The FAS Astronomers Blog

  • The Deep Sky

    FAS Astronomers Blog, Volume 30, Number 8. When most of us start out in astronomy, we usually focus first on learning the Night Sky. This is followed by the purchase of a telescope and a few backyard sessions spent looking at the Moon and planets. Then we might follow by observing a few stars. However,…

  • Sagittarius A* and the Event Horizon Telescope

    FAS Astronomers Blog, Volume 30, Number 7. Some 26,000 light years away, between the constellations Sagittarius and Scorpius, is the center of the Milky Way galaxy. Our galactic center is extremely dense with stars packed in much tighter than here in the galactic outskirts. The editors of EarthSky note that it would outshine a full…

  • The History of the Universe

    FAS Astronomers Blog, Volume 30, Number 6. This is a story of the Universe. The Universe is big, really big. It also has an interesting history, although one where lots of things happened in the first three minutes or so before everything settled down to a 13.8-billion-year timeline stretching up to the present. I guess…

  • Stars

    FAS Astronomers Blog, Volume 30, Number 5. Stars are huge balls of hydrogen plasma powered by nuclear fusion reactions at their core. Stellar Distances Except for the Sun, which is 93 million miles away, stars are a vast distance from us. Therefore, it isn’t always practical to measure these distances in miles, so astronomers use…

  • Astrology to Astronomy

    FAS Astronomers Blog, Volume 30, Number 4. I don’t know how many times I talk to someone who knows that I have an interest in Astronomy, but they refer to it as Astrology. Well Astrology does have something to do with the night sky and, from an historical standpoint, it is related to astronomy. Both…

  • Cosmic Distances, Stellar Brightness, and The Hubble Constant

    FAS Astronomers Blog, Volume 30, Number 3. The Hubble Constant The Universe is expanding. The farther a galaxy is from us, the faster it is moving away from us. We measure this expansion using something called the Hubble constant, which is the rate with which galaxies are receding from us as a function of their…

  • Project Mercury

    FAS Astronomers Blog, Volume 30, Number 2. Sixty years ago this month (February 20, 1962), Astronaut John Glenn became the first American to orbit the Earth. He did so as part of NASA’s Project Mercury. This is the story. On October 4, 1957, a small round ball called Sputnik was launched into orbit by the…

  • Dark Energy

    FAS Astronomers Blog, Volume 30, Number 1. In a previous article, I explored the Standard Model of Particle Physics and discussed what ordinary matter is made of. It can be a bit confusing because of the different ways to look at it. Matter is made up of atoms, which are composed of protons, neutrons, and…

  • Year End Summary 2021

    Young Astronomers Blog, Volume 29, Year End. I hope you enjoyed the Young Astronomers Blogs for 2021. Just in case you missed a few, below is a summary of the articles for the past two years. This year (2022) marks the 30th year for the Young Astronomers Newsletter. Although, over the past two years, the…