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...
Today I found a few nice images that I wanted to talk about, and each one revealed something different about the object that was being imaged. I thought it would be a good chance to show everyone how astronomy is really the study of patterns of light, speaking from a minimalist perspective. We learn literally everything about the Universe beyond the solar system from the photons we see. From photons we can deduce the mass, distance, density, composition, behaviour, formation, and evolution of the cosmos. Pretty stellar! (pun intended) Here are some recent images and what we learn from them....