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esiegel | January 9, 2016"In this first testing ground of the atomic bomb I have seen the most terrible and frightening desolation in four years of war. It makes a blitzed Pacific island seem like an Eden. The damage is far greater than photographs can show." -Wilfred Burchett
The news has been aflame with reports that North Korea detonated a hydrogen bomb on January 6th, greatly expanding its nuclear capabilities with their fourth nuclear test and the potential to carry out a devastating strike against either South Korea or, if they're more ambitious, the United States.
Image credit: TV screenshot of CNN’s The…
esiegel | January 2, 2016"Oh, yes — I know you. There was a time you looked at the stars and dreamed of what might be." -Star Trek: Nemesis, spoken by Jean-Luc Picard
The stars call to us through the ages, with each and every one holding the promise of a future for humanity beyond Earth. For generations, this was a mere dream, as our technology allowed us to neither know what worlds might lie beyond our own Solar System or to reach beyond our planet. But time and development has changed both of those things significantly.
Image credit: NASA, 1981. A remote camera captures a close-up view of a Space Shuttle Main…
esiegel | December 26, 2015"They say it all started out with a big bang. But, what I wonder is, was it a big bang or did it just seem big because there wasn't anything else drown it out at the time?" -Karl Pilkington
Looking out at the distant stars, galaxies and radiation in the Universe today, we've been able to determine not only what it's made out of, but how long it's been since the Big Bang: 13.8 billion years. Put all that information together, and you can also figure out how large the observable part of that Universe is today. From our point of view, it appears to extend for 46.1 billion light years in all…
esiegel | December 19, 2015"...in every kind of chemical change no loss of matter occurs [...] in all the varied modes of physical change, no loss of energy takes place." -Sir Henry Enfield Roscoe
When it comes to the physical laws of the Universe, perhaps the most unbreakable of all seems to be the law of conservation of energy. In every mechanical, chemical, or even nuclear reaction, the total amount of energy, when all sources are considered, appear to be conserved.
Image credit: NASA / SDO.
Yet in General Relativity, no strict definition of energy exists. So when the Universe expands, the photons within it get…
esiegel | December 12, 2015"The farther we peer into space, the more we realize that the nature of the universe cannot be understood fully by inspecting spiral galaxies or watching distant supernovas. It lies deeper." -Robert Lanza
When you take a look at a spiral galaxy in the night sky, it seems obvious that the stars on the inner parts of the galaxy are going to orbit in less time than the stars in the outer part. This turns out to be true, something we've figured out even though the timescales for galaxies to complete a full revolution are far longer than we've ever been able to observe.
Image credit: ESO, taken…
esiegel | December 5, 2015"Maybe that is our mistake: maybe there are no particle positions and velocities, but only waves. It is just that we try to fit the waves to our preconceived ideas of positions and velocities. The resulting mismatch is the cause of the apparent unpredictability." -Stephen Hawking
Black holes are the densest, most compact objects in the Universe, with anywhere from a few to many billions of solar masses of material concentrated into a singularity. At a certain distance away from that singularity, every black hole has an event horizon: a region of space from within which nothing can escape, not…
esiegel | November 27, 2015"We are not like the social insects. They have only the one way of doing things and they will do it forever, coded for that way. We are coded differently, not just for binary choices, go or no-go. We can go four ways at once, depending on how the air feels: go, no-go, but also maybe, plus what the hell let's give it a try." -Lewis Thomas
One of the most important characteristics of a planet, at least according to the IAU definition, is that it clear its orbit of all other bodies. But if we allowed for a special caveat -- the possibility of two similarly-sized objects sharing the same orbit…
esiegel | November 21, 2015"Twinkle, twinkle quasi-star.
Biggest puzzle from afar.
How unlike the other ones.
Brighter than a billion suns.
Twinkle, twinkle, quasi-star.
How I wonder what you are." -George Gamow
One of the most interesting classes of objects in the entire sky is one that's invisible to the naked eye, yet appears brighter than anything else in radio wavelengths: the quasar. Originally coined as an acronym (QSRS) for Quasi-Stellar Radio Source, these were later determined to be incredibly energetic sources of accelerated matter powered by a supermassive black hole.
Image credit: Aurore Simonnet, NASA /…
esiegel | November 14, 2015"Never look down to test the ground before taking your next step; only he who keeps his eye fixed on the far horizon will find the right road." -Dag Hammarskjold
One of the great discoveries of the past few decades was that of a supermassive black hole at the center of our Milky Way. No longer was it mere conjecture or unverified theory; observations in the X-ray, infrared, radio, and of stars orbiting a central, non-luminous point all indicate the presence of a 4 million solar mass black hole at a location known as Sagittarius A*.
Image credit: X-ray: NASA/UMass/D.Wang et al., IR: NASA/…
esiegel | November 6, 2015"In theory, there's no difference between theory and practice. In practice, there is." -Yogi Berra
Scientific theories are a dime a dozen, yet only the most successful have a large range of validity, hold up to many disparate lines of evidence, and stand the test of time. Inevitably, our explorations go beyond that range of validity, and a new theory must come along to supersede them.
Image credit: NASA / STScI / A. Felid.
But does that invalidate the old theory? And does that mean it would be irresponsible to bet your life that the idea you're working on is correct? While no theory can…
esiegel | October 31, 2015“End? No, the journey doesn’t end here. Death is just another path, one that we all must take. The grey rain-curtain of this world rolls back, and all turns to silver glass, and then you see it.” -J.R.R. Tolkien
There's a realization we all face at some point in our lives: that not only are we going to someday have our lives come to an end, but that everything that exists in the Universe will cease to be in its current form. All life will wither away, the last stars will burn out, the galaxies themselves will be driven apart from one another, the individual stars and planets will be ejected,…
esiegel | October 23, 2015“Unless one says goodbye to what one loves, and unless one travels to completely new territories, one can expect merely a long wearing away of oneself and an eventual extinction.” -Jean Dubuffet
The Universe is in its heyday right now: hundreds of billions of galaxies are visible from any point, clustered together in a glorious cosmic web, with millions, billions or even trillions of stars burning inside of each one. Yet none of this will last forever.
Image credit: the small star forming region NGC 346, from A. Nota (ESA/STScI) et al., ESA, NASA.
If we peer into the far future, any…
esiegel | October 16, 2015“In such moments, offering up his heart at the hour when the flowers of night inhale their perfume, lighted like a lamp in the center of the starry night, expanding his soul in ecstasy in the midst of the universal radiance of creation, he could not himself perhaps have told what was passing in his own mind; he felt something depart from him, and something descend upon him, mysterious interchanges of the depths of the soul with the depths of the universe.” -Victor Hugo
The night sky is a memorable, inimitable sight. With the exception of the planets, the stars that shine so brightly and…
esiegel | October 9, 2015“Everyone has his dream; I would like to live till dawn, but I know I have less than three hours left. It will be night, but no matter. Dying is simple. It does not take daylight. So be it: I will die by starlight.” -Victor Hugo
Whether you're at rest or in motion, you can be confident that -- from your point of view -- the laws of physics will behave exactly the same no matter how quickly you're moving. You can move slowly, quickly or not at all, up to the limits that the Universe imposes on you: the speed of light.
Image credit: Noreen of http://thecampgal.com/2014/06/17/flashlight-…
esiegel | September 25, 2015“What is wild cannot be bought or sold, borrowed or copied. It is. Unmistakeable, unforgettable, unshamable, elemental as earth and ice, water, fire and air, a quintessence, pure spirit, resolving into no constituents.” -Jay Griffiths
When you think about the frontiers of scientific knowledge -- on the border between what's known and what's unknown -- you have the phenomena that we know exist, yet that we can't fully explain. This includes the matter-antimatter asymmetry, the inflationary origin of our Universe, dark matter and dark energy, among others. Yet two of these, inflation and dark…
esiegel | September 18, 2015“To me there has never been a higher source of earthly honor or distinction than that connected with advances in science.” -Isaac Newton
If Newton truly meant that sentiment, perhaps he would have been happy to find out that his theory of gravitation -- which stood unchallenged for over 200 years -- was superseded a century ago by Einstein's general relativity. Not only did Einstein's theory reproduce all the successful predictions of Newtonian gravity, but where the predictions differed, Einstein's agreed with observations where Newton's did not.
Image credit: Wikimedia Commons user…
esiegel | September 11, 2015“[W]hat Fermi immediately realized was that the aliens have had more than enough time to pepper the Galaxy with their presence. But looking around, he didn’t see any clear indication that they’re out and about. This prompted Fermi to ask what was (to him) an obvious question: ‘where is everybody?’” -Seth Shostak
When you consider that there are definitely millions of planets in the habitable zones of their stars within our Milky Way galaxy alone, the possibility that there's intelligent life on at least one of them, right now, is tantalizing. But we're in our technological infancy, relatively…
esiegel | September 4, 2015“There is a fifth dimension, beyond that which is known to man. It is a dimension as vast as space and as timeless as infinity. It is the middle ground between light and shadow, between science and superstition.” -Rod Serling
Of course, despite our best theoretical hopes, we know only of four dimensions -- three space and one time -- that exist in our Universe. But what if there not only were a fourth spatial dimension, but it presented itself to us by growing from a microscopic, undetectable state, and then shrank back into one on an annual basis?
Image credit: Paul Falstad’s 3-D Vector…
esiegel | August 28, 2015“Thus it seems Einstein was doubly wrong when he said, God does not play dice. Not only does God definitely play dice, but He sometimes confuses us by throwing them where they can’t be seen.” -Stephen Hawking
You've no doubt heard that Stephen Hawking is claiming that the black hole information paradox has now been resolved, with the information encoded on the event horizon and then onto the outgoing radiation via a new mechanism that he'll detail in a paper due out next month, along with collaborators Malcom Perry and Andrew Strominger.
Image credit: TU Wien.
Only, that's not really what'…
esiegel | August 21, 2015“The total number of people who understand relativistic time, even after eighty years since the advent of special relativity, is still much smaller than the number of people who believe in horoscopes.” -Yuval Ne’eman
It's been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we're seeing it as it was in the past. Its age -- as it appears -- is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old.
Image credit…