Our Solar System is so much more than just the eight planets that inhabit it. One of the things I learned a bit later in my career as an astronomer (my teenage years; been doing this for awhile) is how unique and diverse the natural satellites are. Our own moon seems somewhat tame, and it’s easy to think the same of all moons. Many of them are boring quiescent rocks with little more scientific value than asteroids, but the largest hide deep and profound secrets that we are just starting to unlock. Four moons in our solar system are larger...
The first exoplanet ever discovered was 51 Pegasi b in 1995. It kicked marked the slow beginning of what would soon become the ‘exoplanet gold rush.’ It meant that for the first time, we had the technological capacity to discover new worlds, and science fiction soon became science fact. 51 Pegasi b was also a very strange planet. A massive Jupiter sized world orbiting very close to its home star. On one hand it was this characteristic that made it much easier to detect. On the other, it showed us that we did not understand planetary system formation as well...
About a year ago I had an idea for a music video. I wanted to take a concept in science and put it to music, making it funny, catchy, memorable, and educational. I wrote out the majority of the lyrics but left it alone for a few months, until I connected with the right friend. My good friend Bob Wegner is a very talented guitarist and audio engineer, and as we spoke about the idea he wanted to be the guy to record it. We spent an afternoon doing the vocals and guitars, and he cleaned it up and made...
How do we measure the rotation speed of a planet? Exactly as you would expect. Watch the surface, look for markable features, and time how long it takes until those features pass the same point again in the future. But how can we possibly nail down this information when the planet has little to no visible surface features. Gas giant planets are great examples of this. Jupiter is a bit easier since it has plenty of storms and separated cloud layers along the planet’s rotation axis, but the other three are much tougher. Aside from hard-to-spot features, gas giants also...
It’s difficult to determine the history of the Solar System. The planets have been in their current orbits for Billions of years, and any signs of prior activity or configuration has to come from leftover geologies of smaller, rocky worlds. It makes it especially difficult when the Billions of interloper asteroids and comets throughout history have to be accounted for, adding to the already complex task. But if there is one thing humanity has going for us it’s the ability to theorize, model, simulate, and test scenarios here on Earth. We can try new ideas and see if they match...
With all the talk of the large geomagnetic storm of the past few days, it’s important to understand that other worlds have beautiful auroral activity as well. Being on Earth and seeing the gorgeous displays that result from our magnetic field protecting us from harmful solar radiation, the best views come from Earth. But there are several other places in our own solar system that have aurora. Jupiter has a massive magnetic field, and its gigantic aurora are visible here. Jupiter’s moon Ganymede is the only moon in the solar system that has auroral activity. Saturn has its own, discovered...
After reaching a deeper understanding of the subsurface ocean of Enceladus just yesterday, a stunning discovery has just been made about the largest Moon in the solar system. The largest moon of Jupiter, Ganymede, contains a subsurface ocean of it’s own. The discovery was made with the Hubble space telescope and a careful study of aurora on the giant moon. That’s right Ganymede has auroral activity. This is because it is the only moon in the solar system with a magnetic field. The magnetic field funnels radiation from the Sun toward the north and south poles, where it ionizes molecules...
At one point in history, let’s say around 1994, astronomers were fairly confident in their understanding of the formation of planetary systems. Even though at the time we hadn’t found any planets orbiting other stars, they had long been theorized, and we figured that systems would form much like our own solar system. Rocky planets in the interior, gaseous giants further out, and a huge icy debris field at the outer edges. And then along came 51 Pegasi b. Half the mass of Jupiter, it orbits its star in only 4 days, far closer than Mercury. It was considered a...
It’s been cold lately. The temperature has fallen somewhere between Hoth and Pluto, and it doesn’t look like it’s going to change any time soon. It seems we complain about the weather no matter the season. It’s too hot, too cold, too wet, too dry, too bright, too dark. We do have a lot of variation in the seasons, but compared to some other planets, Earth is pretty mild in its climate. One such case is the recently discovered Kepler 432b. A massive planet six times heavier than Jupiter with a comparable size, it orbits closer to its parent star than Mercury...
Everything in the universe that has mass, has gravity. It’s easy to understand that the Earth, large as it is, has gravity, which pulls on us constantly, keeping us on terra firma. It’s just as easy to understand that other large objects have gravity, like the Moon, planets, and the Sun. However, it’s much harder to understand that every person on Earth has gravity. Strangely, you exert a force on the Earth, and on every other human. You also exert a force on every rock, tree, and creature that roams the Earth, and they all exert a force on you....
