The FAS Astronomers Blog

  • Comets

    FAS Astronomers Blog, Volume 32, Number 9. The Solar System is full of interesting objects – planets, dwarf planets, moons, and asteroids. These objects are very predictable and show up month after month and year after year. On the other hand, comets are different. Although, some return on a regular basis, many comets surprise us…

  • Atoms and Molecules

    FAS Astronomers Blog, Volume 32, Number 7. We all were taught that things are made up of molecules, which, in turn, are made up of atoms. Atoms are composed of electrons (with a negative charge) and a nucleus, which contains protons (with a positive charge) and neutrons (with no charge). Electrons are thought to be…

  • How to Pronounce It

    FAS Astronomers Blog, Volume 32, Number 6. Astronomical names are not always the easiest to pronounce. Many are derived from Latin, Greek, or another more exotic language. Star names, in particular, often come from Arabic and from a time when astronomy was kept alive in the Middle East during the dark ages in Europe. There…

  • Gravity

    FAS Astronomers Blog, Volume 32, Number 4. Objects fall to the ground. That’s the nature of things on the surface of the Earth, and everywhere else. Gravity is something that humankind has been familiar with since ancient times. Drop something and it falls to the floor. Jump up and you end up back on the…

  • You Don’t Need to Duck

    FAS Astronomers Blog, Volume 32, Number 3. Just recently, the folks at Live Science published a few articles about the risk of a dangerous asteroid hitting the Earth (see below). Is it time for us to start worrying? Have you heard of NEOs, PHAs, and PHOs? Well, these are Near-Earth Objects (NEOs), Potentially Hazardous Asteroids…

  • Cosmic Microwave Background

    FAS Astronomers Blog, Volume 32, Number 2. Just recently, it was reported in the news that Arno Penzias had passed away at the age of 90. Penzias, along with his colleague Robert Wilson, discovered the birth of the universe.  In the 1940s, There wasn’t any direct evidence of the so-called Big Bang that many astronomers…

  • The Daytime Moon

    FAS Astronomers Blog, Volume 32, Number 1. One of our favorite observation targets is the Moon. Most of the time, we observe it at night. Interestingly, the best time to see features on the Moon isn’t during a full moon – it is much too bright, but during a first or third quarter when you…

  • Asteroid 1, Dinosaurs 0

    FAS Astronomers Blog, Volume 31, Number 15. The dinosaurs ruled the Earth for millions of years. Despite their dominance, the dinosaurs disappeared. The commonly accepted theory is that a large asteroid hit the Earth, resulting in the extinction of over two thirds of the species on the planet. For more on dinosaurs, see three previous…

  • The Case of the Brontosaurus

    FAS Astronomers Blog, Volume 31, Number 14b. When I was growing up, Brontosaurus was almost as famous as T. rex. However, Othniel Marsh made a mistake (maybe). In 1877, he discovered a dinosaur, which he named Apatosaurus ajax (Marsh 1877). Two years later, in 1879, he discovered another similar dinosaur, which he named Brontosaurus excelsus…