Why I Love Astronomy (and You Should, Too)
This week, I thought I'd talk about something fun: Astronomy!
If you know me, you probably know that I'm a space science nut. I have been fascinated by astronomy for as long as I can remember. I grew up in a rural area of North Carolina and had a clear view of the night sky with very little light pollution. I would spend hours staring at the night sky, amazed at the beauty and wonder what was out there. I would devour any books I could get my hands on about the planets, galaxies, the universe, and anything having to do with space exploration. I was lucky to have parents who provided access to a lot of books and I quickly became a space junkie.
There are a couple of things about astronomy that I find very satisfying.
For one thing,
anyone can do it.
All you have to do is look up on a clear night and notice what you see. Do this a lot and you start to notice patterns like, "Hey, these stars move differently from the other ones. Let's call them planets." Before we had electricity, that's pretty much what a lot of people did after dark (well, among other things), and they were able to figure out a lot about what is out there just by using their eyes and their brains. With a modest investment in a telescope, your experience can improve dramatically. I live outside of Houston now, and there's a lot of light pollution. I miss those clear nights I enjoyed as a kid, but there's still a lot I can see from here, especially if I know where to look. I have a Carson 114/900 reflector telescope that I've seen on Amazon for under $100. I took that photo of the moon at the top of this post through my telescope from my backyard with my iPhone, so you can see that you don't need fancy equipment or a secluded site to have a good experience.
What really excites me about astronomy is
the more we look, the more we learn.
As we invent better instruments, we continue to make discoveries in places where we've already looked. It's truly amazing. To illustrate this point, I want to talk about one of my favorite objects in the night sky: Jupiter.
Jupiter is very far away.
It's about 778 million km* (about 484 million miles) from the sun. Still, it's the largest planet in our solar system by far. In fact, it's over twice as big* as all of the other planets combined. So, it reflects a lot of light, even so far away. It pretty easy to see in the night sky. I snapped this photo with my phone and you can see Jupiter even in the glare to the lower left of the moon (you may want to click the pic to make it bigger):
People have been watching Jupiter move across the sky for thousands of years and named it for the king of the gods. We could predict its movements, but that was about it. Then, about 400 years ago, the telescope was invented.
When Galileo Galilei observed Jupiter through his telescope, he noticed four objects around Jupiter. This picture was taken with a modern telescope, so it's much clearer than what Galileo would've seen, but he would've seen something like this:
As he continued to observe, he noticed that those four little lights were moving! He realized that these objects were orbiting Jupiter. They were moons! This not only changed our understanding of Jupiter, but our understanding of the solar system. It was the first time anyone had observed anything orbiting an object other than Earth, and allowed the idea of the sun as the center of the solar system to gain traction. Those four moons he discovered, Io, Europa, Ganymede, and Callisto, are referred to as the Galilean moons in his honor.
In the 1970s, NASA began sending spacecraft with scientific instruments out to get a closer look at the planets in the outer solar system.
Just like looking through a telescope for the first time,
we were amazed at what we found.
It turns out that Jupiter has rings, although they are not nearly as fancy as Saturn's, but it was Jupiter's moons that were surprising.
Jupiter has at least 50 moons that we know of (we could see most of those from here), but they're not like our moon. Our moon is a dry, dusty rock (or is it? That's a story for another day.) Some of Jupiter's moons are like worlds unto themselves.
Io, instead of being covered with craters like our moon, is covered with active volcanoes.
Here's one of the volcanos erupting:
We hadn't expected that. You wouldn't expect a small body like a moon so far from the sun to have any heat left this long after the formation of the solar system. So what was causing the volcanoes? Io's orbit brings it closer to Jupiter sometimes and further away sometimes, so the gravity from Jupiter squishes and squeezes Io. This is the same process at work when the moon causes our tides on Earth, but on a giant scale.
This is also happening on another moon, Europa, except that Europa is made of water ice instead of rock.
We can see these cracks on the surface.
It looks at lot like the sea floor on Earth, where the oceanic plates are being pushed apart by the hot magma rising up from the mantle. Do you know what we've found down on the sea floor where that is happening on Earth? A lot of living creatures. Lots of them. What would cause the cracking? Europa is being squished and squeezed like Io. That would cause friction and heat, which means some melting was going on somewhere. Scientists believe a vast liquid or slushy ocean could be beneath the icy crust. Anywhere on Earth where we have found liquid water, we have found something living there, so that's very interesting. In 1995, the Hubble Space Telescope discovered evidence of a wispy oxygen atmosphere on Europa. If we made the effort to look closer at Europa, I'm pretty sure we would be amazed.
The Juno mission is currently on its way to Jupiter and is scheduled to arrive in July of 2016. It's primary science mission is to study how Jupiter formed by mapping its gravity field, magnetic field, and atmospheric structure. The Juno mission has a really cool website with videos about Jupiter, the spacecraft, the mission and a bunch of other fun stuff. You should check it out.
We just have to make the effort to look and we will find something the will blow our minds. Don't even get me started on Saturn.
That's why I love astronomy, so why should you?
There are some criticisms of space exploration.
True. That shouldn't stop us. Staying on this planet is dangerous. Just ask the dinosaurs. Oh, wait. The truth is, we need to understand our place in this universe if we hope to survive.
I hear that a lot, but let's put that in perspective. The Galileo mission to Jupiter, which launched in 1989 and lasted for 14 years, cost US$1.39 billion.
The Galileo mission to Jupiter cost $1.39 billion and lasted 14 years.
That's a lot of money, for sure, but that put over 800 people to work in a challenging scientific, engineering, mathematic, and technological endeavor over those 14 years. Those people were then prepared to go on to solve future problems. They built and sent a robot scientist to Jupiter, after all. And it's really not that much money when you look at the big picture.
We spend less than 1% of our national budget on NASA.
Can you see that little sliver that represents NASA's slice of the pie? It got even smaller in 2014. This is not good news. You know that awesome Curiosity rover that landed on Mars in 2012? There might not be enough money to pay the scientists to keep it going, even though it's designed to last for another ten years. If we don't invest in NASA, we're setting ourselves up to lose. Some will say, "So, what? I don't care about NASA. We have problems on Earth to worry about."
To them I say, you are missing the point.
The more we look, the more we find. The more we find, the more we learn. The more we learn, the better we get at everything!
How do you think we make these discoveries? We make these amazing instruments like Juno and the Cassini Spacecraft at Saturn and International Space Station and the Curiosity Rover on Mars. We learn to solve complex engineering and design challenges. We learn about our place in the universe. We grow as a species from doing the impossible. We inspire a new generation of scientists, explorers, engineers, mathematicians, and inventors who will be prepared to solve the next generation of problems.
Plus, don't you just want to know what's out there? I do.
This is a great time to observe Jupiter. Rising in the east after sunset, Jupiter will follow Orion across the sky for next several weeks. If you have clear skies, take a look. If you have a telescope, see if you can spot any of the Galilean moons. Just be sure to smile, because you never know...there might be something looking back. Happy hunting!
(This image is a screenshot from an iPad app I use called Star Walk to help me find objects in the night sky and I highly recommend it. You point your device up at the sky and it shows you where the stars and planets are. You can even move forward or backward in time to see where things were or will be. Pretty cool.)
Works on this page credited to Adam Brown are licensed under a Creative Commons Attribution 4.0 International License.