The FAS Astronomers Blog

  • The Earth’s 2nd Moon?

    FAS Astronomers Blog. Volume 32. Number 11. Although, it really didn’t count as an official moon, a small object entered into a temporary orbit about the Earth and was called “the Earth’s second moon.” Asteroid 2024 PT5 was captured by the Earth’s gravity on September 26, 2024. It stayed around for a couple of months…

  • Auroras

    FAS Astronomers Blog, Volume 32, Number 10. If you live way up north, you might look up at the night sky from time to time and see shimmering lights stretch across the horizon. These are what we call the northern lights. They are also known as auroras. Auroras occur all the time. We don’t see them…

  • 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…

  • The Discovery of Neptune

    FAS Astronomers Blog, Volume 32, Number 8. Neptune is the only planet to be discovered through mathematical analysis. The orbit of Uranus was determined to be perturbed by an unknown object farther out in the Solar System, which astronomers thought might possibly be a new planet.  In 1792, Jean Delambre published tables of planetary positions. It…

  • 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…

  • What’s in the name Uranus?

    FAS Astronomers Blog, Volume 32, Number 5. William Herschel was the most famous astronomer of the eighteenth century. So much so, that Heinz Pagels called the first major section of his book Perfect Symmetry as “Herschel’s Garden.” On March 13, 1781, Herschel accomplished something that no one else had done in modern times. He discovered…

  • 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…