A Pale Blue Dot

[Matt]

Astronomy is said to be a humbling profession. The universe is estimated to be 13.7 billion years old and 156 billion light years wide. As of 2006, the observable universe is thought to contain about 7 × 10^22 stars, organized in about 100 billion galaxies, which themselves form clusters and superclusters. The number of galaxies may be even larger, based on the Hubble Deep Field observed with the Hubble Space Telescope. The Hubble Space Telescope has discovered galaxies which are over 13 billion light years from Earth. I am a little upset because I just broke my watch band which is about 1 inch wide.

Here is an awe-inspiring article where world-renowned astronomer Carl Sagan reacts to a photo shot by Voyager 1 in 1990. I hope you enjoy it.

[Savage]

Did you mean to say Astronomy instead of Astrology?

[Matt]

Originally Posted by Steve Pavlina

Did you mean to say Astronomy instead of Astrology?

Fixed. Thank you.

[TechnoGuyRob]

Speaking of the Hubble Telescope...

[Gavin]

A very 'sobering' article and attached photo.

Good to know.

[Shaden]

Fascinating stuff. The universe is absolutely awesome and we shall never really comprehend it's awe-inspiring depths. I am going to make it a priority to learn more about astronomy. You have inspired me!!!

[rock1000]

Some people fear the unknown. Some other worship it. Me, I laugh at it with awe and pride. Why, I am a part of it (and vice versa). Isn't it? .

[Calculusaurus]

I've always found astronomy to be a very humbling study. Carl Sagan summarized this feeling in the most succinct way possible. I actually read that quote often.

[rini17]

Originally Posted by Matt

Astronomy is said to be a humbling profession. The universe is estimated to be 13.7 billion years old and 156 billion light years wide.

That means that the light from most of that 156 billion light years wide universe didn't even came here...amazing. And some scientists say that opposite side of universe continues to expand away from us by faster than light speed, so it won't ever arrive!

I'm interested, if it is possible to go straight on away from our planet and (after few aeons pass, of course ) to arrive back from opposite direction. Maybe law of relativity kicks in and you'd arrive before departure?

Another interesting consideration it that whether matter density in universe stays constant - whether new matter is continually created to offset the expansion. Scientists say that all matter in universe was created from the vacuum so, that the vacuum discharged into matter in steps during early stages of universe. And apparently vacuum still has hidden energy, in fact scientists still doesn't know what makes for 9/10 of all matter in space.