling times", the Universe is double that new size, or 4 times the original size. If you can go for 100 doubling times (10-18 or 10-28 seconds in our two examples), the Universe will now be 2100 times its original size. It is in this fashion that we can get an arbitrarily large Universe in a fraction of a second, and that's what inflation gives us.
Come now to the end of inflation, where the entire Universe may be the size of your thumb, or it may be a bajillion (roughly) times the size of our Universe right now. The actual, physical size of our Universe at that time doesn't really matter. Why not? Because the part of it that becomes the entire observable Universe -- about 100 billion light-years across today -- was only about the size of your thumb at the moment the big bang began.
But when inflation ends and (what I call) the Big Bang began, everything changes. The expansion rate was still the same, and the energy density is still incredibly large, but now the Universe's energy is in the form of matter and radiation. When the Universe continues expanding now, the energy density drops, because you've got the same amount of stuff, but the volume it occupies increases! This means the energy density goes down, and hence, so does the expansion rate!
So the Universe inflates, and the expansion is very fast and constant. When inflation ends, matter and radiation fills a small region of this space (the region that becomes our observable Universe), and the expansion -- although still very fast -- is now slowing down. The Universe is therefore cooling as it's expanding, and despite being filled with all the possible fundamental particles that can exist at these incredible energies, will not stay that way for long.
The first thing the Universe needs to do? Figure out a way to create more matter than anti-matter, because at the very beginning, there's about a billion times more of both matter and antimatter than there is of either one today. That's the next chapter in our story, so come back for it!
Here in the United States, it's Super Bowl Sunday, and the Colts play the Saints for the championship of our National Football League. We listen to music that pumps us up,
and -- of course -- we watch the big game. And I'm here to see what our Starts With A Bang readership thinks -- both nationally and internationally -- about who's going to win. Then I'm going to give you my pick. (Feel free to leave your own opinions in the comments!)
Colts and Saints: two teams that looked like juggernauts early on (the Saints started out the season 13-0 and the Colts, 14-0) with two of the best quarterbacks in the league, Drew Brees and Peyton Manning. Who's going to win?
The Colts. And why? Their offensive line. The Colts' defense is pretty good, but Drew Brees and the Saints' offense will definitely put points on the board. But not on every drive. The Saints' defense -- unlike their last game against the Vikings -- will not be able to pressure and pound Peyton Manning like they did to Brett Favre. And if you can't get to Manning (and you have to be suspicious of the Saints' defense), he's going to score at will on you. Especially when it gets close to crunch time.
And that's what I expect to happen: for the Colts to pull away from the Saints in the second half, and for the Saints' defense to be unable to do anything about it.
And finally, if you don't care for my picks, why not try Carl Brutananadilewski's from Aqua Teen Hunger Force?
What we know about Pluto today could fit on the back of a postage stamp. -Colleen Hartman
Part of the joy of astronomy is, every once in a while, you just get an astoundingly beautiful new picture or video of a foreign planet, star, galaxy or cluster. Pluto, the most distant planet, is among the most elusive.
This picture above was snapped by the Hubble Space Telescope about a decade ago, and shows us Pluto (center) with its large moon Charon and its two smaller moons, Nix and Hydra.
It's pretty difficult to get better resolution pictures of that planet because Pluto is both so far away and so tiny. There was an attempt to image surface details on Pluto back in 1996 using Hubble, and the results were only marginal.
I'm always disappointed when I have to show an artist's rendition, though, so I was reluctant to even try. I just found out today that new pictures were released, and so I was licking my lips in anticipation.
What's awesome about this? They weren't just able to image Pluto's surface, they were able to image the surface as the planet rotated, which means we can see what the surface of the planet looks like everywhere! Check it out, and click to enlarge!
But the most spectacular thing I've been able to find about this? A high-resolution video of Pluto rotating, made from a whole slew of images stitched together digitally. Want to see what Pluto looks like as it spins? Just watch.
Want to watch the super hi-res version? Click here. Yes, Pluto, you're not a planet anymore, but don't think for a minute that we all aren't still awed by you. I have no idea what that giant frozen-looking feature is, but I'm sure there will be scientific papers out on it in the near future! Thanks for sharing just a bit of your secrets!
Nobody can go back and start a new beginning, but anyone can start today and make a new ending. -Maria Robinson
In parts one and two, we covered the very beginning of the Universe as we know it. Specifically, we talked about inflation, which is the process that sets up the Big Bang. Inflation -- to recap -- expands the Universe exponentially fast, driving the matter density to zero and stretching the Universe flat like a balloon getting blown up supremely fast.
But inflation ends, and when it does, all of that stored (i.e., potential) energy that was being used to expand the Universe now gets converted into matter and energy.
This moment -- when the Universe fills with energetic stuff -- is the beginning of the hot Big Bang, and the Universe as we recognize it.
Well, almost as we recognize it. At this moment, the Universe has an incredibly hot temperature. Typically, we measure temperatures in Kelvins. Liquid nitrogen boils at 77 Kelvin, room temperature is about 300 Kelvin, and the surface of the Sun is about 5700 Kelvin. By comparison, at the beginning of the Big Bang, the temperature is at least 1015 Kelvin and up to (but not more than) 1029 Kelvin!
For comparison, the hottest part during the hottest time of a Supernova (the hottest explosion in the Universe) is only about 1011 Kelvin, or at least 10,000 times cooler than the Big Bang.
So what does our Universe look like? Imagine taking all of the matter (all 1080 atoms or so) in the Universe, all of the photons (about 1090, more or less), all of the neutrinos (about another 1090), and smashing them into a volume the size of your thumbnail.
That's right, the Big Bang is a time back when the Universe was squished into a region that made it about 1070 times denser than you are right now. Or rather, the most conservative estimate of the Big Bang involves that. If you want to go to the other extreme, the most fantastic estimate is that all of that matter and energy is concentrated into a volume the size of a single proton.
Only, instead of three quarks in there, there would be something like 1090 of them.
Want to know what's even crazier? There is just as much antimatter as there is matter right after the big bang! For every electron flying around, there's an anti-electron flying around; for every quark there's an anti-quark, and for every subatomic particle you can dream up, there's it's anti-particle in equal abundance.
And do you know how much of it there was? About a billion times more matter and antimatter than exists (combined) of both of them today.
A lot of people like to start the clock on the Universe imagining that it started as a singularity. As we've discussed before, there's absolutely no reason to think this must be true. But if you insisted anyway and defined that time as t=0, the conservative (lowest energy) estimate for when this Big Bang occurs would be when the Universe is 10-10 seconds old, and the fantastic (highest energy) estimate would be when the Universe is 10-38 seconds old.
And that's the beginning of our Universe: tiny, young, hot, and full of everything. The whole point of telling this story -- what I call the greatest story ever told -- is to understand how we got from this point, the very beginning, to where we are today.
So enjoy this step that takes us into what most of us call "our Universe", and come back later for part four, where we'll talk about how to get rid of all that pesky antimatter and leave us with the right amount of matter for you and me!
I'm as mad as hell, and I'm not going to take this anymore! -Howard Beale
Let me tell you a little story. Nine years ago, I was living in California, and I had a car accident. The damage to my car was pretty bad; the first estimate I got said that it would take about $3800 to fix it, more than the entire value of my (then) 11-year-old Volkswagen, and about one-and-a-half months' salary for me at the time.
What I decided to do was -- I hope -- what any reasonable person would do. I had just enough repair work done so that the car was drivable, and then I took it around to different shops. Why? I wanted to get the best quality work done for the price I was paying, and I knew that some places would wind up charging more. I wound up choosing Chan's Body Shop (which apparently still exists!), and saved myself over $1000 (including the original 'get-it-drivable' work) from the original estimate.
Now, let me pose the following hypothetical question to you: what do you think I should have done if Chan's body shop made me pay them up front, and then when they had spent all of my money, told me that they needed an extra $1500 to finish fixing my car?
You'd better believe I'd do something about it! At best, it's dishonest and incompetent business. At worst, it's fraud and extortion. Either way, I wouldn't stand for that sort of behavior in my own life.
So why do you accept it from your space agency? Applying for NASA funding is extremely competitive, with contracts usually going to the organization that promises the most science in the right area for the cheapest amount of money. Yet, unlike in the real world, these projects are never completed within their budgets. Mars Science Laboratory is over half a billion over budget already, the budget for Hubble's successor, the James Webb Space Telescope, has ballooned to over 5 billion dollars, and the proposed "flagship" for manned spaceflight, the new Ares-I rockets, has cost NASA over 9 billion dollars, will take a total of about $100 billion until it's completed to design specifications, and has very little to offer.
So, to many people's chagrin and to my delight, Obama has cancelled the Ares I project. From the BBC article:
in his federal budget request issued on Monday, Mr Obama said the project was "over budget, behind schedule, and lacking in innovation".
It was draining resources from other US space agency activities, he added.
He plans instead to turn to the private sector for launch services.
Why am I so happy about this? Because the project is over budget, it is behind schedule, and it is hugely expensive and lacking in innovation.
But my hope is that this will do more. My hope is that it will force those applying to NASA for funding to be honest and competent in their budget proposals. If you wouldn't accept this kind of behavior from your auto mechanic then why would you accept it from your space agency and those whom it employs?
"Oh, you paid me to do this job and I took all your money but I didn't finish the job. Can I have another couple billion dollars a year for the next decade while I figure it out?"
Umm... no. And I hope that this sets a precedent that nobody else can do this, either. It's one of the worst forms of incompetence out there, and the fact that this behavior has been treated as acceptable by NASA administrators for so long has really restrained the ability of NASA to meet its mission statement:
So why am I optimistic? Because the commercial sector has the potential to get people excited about space in a way that NASA has failed to do. Want to go to space? Commercial ventures will get you there someday soon.
Last week, I also wrote about how the Constellation program was doomed because it offered no ambitious, awe-inspiring goals. Well, here's an awe-inspiring goal. Ever heard of Edmund Hillary and Tenzing Norgay? They were the first humans to summit Mount Everest.
What could be more ambitious than that? Climbing the highest mountain in the Solar System, Mars' Olympus Mons.
There's already a mountaineering contest, complete with awards, set up for anyone who wants to accomplish this. Could this happen within my lifetime?
Could someone set the deep-sea-diving record for depth by drilling through the ice on Europa? There's no prize set up for this, but would there be possible commercial interest?
Already, I find myself more inspired than spending $100 billion to redo something we already did more than 40 years ago. We are explorers who push the frontiers of what we can accomplish as a species. Let's push forward together instead of trying to relive the past, and let's make sure we tell everyone at NASA that they need to be honest, realistic and competent with their proposals. No excuses; just do better from now on. And while many other will lament the passing of Constellation, I'm optimistic that this is the step in the right direction for NASA. Let's hope they make the most of it.
Science Channel Refuses To Dumb Down Science Any Further
SILVER SPRING, MD--Frustrated by continued demands from viewers for more awesome and extreme programming, Science Channel president Clark Bunting told reporters Tuesday that his cable network was "completely incapable" of watering down science any further than it already had.
"Look, we've tried, we really have, but it's simply not possible to set the bar any lower," said a visibly exhausted Bunting, adding that he "could not in good conscience" make science any more mindless or insultingly juvenile. "We already have a show called Really Big Things, which is just ridiculous if you think about it, and one called Heavy Metal Taskforce, which I guess deals with science on some distant level, though I don't know what it is. Plus, there's Punkin Chunkin."
"Punkin Chunkin, for Christ's sake," added Bunting, referring to the popular program in which contestants launch oversized pumpkins into the air using catapults. "What more do you people want?"
Along with Bunting's remarks, the Science Channel issued a statement claiming that it currently airs more than 150 programming hours that are tangentially, and often laughably, related to science, and that staff members are unable to bring themselves to make those hours even more asinine.
Debbie Myers, general manager of the Science Channel, said the cable station has maintained a balance of 5 percent science content and 95 percent mind-numbing drivel over the past few years, and that this was as far as they were willing to go.
"At this point, having the word 'how' in a show's title is about as close to scientific investigation as we get," Myers said. "In fact, I don't even know how we can justify airing a show like Mantracker at all. A cowboy hunts contestants down using his trailing skills? I guess you could say it makes the audience use 'observation' by watching what happens on screen."
"Observation is a part of science, right?" Myers added. "Jesus Christ."
A survey of the network's current schedule confirmed Monday that on-air demonstrations of such basic scientific principles as "inertia" and "momentum" are mostly relegated to pushing a blindfolded participant strapped to an office chair down a steep hill, while other concepts, such as "sublimation," are regularly demonstrated by strapping dynamite to a large fiberglass Big Boy statue and then watching it explode.
As evidence of their refusal to further water down programming, network sources pointed to a number of proposed shows they've abandoned in recent weeks, including an animal-based bungee-jumping program called Extreme Gravity, and Atom Smashers, a series that was was roundly rejected by focus groups as being "too technical" and "not awesome enough."
"People liked that the particle accelerators were really huge, but apparently the show didn't have enough smashing to hold their interest," said a former employee who wished to remain anonymous. "In the end, it was either add a huge monster truck for no reason whatsoever or pull the plug on the entire project. Honestly, I don't think I'd be able to face my wife and children had we gone through with it."
While they won't be dumbing down their already crude lineup of shows, Science Channel officials assured viewers that the network will continue to cater to the lowest common denominator and will keep airing embarrassingly base content completely stripped of all intellectual integrity. Officials also noted that the cable channel greatly values the 18- to 45-year-old demographic of louts, clods, and empty-headed dumb fucks.
"I don't like it when the science people talk about things no one can even understand," said Rich Parker, an Ohio resident. "It's like, just quit your yapping and dip the chain saw into the liquid nitrogen already."
David Zaslav, CEO of the network's parent company, Discovery Communications, said he has not ruled out rebranding the Science Channel as the Stuff Channel.
We shall not cease from exploration and the end of all our exploring will be to arrive where we started... and know the place for the first time. -T.S. Eliot
Yesterday, President Obama delivered his first State of the Union Address, and talked about a number of things that ranged from inspiring to disappointing. But one thing that didn't make it into the address was the rumor that NASA's Constellation program (including the AresRocket designed to launch crews) will lose their government funding.
(Please note: what follows is my opinion, and I take responsibility for it.) If this actually happens, I think this is one of the best things that could happen to NASA. When the Apollo program was at its height in the late 1960s, we had a grand vision of where we were headed. Walking on the Moon was going to just be the first step; our goals for the future were going to include permanent outposts in low-Earth Orbit, on the Moon, and eventually the exploration and colonization of other worlds. It was no stretch of the imagination to believe that, 30 years in the future, we would routinely have people who lived in space aboard stations with their own artificial gravity, like in 2001: A Space Odyssey.
And doesn't that seem like a pipe dream today? After the end of the Apollo program in 1975, the only manned space mission run by NASA has been the Space Shuttle program, which cannot reach beyond low-Earth orbit. Although it has been marginally scientifically useful, there simply isn't the awe that was present in traveling to the Moon. Moreover, the largest, most successful "space station" that we have is the ISS, which looks anything but impressive when compared to 1968's science fiction.
Moreover, the ISS is fairly useless scientifically. So in 2004, when then-President Bush announced a new space initiative for manned spaceflight, I was at first optimistic, and then almost immediately devastated. Why was this so disappointing to me? Let's go over some reasons.
There are no awe-inspiring short term goals.
The vision's major mandate -- establishing an extended human presence on the Moon -- has no clear scientific merits.
It is already way over-budget and behind schedule, delivering lackluster results to this point.
The vehicles presently in development are insufficient to take us beyond the Moon anyway.
The long-term goal -- to send a team to Mars -- is unreachable by even the most optimistic estimates until the 2030s.
It affirms the perception that the space program is a waste of tax dollars.
It is appalling to me that this vision is still in place as current policy. The Ares rockets currently in development (Ares I and Ares V) are barely improvements in any way over the Saturn V rockets from nearly half a century ago, even on paper!
What was even worse? When this vision was instituted, it basically cost NASA $1-$2 billion per year to fund it. But NASA's funding was not increased to cover that cost, causing them to scrap about 5-10% of their total budget to make room for this new initiative.
While there are many opinions out there on this, I am unequivocally in support of Obama's pulling the plug on this monstrosity of a funding-eater. NASA has already spent about 8 billion dollars on the Ares rockets and other Constellation-related programs, and -- in order to get humans back to the Moon by 2020 -- will need to spend around 100 billion total. Keep in mind that NASA's entire budget for this fiscal year is just over 18 billion dollars, so if NASA is no longer bound to do this, they will be free to fund missions that are actually scientifically valuable.
But my great hope is that they'll actually use these freed-up funds to reach for something truly awe-inspiring. Landing humans on other planets, searching for (and possibly finding) life elsewhere in the Solar System, or perhaps even reaching for another star system... there are plenty of goals out there that we can shoot for that people will be excited for.
I'm simply reminded of the great artist Michaelangelo, and my favorite thing that he ever said,
The greater danger for most of us lies not in setting our aim too high and falling short; but in setting our aim too low, and achieving our mark.
So aim high, and encourage your local space agency to reach for the greatest heights that are out there.
Blue flower, red thorns! Blue flower, red thorns! Blue flower, red thorns! Oh, this would be so much easier if I wasn't color-blind! -Donkey, from Shrek
Earlier this week, I introduced you to the Red Controversy, the observations recorded around 2000 years ago in Europe asserting that the star, Sirius, appeared red.
Now, taking a look at Sirius today, it is clearly not red:
And, based on what we know about stars, they don't change color on timescales that quickly. Many of you put forth some very good ideas, and I thank you for the comments. In fact, the most common one was the very first idea considered by scientists who took this seriously: when anything is low on the horizon, it appears red. Case in point: the Moon.
Would this be reasonable? The answer is, unfortunately, no. Why not? We see references to lots of other bright stars that reach similar positions above the horizon in the sky as Sirius does, and their colors are reported accurately. Also, the reddening effect of objects close to the horizon was well-known, and it's hard to believe that someone as astronomically knowledgeable as Ptolemy would fall for this. Moreover, Ptolemy lived in Egypt, where Sirius gets awfully far above the horizon and doesn't appear red at all during many times of the year.
Many of you also pointed out that particles in the atmosphere, such as intense volcanic eruptions, can change the apparent colors of astronomical objects. (In fact, we've talked about that recently.) But they wouldn't do it for hundreds of years; Horace, writing in Europe in the 1st Century BC, would not see the same thing as Ptolemy, writing in Africa in the 2nd Century AD. Although, this was a reasonable line of thought, especially considering that there is some evidence from China that they saw Sirius as white during this same time.
(As an aside, the argument that a later source stuck that sentence about Sirius being red in Ptolemy's work after reading Horace or Aratus (both poets) and deciding that Sirius belonged in that list of red stars as well is possible. However that assertion is impossible to confirm or refute, so it isn't talked about among scientists.)
So, what could have caused Sirius to appear red in the past, and are any explanations still feasible? There are three major schools of thought.
1.) Bok Globules. These relatively dense clouds of interstellar gas and dust move through our galaxy, blocking out starlight and definitively reddening the brightest stars behind them. This is an intriguing suggestion, because one could not only pass in front of a star, making it appear red, but it could move quickly enough that it could transit in just a few hundred years.
But the argument falls apart on one count: Sirius incredible brightness. Sirius is the brightest star in the sky, and it was reported as the brightest 2000 years ago as well. If you want a Bok Globule to be significant enough to redden it, it would dim Sirius enough so that, at best, it would be around the 15th brightest star in the sky. We also don't find any Bok Globules in that area of the sky, which hurts that argument significantly. Therefore this idea, although intriguing, is widely rejected.
2.) Sirius' binary companion. Sirius has a white dwarf companion, known as Sirius B. This star wasn't always a white dwarf, however! The way most Sun-like stars work is that they burn their fuel until they're exhausted, and then they expand tremendously and become red giants.
If Sirius B was a red giant 2000 years ago, then the Sirius system would have appeared extremely bright and red! But there's a tremendous problem: red giants live too long! Once a star is done being a red giant, it blows off its outer layers into a planetary nebula, and the center collapses into a white dwarf, like the Cat's Eye Nebula, below.
There is no evidence for a planetary nebula, and the timescale for this process to happen is measured in the millions of years, not the hundreds or thousands. Therefore, this idea, although incredibly interesting, cannot be correct.
3.) Maybe Sirius is a trinary star system. This would actually work, and -- perhaps most importantly -- it's observationally feasible! How, you ask? Imagine the Red Giant case from case #2. If there were another, denser star close to Sirius B (such as a neutron star or black hole), it could start stealing mass from the Red Giant!
This process could be extraordinarily quick, and could feasibly strip Sirius B bare in just a few thousand years, leaving behind a cold, dead, white-dwarf core.
We don't yet have the technology to resolve Sirius B to the accuracy necessary to determine whether there is a third star close enough in to account for this, but what an interesting possibility!
It's very easy to dismiss someone else's observations, and most scientists do dismiss this ancient set of claims that Sirius was once red. But that doesn't mean it isn't worth taking a look at; if we do, in fact, discover a trinary companion to Sirius A and B, we'll be able to point to these ancient observations and actually verify that they were valid! It's definitely an outside-the-box claim, but this is one that may turn out to be right!
Artists can color the sky red because they know it's blue. Those of us who aren't artists must color things the way they really are or people might think we're stupid. -Jules Feiffer
Last semester, I was teaching my introduction to astronomy class, and part of the coursework was that each student had to choose a unique research topic and write a research paper based on that topic. Topics varied from cosmology to relativity to the space program to individual planets, but one choice captivated me so much that I bring my version of it to you now.
Astronomy was, arguably, the very first science that was approached scientifically. Since ancient times, astronomical observations were made first, and then models were made to explain those observations. Perhaps the most famous ancient astronomer, Ptolemy, wrote in his Almagest a list of six very bright red stars in the sky.
These six stars were as follows, with images above their descriptions:
1.)Betelgeuse, which is a red supergiant and the ninth brightest star in the sky.
2.)Antares, which is also a red supergiant and is the 16th brightest star in the sky.
3.)Aldebaran, an orange giant that's the thirteenth brightest star in the night sky,
4.)Arcturus, an orange giant, variable star that is the third brightest star in the sky.
5.)Pollux, another orange giant (which looks a little yellower than the others) and the 17th brightest star in the sky. And finally...
6.)Sirius, the single brightest star in the night sky. Only, take a look at Sirius up there. Does something strike you as different about Sirius from the other five? Yes, they're all very bright, but Sirius, unlike the others, looks blue!
Don't believe your eyes? Take a look at Hubble's view of Sirius:
Yep, that's anything but red. In fact, Sirius was used -- as far back as ancient China -- as the standard for "white".
Is it possible that Ptolemy made a mistake? If so, he's not the only one. Horace, Seneca, and Aratus -- all writing in Europe around 2000 years ago -- each describe Sirius as being red in color. (And do so up to 200 years before Ptolemy.) Cicero and Germanicus also translated Aratus and wrote about his work, and felt no need to mention Sirius' redness as being bizarre at all.
But is there any way to make sense out of this? Is it possible that Sirius once really was red, and has changed color to blue-white over only the past 2000 years? Or are all of our ancient sources here -- including Ptolemy -- simply unreliable? Moreover, what to make of the other ancient sources (mostly from China) that contradict this?
The explanation will be forthcoming on Wednesday, but in the meanwhile, I'd like to know your take based on the evidence I presented here. Ptolemy is pretty reliable as far as sources go, and the fact that all six stars are bright and that five of them are definitively red are pretty strong circumstantial evidence that Sirius once was, too. On the other hand, we have some ancient evidence to the contrary as well as a plethora of modern evidence that... well... it isn't red! Pretend you're an astronomer and someone presents this to you.
What would you do? How would you go about deciding whether this was confirmable, plausible, or whether you could bust this myth?
