There have been a lot of headlines going around in the past week that are making people excited. They are stating, with various degrees of enthusiasm, that Jupiter is closer to the Earth right now and so you can see the four Galilean moons with just binoculars! Don't miss it!
This is what I hate about clickbait titles. When I posted to Facebook last night that I was looking at our giant solar system mate, someone commented that they won't be able to see it because of light pollution in the city. And other people are like, "We're missing it because it's raining." But here's the thing: Jupiter might be closer to the Earth right now...but to the untrained eye, it's not really much "closer" than it ever is when it's up in the night sky. You can USUALLY see the four Galilean moons with binoculars, even with a bit of light pollution (they will be tiny pin pricks of light, but they will be there. If you lean on a fence or table when looking through binoculars, you will be steadier and it will be easier to see). The only reason we are closer to Jupiter this week is because we are right between Jupiter and the Sun. So maybe viewing might be a little better, but if you can't see it this week, please don't let that stop you from looking at it another time. I've seen Jupiter at all times when it's visible, and it's always a great thing. If it doesn't work out because of rain or because you need to take a little drive a few minutes out of the city, you can just wait a few days and go out. Hell, you can wait months or even until next year. Jupiter is old. And patient. And pretty set in his ways. He'll still be there. You'll still be able to see things. The number of moons and their positions might change depending on where they are in their revolution around the big planet, but Jupiter is always a nice thing to look at through binoculars.
Now, if you have even a small telescope, you'll be able to see more. You should be able to see the well defined form of the planet itself, and possibly some stripes. With my telescope, (600 mm focal length, aperture 102 mm, plus whatever the eyepiece I use adds), you can see the stripes of the planet clearly, and can distinctly see all four Galilean moons. This image from Sky and Telescope shows what you might be able to see (with 3 out of the four big moons):
I'm still working on the equipment for my astrophotography setup, so hopefully I will have pictures of my own soon.
Some cool facts about Jupiter:
--The Galilean moons were named after the man who first studied them in 1610, Galileo himself. He had no idea what those dots were around Jupiter, assuming them to be stars at first. When he saw how they moved, he was very confused. It didn't take him long, however to realize these bodies were revolving around Jupiter, and that we see it kind of edge on. The names of the individual moons are Callisto, Ganymede, Europa, and Io.
--Jupiter is the biggest planet in our solar system. How big is it? Well, if you put ALL THE OTHER PLANETS COMBINED together, it would STILL be two and a half times bigger. And there are some BIG planets out there--Earth is one of the very smallest!
--For as long as we have studied the huge planet, we still have no real concrete idea of if there is a solid core to the planet, and how big it is under its massive atmosphere. This is because pressures in Jupiter are so high that things that would be solid here on Earth are actually liquid on Jupiter. There are layers upon layers of clouds, each layer with different types of storms. Fierce winds that you and I can't even imagine give Jupiter its banded appearance, and the colors in the clouds are caused by various chemical in active reactions in the atmosphere. We haven't been able to penetrate Jupiter's atmosphere--everything we've sent down there gets crushed and obliterated by the planet's pressure before we can get many readings. So we just have no idea! Our best guess is that there is a molten core at the center that is about as big as 12 Earth masses. And this is surrounded by liquid metallic hydrogen (hydrogen in a form that is conductive, made possible by all that pressure), which is then in turn surrounded by lots of gas and storms.
--The storms on Jupiter are caused and effected more by Jupiter's interior than by any heat from the Sun. In fact, Jupiter radiates 1.67 times the energy it receives from the Sun. This is because it's still got a lot of heat from when it was formed, because it's so massive.
--One of Jupiter's most notable feature's is its great red spot, which is a giant storm. This spot has been visible for at least hundreds of years, if not thousands. We don't know what has caused the storm, but we do know that it changes over time. It's been shrinking. Some day, there might not be a great red spot. There might be more than one some day. Or there will be more small spots. The atmosphere of Jupiter is constantly changing. Here is a time lapse video taken by Voyager 1 showing how Jupiter's atmosphere moves: Jupiter_from_Voyager_1_PIA02855_max_quality.ogv
--Jupiter has a ring system, but it's not very remarkable. It's made of dust, and might only be a temporary feature lasting a few thousand years, unless it's replenished by more collisions from meteoroids into the moons.
--Don't believe those images you see on the internet with the clouds on Jupiter that look like we see clouds on Earth. The closest images we have of Jupiter still look very flat and smooth. Anything that looks like the camera can see wispy clouds and is kind of inside the clouds is fake.
--Jupiter's moon Io is the most volcanically active body in the entire solar system. It has basically turned itself inside out via its eruptions, spewing its insides onto the surface. Some of the material that comes from the volcanic vents on Io is hotter than anything on Venus.
--The moon Ganymede is larger than the planet Mercury.
--Moon Europa is viewed by scientists as one of the most likely places in the solar system to find extraterrestrial life.
--Callisto, the fourth Galilean moon, has one of the oldest and most heavily cratered surfaces in the solar system.
Jupiter is really one of the most fascinating objects in the solar system because a) it's very visible, and b) there is so much more to learn about it. Go to the library and check out some books, or go to NASA's website about Jupiter where they have a ton of information about the planet and its moons, as well as lots of mind-blowing images.
This is a sneak peak example of the science content that will be available on my Patreon! It's free for now, but I would greatly love your support to help make it possible for me to share even more of this stuff with you! Just $2 a month gives you access to ALMOST everything I do there!
Melanie R. Meadors is an author of fantasy, a role playing game designer/editor, and a blogger with The Once and Future Podcast and GeekMom. She also loves science, sewing, music, comics, DMing for a couple of gaming groups…In other words, she’s a professional nerd. You can learn more about her at her website. And if you like what she’s doing here, please support her Patreon!