Starts With A Bang!

The Universe is out there, waiting for you to discover it.

Finding the first atoms in the Universe

"In theory, extraordinarily isolated clumps of matter, whose mass totals something like only 0.0001% of our Milky Way Galaxy, may survive without forming any stars at all, and without being polluted by any nearby post-stellar mass, for well over a billion years. But if we wanted to find one, we’d have to be incredibly lucky. From the time the Big Bang first was proposed as a theory in the 1940s, we didn’t have that luck for years, and then decades, and then for generations.

But then 2011 came along, and we’ve had two strokes of luck that serendipitously have given us the luck we’ve been waiting for!”

The Big Bang has, among its predictions, three cornerstones: the Hubble Expansion of the Universe, the Cosmic Microwave Background, and the abundance of the Light Elements due to Big Bang Nucleosynthesis. The first one has been confirmed to spectacular accuracy, and with the COBE, WMAP and Planck satellites, the spectrum and fluctuations in the CMB rule out almost every other feasible alternative. But detecting the abundance of the light elements directly has always run into a difficulty: the formation of stars in the Universe pollutes the intergalactic medium, ruining our ability to see anything “pristine.” We’d have to get incredibly lucky, to find a region of molecular gas that had never formed stars in-between our line-of-sight to a quasar or bright galaxy. For nearly 70 years, that didn’t happen, and then all of a sudden, we found two. The Big Bang stands tall after all!

The Physics of the Death Star

"When you think about it, it should make you really, really glad that matter won out over antimatter in the Universe, and that there aren’t starships, planets, stars and galaxies made out of antimatter out there. The way the Universe is destructing — slowly and gradually — is more than sufficient as-is."

The idea of destroying an entire planet may sound like an unachievable dream of a pathological teenager, as the energy required would be tremendous. To simply overcome the gravitational potential energy binding an Earth-sized planet together would require the entire energy output of the Sun added up over more than a week! But if we could harness a relatively small amount of antimatter — just 0.00000000002% the mass of the planet in question — that would be enough to do it.

Messier Monday: A Miniature Marvel, M70

"This might strike you as strange: Messier 69 and Messier 70 are separated by only 1,800 light-years or so, they’re both close to the galactic center and close to the same age, but Messier 69 — which is slightly older than Messier 70 — has five times the heavy elements found in its neighbor! Why would one be so metal-rich and the other so metal-poor? Because Messier 69 always remains close to the galactic center, while Messier 70 moves in-and-out in a highly eccentric orbit!"

A member of the original catalogue of “not-a-comet” objects was where the telescope was pointed when the comet of our lifetime was discovered! Come say hello to Messier 70 this Messier Monday!

Everything is different now

"To those of you who read Starts With A Bang regularly, you probably noticed that I didn’t write my regular Ask Ethan column this week, I didn’t respond to your Comments of the Week and I didn’t have a diversion for you this weekend. I didn’t want another day to go by without you having an explanation, but I also don’t think I could’ve written this before today. I hope you understand. And I hope that when you think about anyone you ever loved who’s gone, you remember them at their happiest, when they were the most full-of-joy and life that you ever saw them."

Goodbye, Cordelia. I miss you like hell.

The Green Flash

"Given a clear path to the horizon — such as over the ocean — this means that there’s a slight region of space just above the reddened Sun where only the shorter wavelength light is visible!

And when that happens, in addition to the normal color gradient that comes with a sunset, you can also get a small, separate region above the disk of the Sun that appears yellow, green, or even blue! (And much fainter than the rest of the Sun!)”

During sunset, the Sun appears to redden, dim, and eventually sink below the horizon. Every once in a while, a rare phenomenon emerges along with it: a green flash, where a greenish-colored beam of light appears just over the Sun. What causes it? One of the most beautiful natural phenomena our planet has to offer, explained in glorious detail.

There’s no such thing as a Supercluster

"Surely you’ve heard the term supercluster before, where our Milky Way and local group are part of a giant cosmic structure that includes the other nearby galaxy groups and the giant, nearby Virgo cluster, making up our local (Virgo) supercluster. And our supercluster is just one of many, that themselves are arranged together, forming an even larger structure!"

You may have just heard that we’ve mapped out our supercluster of galaxies — Laniakea — to unprecedented accuracy, identifying a region 500 million light-years in diameter that’s responsible for our local group’s motion through space. While it’s an amazing feat of astronomical mapping and cluster identification, calling a structure like this a “supercluster” implies that, in some way, the galaxies, galactic groups and galaxy clusters that make this up are in some way bound together. But this is in no way the case! Come find out why “superclusters” aren’t so super after all

The Planets that Never Were

"Before such delicate instruments were perfected, astronomers attempted a cruder approach to planet hunting called the astrometry method. It involved tracking a star’s movements through the sky, subtracting effects due to Earth’s motion, and looking for minuscule, rhythmic variations that could be chalked up to a planet’s pull."

In 1992, scientists discovered the first planets orbiting a star other than our Sun. The pulsar PSR B1257+12 was discovered to have its own planetary system, and since then, exoplanet discoveries have exploded! But before that, in 1963, decades of research led to the much-anticipated publication and announcement of the first exoplanet discovered: around Barnard’s star, the second-closest star system to Earth. Unfortunately, it turned out to be spurious, and that in itself took years to uncover, an amazing story which is only now fully coming to light

Messier Monday: The Teapot-Dome Cluster, M28

"A collection of eight stars stands out in this region of the sky, not because they’re the brightest stars around, but because they have a distinctive pattern to them that we recognize as very similar to a common object here on Earth. We call such a collection of stars an asterism, and the teapot is one of the most recognizable ones. And the star at the very top of the teapot’s lid — Kaus Borealis — has a secret less than a single degree away from it."

What globular cluster is home to the first pulsar ever discovered in one? Learn about it on today’s Messier Monday!

The Inconstant Moon

"My goal in explaining these lunar phenomena is not to dismiss the hype, but rather to deepen your understanding and appreciation of our celestial companion. I see the Moon as a great example of how amazingly dynamic our Universe truly is, something we can’t often comprehend as most things that change do so on such dramatically long (dare I say astronomical) timescales that they are often imperceptible to us."

Tonight might be the final Supermoon of the year, but the Moon’s story — and the science behind it — is going to be super all year long! A great explainer by Summer Ash!

Saving Salmon… with a Cannon!

"Now in September, the first Salmon Cannons (yes, they are actually called Salmon Cannons) were successfully tested this past June at Washington’s Roza Dam, and are poised to rocket salmon onto trucks where they will be taken farther upstream than they’ve naturally been in a long time. If this, too, proves to be successful, the Salmon Cannon could be exactly what’s needed to restore the fish of the Columbia River to their natural, original runs!"

Hydroelectric dams are one of the best and oldest sources of green, renewable energy, but — as the Three Gorges Dam in China exemplifies — they often cause a host of environmental and ecological problems and challenges. One of the more interesting ones is how to coax fish upstream in the face of these herculean walls that can often span more than 500 feet in height. While fish ladders might be a solution for some of the smaller dams, they’re limited in application and success. Could Whooshh Innovations’ Salmon Cannon, a pneumatic tube capable of launching fish up-and-over these dams, finally restore the Columbia River salmon to their original habitats?