Astrophotography: Sagittarius and the Galaxy

The challenge of learning astrophotography, and photography in general, is two-fold.  There’s the work you do at the eyepiece, requiring you to choose the right settings for the right shot.  Then there’s the work you do at the computer screen, the post-processing and adjustments.  Ultimately the more important one is the camera work.  If you take a bad photograph, no amount of post-processing will help you, even if you are an expert at it.  It’s like the image is the cake, and the processing is the icing.  No matter how much icing you cover it with, a bad cake is...

Measuring Dark Energy Like a BOSS

When you start to think about the most massive and extreme ‘stuff’ in the universe, you inevitably go to Dark Matter and Dark Energy.  They exist as opposites, one with incredible gravity holding the universe together, and the other a mysterious vacuum energy tearing it apart.  Studying this cosmic tug of war gives astronomers a chance to determine the past and future of the entire universe. To study the immense scale of these two quantities, the Baryon Oscillation Spectroscopic Survey (BOSS) program of the Sloan Digital Sky Survey-III (SDSS) constructed a 3D map of the sky, amounting to a volume...

A Direct Black Hole

How did supermassive black holes form in the early epochs of the universe? More importantly, how did they have enough time to grow as large as they did? The answer requires a very different universe.  And back then, conditions were much different than they are now.  There was a lot of gas, little dust, no stars, and a plethora of dark matter. Astronomers have spent decades observing early quasars, massive active galaxies powered by huge black holes feeding on surrounding gas.  But these galaxies are seen so early in the universe’s history, one starts to wonder how a black hole finds sufficient...

Everlasting Light

Light is beautiful.  It illuminates a world of beauty for us to appreciate while giving us a tool to decipher the riddles of the universe.  In astronomy, it’s always about more photons! Because more photons = more data = better results.  But in an increasingly technological world, more photons can be a bad thing.  Especially when the artificial photons overpower the natural. I was lucky to spend most of my youth living away from the bright lights of the city, but with the sprawling metropolis of Toronto to the South, I could always see the orange glow that blocked out...

Seeding The Supermassive

In the early Universe, things were quite different.  The first stars were much more massive than stars today, and contained mostly Hydrogen.  Astronomers have good ideas about how they formed, but other objects from around this time, namely black holes, are much tougher to account for.  Early black holes were huge, with no explanation for how they grew so large.  “Early” means “first Billion years after the Big Bang,” but even in that time, it’s hard to determine how observed black holes could grow as large as 100,000 solar masses. I say 100,000 solar masses, because that is the mass of two ‘seed’ black holes, discovered...

Black Holes ARE Dark Matter?

Dark matter could be almost anything.  With little data other than how much total dark matter mass exists, we can’t decode much about what individual chunks of dark matter might be made of.  I’ve talked before about Massive Compact Halo Objects (MACHOs) and Weakly Interacting Massive Particles (WIMPs), but these are just two possibilities.  Other theorists have talked about Modified Newtonian Gravity (MNG), where gravity may work differently on the grand scale than it does on our small Earth scales.  Or perhaps it’s something I haven’t seen before.  Maybe what we call dark matter is just a large population of ancient black holes....

Heavy Metal

Where do the heavy elements on the periodic table come from?  The general answer is from what’s called the r-process of stellar nucleosynthesis.   This translates to ‘rapid neutron capture’ being the method by which most of the elements heavier than Iron are formed on the periodic table.  This process requires immense energy and was originally thought to only occur within core-collapse supernova explosions. “Understanding how heavy, r-process elements are formed is one of hardest problems in nuclear physics,” said Anna Frebel, assistant professor in the Department of Physics at the Massachusetts Institute of Technology (MIT) and also a member of...

Falcon Flight to the Galaxy

In the APOD photo from May 14th, it is easy to imagine the rocket launching far away into the galactic disk.  Sadly the rocket can’t traverse the thousands of light years to reach the distant stars, and is restricted to orbiting the Earth. Another beautiful part of this image is the technique involved in producing it.  It required combining two exposures. The first, with low sensitivity to capture the orange rocket trail of the Falcon 9.  The second with high sensitivity and a longer exposure time to capture the faint light of the Milky Way galaxy beyond.  The result is...

A Lonely Universe?

Life in the universe is a fascinating topic.  The simplest question: Are we alone? It breeds so many deeper and more profound scientific questions, like “How many habitable planets are there?” “How likely is life to develop on any given planet?” and “How long can a civilization survive?” We can’t answer them definitively, but we can narrow it down. The Drake equation, shown above, was first developed by Frank Drake, the head of the Search for Extraterrestrial Intelligence (SETI), in 1961.  He took the question of are we alone and made it quantifiable, in a probabilistic way.  It lets us...

Stellar Snowball

The closest star to the Earth, aside from the Sun, is Proxima Centauri, a small red dwarf star that is part of the Alpha Centauri system, roughly 4 light years away.  If you don’t know light years, the distance is a staggering 37,800,000,000,000 Km.  Beyond that our stellar neighbourhood fills in as you move 20 light years in any direction, and by 100 light years, there are dozens of stars around us.  This gives a stellar density of about 0.14 stars per cubic parsec (a parsec is about 3.26 light years), pretty normal in terms of the number of stars in a given...