There are many unexpected perks of being a physics graduate student and having, how should I put it, a “graduate student work schedule.” One of my favorites is when I go home for the night (or morning?). Every time I walk through my department’s doors I am greeted by what has become a familiar sight:
[Image: Mine]
Do you see it? Look carefully. How about now?
[Image: Mine]
Do you see the little dot? That, my dear friends, is a planet. It is sitting over 373 million miles (601 millions kilometers) away from us but I can see it with my naked eye, from the steps of my department, through my phone’s camera lens! However, 373 million miles is no small distance, it is about 4 times the distance between here and our Sun. That distance is so large it takes about 35 minutes for light shining off the planet to reach us compared to the 8 minutes it takes for light from the sun to reach us. As small as it looks, that pale white dot is over 1300 times the size of this rock we call home, yet it is still only 1/1000th the size of the sun. Do not let this fool you, though. Jupiter can hold its own when it comes to causing the sun to wobble off its axis. Its largest moon alone is 25% larger than the planet Mercury and even twice the mass of our moon.
Before I get carried away, let’s take a step back:
[Image: NASA’s Juno Mission]
Sorry, by a step I meant 6 million miles (9.66 million kilometers). This image was taken in August by Nasa’s new Juno satellite, en route to a cozy spot orbiting Jupiter, and tasked with studying the gas giant. By the way, that not-so-pale dot on the left is Earth. You and I both have a about 50% chance of being in the photo. That smaller, pixel-sized object is our moon. 🙂
If you want to see a really pale blue dot, here is a classic:
[Image: NASA’s Voyager I Mission]
Tucked away in that right-most ban is a small, sub-pixel dot. That is us, again. This real photo was taken by NASA’s Voyager 1 satellite back in 1990. Not impressed? Well consider this: the photo was approximately taken here (green band):
[Image: Wikimedia]
Voyager was around 3.7 billion miles (6 billion kilometers) away from the Earth when the photo was taken. That is just under 40 times the distance between us and the sun. Currently, Voyager I is about three times as far (11 billion miles /17.9 billion kilometers).
And to think, here we are on this quaint little planet, in this nice little spot under the sun, surrounded by neighbors (by neighbors, I mean neighboring star systems), tucked away into a little arm in the Milky Way Galaxy.
[Image: Wikimedia]
You know what? That is our galaxy. We live there; it’s home. Think of that feeling you get when you visit your hometown after having been gone for so long. It is the beginning of the holiday, so it should not be too difficult to conjure up that little tingle. In that spiral arm of our galactic city is the neighborhood where we all grew up. It may be just another star system, but to us it’s that place with all the holes in the wall. If some visitor from another galaxy asked us where to go for a little sun, we of course point to Mercury. Where are the best active volcanoes for those die-hard climbers? If you like warm temperatures, I say Venus; if you like things cold, check our Neptune. If you are hungry, go to Earth – no questions there.
[Image: Mine]
At the end of a long day, it is always nice thinking about how big this place is. We humans are really just a small speck in all of the cosmos; however, that just means there is so much more out there worth studying and exploring. Sure, my research is probably only be a small cog in the grand scope of things but it has its place. I find it incomprehensible by just how comprehensible the Universe it, but I suppose that is what makes being a scientist so exciting.
This last picture is another shot of Jupiter taken about 23 hours after the first one and just hours after Madison’s first snow of the season.
Happy Colliding.
– richard (@bravelittlemuon)
P.S. If you have any photos of your favorite stars or planets, send them my way (rruiz AT hep DOT wisc DOT edu). I am happy to post a few up them on here. The only condition is that they be your own work and not pulled from some APOD database. Unless you actually are an astronomer and had some Hubble time, then that totally counts. 😀
Tags: @bravelittlemuon, astronomy, jupiter, voyager
