Cosmic rays are incredibly powerful invisible particles, and we can’t be sure where they come from. Not much in the way of a comforting thought, but it makes for a cosmic mystery that astronomers have been trying to solve for decades. And now they have come one step closer. Here’s what we do know. Cosmic rays are energetic atomic nuclei travelling at near the speed of light. They hit our atmosphere and rapidly interact with the molecules there to break into billions of smaller, less energetic particles that shower down on the life on Earth, without giving us much notice...
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...
Space seems dark to our weak human eyes. Most of the night sky is the blackness between stars. But in this darkness lies an endless number of photons, travelling in all different directions. These photos form background radiation, in three wavelengths in particular. You’ve likely heard of the Cosmic Microwave Background (CMB), it there is also a Cosmic Optical Background (COB) and a Cosmic Infrared Background (CIB). The COB is explained by the immense number of stars in the Universe. It’s a diffuse glow across the entire sky. The CMB is the leftover radiation from hot plasma that existed when the Universe...
Let me ask you, when you look at the stars on a cold, clear night, what do you see? Diamonds sparkling? Shapes? I do see those things, but I also see so much more. When I look at the stars, I see a thousand generations of humans looking up in wonder, writing shapes in the dirt and telling incredible stories of brave heroes, ferocious beasts, and important lessons. I see our common ancestors using the sky to predict the weather, the seasons, and even the coming of the end of the world. They were looking at a comet in the...
Honestly this could be the name of a new TV show, similar to ‘when buildings collapse,’ or ‘here’s what Kim Kardashian did today.’ I’ll take the colliding galaxies, simply because they can hold my attention longer. Galaxy collisions are some of the most massive and long term events in the universe. The result is the formation of billions of stars, the change in orbit of Billions more, and the complete restructuring of a galaxy. Since we see a snapshot of the Universe whenever we look at a single galaxy, we tend to see collisions happening at all stages of the...
The only way we can understand the cosmos is to find new and innovative ways to interpret the light we capture from it. Using the largest and most technologically advanced telescopes in the world, we peer deeper into space, further back in time, and see photons that have spent eons travelling to Earth. If we can get rid of all of the other light from closer objects, and zero in on this distant light, we can begin to understand what was present at the beginning. Using data from deep sky surveys conducted by the Hubble Space Telescope (HST), astronomers from...
I just discovered a new YouTube channel that has been running for awhile. It has astronomers from all over the world who talk about their work on the biggest and most intense pieces of telescope technology that we have on this Earth. If you have a bit of time, a bit being about 15 minutes, you’ll want to check it out!
Lurking in the depths of a galaxy, hidden from human eyes, lie millions of monsters. They could swallow you up in an instant, sealing you off from the outside world and devouring you atom by atom. This sounds like your typical Hollywood monster movie, but with millions of black holes hidden throughout the galaxy, its more real than you might think. Supermassive black holes, the largest ones that reside at the centers of galaxies, are much easier to see. They are devouring gas and dust rapidly, resulting in bright emission across the electromagnetic spectrum, especially in x-rays. For many galaxies,...
If you could see through the lens of a very powerful telescope, to an area of sky the size of a grain of sand held at arm’s length, a new universe would be revealed to you. For in that tiny patch of seemingly empty sky, there are thousands of galaxies visible, albeit with many hours of light collection. Observing the most distant of these galaxies, at the edge of the universe, allows us to estimate the number of Galaxies present in the distant past, when the universe was very young. As our observations improve, and our ability to simulate the conditions of the...
Massive star clusters can pop into existence in a matter of a few million years, a very short period of time on astronomical time scales. They consist of hundreds or thousands of massive, bright, hot stars that will live relatively short lives of a few hundred millions of years. Using the Atacama Large Millimeter/Submillimeter Array (ALMA), astronomers have discovered a vanishingly rare molecular cloud of highly dense gas, containing no stars. It is poised to become a massive star cluster, and we found it in its infancy. “We may be witnessing one of the most ancient and extreme modes of...
