visible
esiegel | August 21, 2013"I am undecided whether or not the Milky Way is but one of countless others all of which form an entire system. Perhaps the light from these infinitely distant galaxies is so faint that we cannot see them." -Johann Lambert
When we look out at the Universe, our view is pretty consistently dominated by the stars within our own galaxy. Although we know that many interesting things lie beyond -- globular clusters, individual galaxies, and rich clusters and superclusters of galaxies -- being in the Milky Way makes it very hard to see beyond it.
Image credit: Richard Payne, of Arizona…
esiegel | February 6, 2013"According to the special theory of relativity nothing can travel faster than light, so that if light cannot escape, nothing else can either. The result would be a black hole: a region of space-time from which it is not possible to escape to infinity." -Stephen Hawking
You may have encountered objects that are the same size as one another, but have very different masses.
Image credit: Basic Science Supplies / © Accelerate Media.
This is because they're made out of different elements. The higher you go in the periodic table, the larger and more massive your individual atoms are, and so…
esiegel | May 26, 2012"This seems to be the law of progress in everything we do; it moves along a spiral rather than a perpendicular; we seem to be actually going out of the way, and yet it turns out that we were really moving upward all the time." -Frances Willard
As spring gives way to summer here in the Northern Hemisphere, one of the most beloved sights of the night sky becomes ever more prominent: the Big Dipper.
(Image credit: NASA, ESA, Z. Levay (STScI) and A. Fujii.)
These seven bright stars shine high above the horizon after sunset, and will continue to do so over the rest of the Spring and all Summer…