white dwarf

"A wise old owl lived in an oak The more he saw the less he spoke The less he spoke the more he heard. Why can’t we all be like that wise old bird?" -The Immortal Poet Bromley To your naked eye, the night sky appears littered with thousands of individual points of light: the stars and planets so familiar to us. But through even a small telescope or a pair of binoculars, not only do the number of visible stars increase into the hundreds-of-thousands or even the millions, but a slew of deep-sky objects become visible to us as well. Each monday, we highlight one of the deep-sky objects from…
"You have to have a canon so the next generation can come along and explode it." -Henry Louis Gates When it comes to stars, their fates are very well known. Every single star that's massive enough to fuse hydrogen into helium in its core will someday run out of fuel and die. Image credit: NASA, ESA, F. Paresce, R. O'Connell, & the HST WFC3 Science Oversight Committee. The very brightest and most massive stars -- about 1-in-800 of all stars -- will die in a spectacular, core-collapse supernova when their core burns fuel all the way through iron and finally runs out of room to go. This…
"Man alone is born crying, lives complaining, and dies disappointed." -Samuel Johnson But the stars, as opposed to humans, are born shining, with hundreds (or more) of brothers and sisters, shine ever more brightly over their lifetimes, and die in spectacular fashion. As far as we can tell, here's the past, present and future story of all the Sun-like stars in our galaxy. Bok Globule Barnard 175; image credit by Jerry Lodriguss of http://www.astropix.com/. At some point in the far distant past, every star in our galaxy was once no more than a molecular cloud of gas, with gravity attempting…
"Everyone must leave something behind when he dies, my grandfather said. A child or a book or a painting or a house or a wall built or a pair of shoes made. Or a garden planted. Something your hand touched some way so your soul has somewhere to go when you die, and when people look at that tree or that flower you planted, you're there." -Ray Bradbury Today is Memorial Day here in the United States, where we honor all the soldiers who have fought and fallen for our country. The peace and prosperity that I have enjoyed my entire life is because of a price paid, many times over, mostly by people…
You and I have lived on planet Earth long enough to know that if you want to launch something into space, it needs to travel fast enough to escape the pull of Earth's gravity. Launch it with too slow of a speed, and it crashes back into Earth. Launch it with a little more speed, and you can send it into orbit (like a satellite). But launch it fast enough, and it can escape from Earth's gravity altogether. The speed to completely escape from Earth's gravity is pretty fast: about 11.2 km/s, or 7 miles per second! Make something denser and more massive, and you'll have to go faster and faster…