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...
If there’s one true fact about every single gas giant planet ever observed, around the Sun or other stars in the Galaxy, it’s that they all are mainly composed of Hydrogen. Even though the giants of our solar system such as Neptune and Jupiter seem very different, it is Hydrogen that primarily composes them. The difference is in the details though. The blue colour of Neptune is due to the presence of Methane, and even then it only makes up 1.7% of Neptune’s mass. But Hydrogen is light. Wouldn’t giant planets like hot Jupiters lose their Hydrogen from being blasted...
After yesterday’s post about some data that has caused us to rethink a theory, I wanted to follow it up today with an even bigger bit of data that could substantially change an even bigger theory. Dark energy was discovered as a large-scale repulsive force in the universe that is responsible for the acceleration of its expansion. It was discovered by looking at type 1a supernovae in distant galaxies. since the supernovae all explode with the same mass limit, they appear to all have the same intrinsic luminosity. If we know how bright they actually are, we can compare them...
More than two-thirds of stars are not solitary like our Sun. They are binary systems, meaning they contain two stars that orbit each other about their common centre of gravity. Stars like our Sun are much more rare, and we are not sure what the difference in formation is between binary and solitary systems. Binary systems are much more useful from a scientific perspective, as we can study their orbital period and separation to infer a wide range of properties such as masses and distances. A special class of stars, called RR Lyrae variable stars, have puzzled astronomers for years...
The Milky Way Galaxy has about 26 associated satellite galaxies, which is strange to imagine, since we think of a galaxy as a massive collection of Billions of stars. The dwarf galaxies are not easily visible since they are small, so they tend to blend in with the background of Milky Way stars that are much closer. You might also notice from the above image that the dwarf galaxies are distant, lying beyond the 100,000 light year scope of our large spiral home. Most of them likely originated in the turmoil of protogalaxy collisions that occurred billions of years...
