Field of Science

Showing posts with label galaxies. Show all posts
Showing posts with label galaxies. Show all posts

That's a lot of stars; That's a lot of galaxies

Unless you've had a chance to get away from civilization, way away from civilization, you don't really know what the night time sky looks like because of light pollution. Years ago TPP found himself in the outback of northern Queensland at a quaint place called the 40-mile Scrub. So no lights, no clouds, no humidity, and it was amazing what you could see of this unfamiliar night sky. The scope of our galaxy and the universe it occupies is quite mind-boggling, the more so that this is a Monday morning when the mind is more easily boggled. At any rate here's a link to a photo essay about how many stars compose the Milky Way Galaxy (which BTW means milky). Personally, you should check the accuracy of this report because 200 billion sounds a bit off. And if that isn't enough, then here's a computer generated image of our local galactic super cluster, called Laniakea, and the tiny little dots aren't stars now but galaxies. The bright lines show more densely clustered galaxies, and remember the nearest similar galaxy, Andromeda, is 250 million light years away (and yes, that's not counting the 20 or so smaller galaxy like clusters of stars that are satellites of the Milky Way, e.g., Greater and Lesser Magellanic Clouds). See the nice little comforting "you are here" dot? My Garmin just melted down.

A galaxy longest ago and farthest away


The first thing you need to understand is that the Universe is big, really big, you can’t wrap your brain around it big.  Even though most of our species doesn’t want to admit it, some attempt to grasp just how small and insignificant we are on a cosmic scale is a remarkable intellectual achievement.  Probably this is an affront to the ego of many who gain their sense of superiority by stepping on ants.  So here is a link to a new deep space image that shows a galaxy whose image isn’t just long ago and far away, it is at present the longest ago and the farthest away thing ever seen.  The Hubble ultra deep field is another image you get by taking a very long exposure on a portion of the sky not occupied by stars in our own galaxy, and the amazing thing is that this view, one tiny little segment of the sky shows over 200,000 galaxies, a view that represents just 0.004% of the sky.  You do the math.  Does this give you a new perspective on what BIG means? How amazing that from our teeny tiny mote we know about this.  Now think about that ant's perspective, and step carefully.   

Starry, starry night - more science geeky stuff

These are really pretty amazing images from Starts with a Bang. Galaxies as far as our telescopes can see. If these don't make your world view seem small and parochial, then you really don't get it. Earth is but the tiniest of insignificant motes whose carbon-based, ape-descended intelligent life forms are so utterly primitive that they think themselves the pinnacle of creation.

Leaves you feeling really small - Galaxies Galore!

The Hubble space telescope is just about the niftiest research gadget ever. Here's a deep space image of a galaxy (upper left) that has moved through another galaxy and pulled it apart (tail toward the lower right). Boy, there goes the neighborhood. But what really grabs me about an image like this is you're looking at a tiny fraction of the sky, a portion that includes just a couple of stars with their characteristic cross shape in the foreground, a teeny-tiny part of our own galaxy, and all the rest, all those specks of light receding into the distance, all of them are galaxies. Yes, the Universe is a really, really, really, really big place. Wow!

HT to Starts with a Bang.