Discover the cosmos!Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Discover the cosmos!Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. Explanation:Don’t judge a galaxy by its size. Our home galaxy, theMilky Way, is about 100,000light yearsacross. This huge expanse of space contains hundreds of billions of stars! The smallest galaxies, calleddwarf galaxies, are about 1/10th the size of the Milky Way and only contain a few billion stars. They are also themost common type of galaxyin the whole universe.Today’s imageshows one such dwarf galaxy,NGC 4449, captured by theHubble Space Telescope. NGC 4449 and similar dwarf galaxies aremissing more oxygenthan models predict. This suggests theirstellar windsandsupernovaeare surprisingly effective atblowing awayoxygen and other heavy elements. Turns out these tiny galaxies may play a big role in spreading heavy elements — the building blocks of stars, planets, and life — throughout the universe!Tomorrow's picture:a date in Poland