Delivering All Kinds of Goodies to Study
Yesterday I talked about how all time is local, in essence, and that the universe’s activity flows along the lines of time. We get to divide the time into units that humans can understand, but the universe itself doesn’t care about how WE divide it up. It just keeps doing its thing.
One of the things it just keeps on doing is showing us new objects. The universe’s structure is divided into large-scale structure — like galaxy clusters and superclusters. These stretch across huge expanses of space. In a given supercluster, light from one “end” of the cluster might travel hundreds of millions of light-years to reach the other “end”. They’re huge.
Small-scale structure “lives” inside the large-scale structure. This would be stuff like individual galaxies, globular clusters, stars, and planets. Humans are at the “micro structure” end of things, comparatively speaking. As we humans keep extending our gaze out beyond our home planet, we keep finding new variations on the “stuff” of the universe. Take planets, for example. Throughout most of OUR history, we only knew about the planets we could spot from Earth’s surface using our trusty Mark I eyeballs. So, we had Mercury, Venus, Mars, Jupiter, and Saturn. That lasted until astronomers invented telescopes and aimed them to the skies — thereby allowing us to extend and magnify our vision.
Today we know of eight planets in our own solar system, dozens of dwarf planets, and — astonishingly to folks who haven’t followed all the latest news — HUNDREDS of planets around other stars.
Last year, I reported from the American Astronomical Society about the first planets found by the Kepler satellite. This year, there will no doubt be more discussion of MORE planets found, followed up by discussions of the characteristics of those planets. They range from supersized hot worlds to places only a bit larger than planet Earth. Kepler is specifically scanning the sky looking for the light signatures of planets that are roughly the same size as Earth. In the process, it has found more than 700 planet candidates and confirmed eight of those candidates as actual planets.
And, the search for planets isn’t limited specifically to Kepler. Ground-based surveys are turning up new planets all the time — and in fact, the first exoplanet was discovered in ground-based data.
This continual discovery of new planets, most in the Earth’s neck of the galactic neighborhood bodes well for the existence of worlds elsewhere in the galaxy — and beyond. That we haven’t seen them yet doesn’t matter. We will.
Beyond the search for other planets astronomers are stretching our collective vision out to study other stars, gathering data that helps them understand how stars work, how they form, how they live, and how they die. In the process, they also learn about how our own star was formed — and the “stuff” of the interstellar medium that is necessary for the formation of stars and planets. This also helps them study galaxies, and the influences that these stellar cities have on the stars and planets and nebulae — and black holes — that populate them. Every discovery uncovers something new that we didn’t know about the universe before. Each finding adds to our collective store of scientific knowledge. What we find is limited only by our ability to see and understand what is discovered. I don’t know about you, but I find this quite exciting. Our universe will keep throwing this stuff at us; it’s our job to step up, take it in, and add to our scientific treasury.