Saturday, January 30, 2016

365 True Things: 307/Astronomy

On the start of my westward return journey this morning, I again passed by the Very Large Array. This time, I turned south for a visit. Fortunately, the grounds open at 8, and I arrived at 8:05 (not that there was anyone around to keep me from wandering around, so far as I could tell). I started by watching a very good 24-minute film, narrated, fittingly, by Jodie Foster (her movie Contact featured the VLA), that describes this radio telescope and some of the work that's done with it. Then I took the walking tour.

I confess I didn't stop to read what I assume is excellent signage. Mostly, I wanted to get up close to one of the twenty-seven antennae, each of which weighs over 230 tons, is 82 feet across, and over 90 feet high. They are very impressive! They get moved around on 82 miles of railroad tracks shaped in a Y, to make up four different configurations.

As for what they actually accomplish—capture very long-wave radio energy from far, far, far away—that's beyond my limited ability to comprehend. All that energy in the universe: radio, microwave, infrared, visible, ultraviolet, x-ray, gamma ray—it's mind-boggling. Never mind the vast distances. Take the galaxy sexily named MACS0647-JD, for example, one of the farthest objects yet known: 13.3 billion light-years from Earth and formed 420 million years after the Big Bang. I mean—those numbers are just meaningless to me. 

Geology also involves big numbers, especially when it comes to the age of the materials of this planet, but at least I can touch dirt and rocks. And the Earth isn't that big, when it comes down to it. The idea that the solid inner core of iron has a radius of 760 miles, while the liquid, outer core of nickel-iron alloy is 1,355 miles thick—those numbers my poor head can pretty much grasp. Then comes the mantle, at 1,800 miles' thickness. And the crust? Between 3 and 46 miles thick. I get that. 

Indeed, the Earth is shockingly tiny in comparison to the vast universe. I don't think I'd ever realized just how tiny until just now.

Because 13.3 billion light-years? That's incomprehensible. One light-year, or about 5.9 x 10^12 miles, is comprehensible. I don't even get 92 million miles (about 500 light-seconds), which is how far we are from the sun, on average.

Be that as it may, I enjoy looking at the sky, even if I can't fathom it. I enjoy knowing a few constellations, tracking the planets as they move throughout the seasons, and looking through a telescope at the rings of Saturn or the Andromeda galaxy. And I enjoy knowing that there are serious scientists who understand far, far, far more than I do about our universe and its origins and makeup. And who get to use the VLA to peer deep into space at specific objects of which I have no ken, and put together a bigger picture of our universe.

I enjoyed my visit, and I took some photos. Here's three of them.

1 comment:

  1. ooh ! . always curious about that for the numbers etc... mind numbing