Big stars tend to stick together. They all require incredibly dense regions in which to form, but once they do, they do a great job of blowing away and ionizing any other gas and dust in the vicinity. This is why nebulas in distant galaxies are great tracers of massive star formation. The bigger and hotter the star, the more UV light it produces, the more it ionized a gas cloud, the more we see gorgeous nebula. So it’s no surprise that when I look at the nebula below, I can guess that the central stars are huge, outweighing our...
Gamma rays are the most powerful form of electromagnetic radiation in the universe. With wavelengths as small at atoms, they usually result from the most powerful interactions known, such as the collision of two particles, or the release of energy from the accretion disk of a black hole. But there is another potential source of gamma rays that has not yet been confirmed: Dark Matter. The leading candidate for dark matter is the theorized Weakly Interacting Massive Particle (WIMP), though it is not as wimpy as its namesake suggests, making up 5 times as much mass as the visible matter...
Sadly no, this time we are NOT talking about Pluto. Astronomer Mike Brown from Caltech, heralded as the ‘man who killed planet Pluto’ has done some new work that might replace Pluto with a better fit for a true ninth planet, one that is ten times the mass of Earth. Now the only problem is finding it. But wait, if we haven’t seen it, how do we know it’s there? Well it certainly showcases the power of science, that an understanding of the true laws of nature can give us incredible predictive power. It started out as a ‘that’s strange’...
We know that galaxies like our Milky Way are far more massive than we can see. The dark matter in the Milky Way makes up 90% of it’s total mass. Another way of saying this is the Mass to Light ratio, comparing the total mass inferred by the rotation speed of the galaxy to the total mass of stars in the galaxy. This ratio, M/L, for the Milky Way, is about 10. But for a galaxy cluster, the M/L ratio is more like 100. Galaxy clusters are not just dense collections of stars and massive galaxies, they are also immense...
Black holes are the most extreme phenomena known in the universe. They are the absolute limit of what gravity and space-time can be twisted into. It’s no surprise that some of the most massive and advanced telescopes in the world are tasked with studying their properties and how they interact with their environment. But maybe there’s a way for you and I to see what a black hole can do, and all we need is a moderate 8 inch telescope and our eyes! Even though black holes generally give off tons of radiation, we need to observe them in the...
In the early universe, there was a huge amount of swirling matter and light that didn’t really have much structure. Compared to today’s much more regular dotting of galaxy clusters and superclusters, the early universe was all over the place. But as will all things, there had to be a first. a first star, a first galaxy, and even a first galaxy cluster. The massive cluster of galaxies known as IDCS J1426.5+3508 is the most distant massive galaxy cluster ever discovered, and it has some interesting properties that point to how it formed and evolved so quickly. One such property is...
Beyond the atmosphere, past the stars we see, farther than the Milky Way, and continuing past Andromeda, we reach the real cosmic ocean. So called because like an ocean on Earth, it is vast, homogeneous, and impossible to navigate by common sense alone. In the cosmic ocean, an impossibly huge amount of space separates island galaxies, whose strong gravity binds them across incredible distances, dictating their course, and forming the largest and most massive structures in the universe: galaxy clusters. Because these immense structures are so vast and so distant, it requires the work of several telescopes to map out...
Dark matter is everywhere. There is way more of it in the universe than the matter we are made of and interact with. Yet for the sheer amount of it, we have no way of determining what exactly it is. It’s as if we didn’t know what air was, and even though we could see it and breathe it, we couldn’t measure it. The most tantalizing part about dark matter is that we can see the gravitational effect it has, and so we can determine how much of it there has to be. Some places in the universe have more dark matter than...
News always reports the records. The biggest, the loudest, the fastest, the first. When it comes to Astronomy, there are so many new worlds to explore and so much new science to learn, we end up breaking records often. Even with Astronomy being the oldest science, the sheer amount of stuff in the universe means there is always something new and surprising to discover. Today’s episode of ‘Biggest, brightest, hottest’ brings us the move massive binary star system ever found, with two huge, hot stars so close together that they are actually touching, merging their atmospheres together. In the Large...
192 Gigabytes. One picture. And I thought the 4 GB Andromeda shot was impressive (okay it still is). But this shot of the Milky Way, the largest single astronomical image ever compiled, is truly staggering in its detail. Showing multiple images taken with different filters, the massive compilation is the culmination of a 5-year observing program by the Ruhr-Universität Bochum. It’s amazing how much detail is shown, as you zoom in across the different features and truly get a sense for the magnitude of our Galaxy, and for the massive population of stars. I have yet to find a way to...
