Astronomy Cast

Our next visit in this tour through the electromagnetic spectrum is the ultraviolet. You can't see it, but anyone who's spent a day out in the hot sun without sunblock has sure experienced its effects. Ultraviolet radiation is associated with the birth of stars and some of the hottest places in the Universe.

Ep. 134: Ultraviolet Astronomy

Optical astronomy; now this is the kind of astronomy a human being was born to do. In fact, until the last century, this was the only kind of astronomy anybody ever did. Now we've got the whole electromagnetic spectrum to explore, but our heart still belongs to optical astronomy. Of course, with bigger telescopes, better optics and more sensitive detectors, even optical astronomy has come a long way.

Ep. 133: Optical Astronomy

If there was enough mass to cause a big crunch, would inflation go backwards too? How do spacecraft know that hydrogen is bonded to water? And why can't we see everything that's ever fallen into a black hole? If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show. Please include your location and a way to pronounce your name.

Questions Show: Undoing Inflation, Searching for Water, and Seeing Everything a Black Hole's Ever Eaten

Today we continue our unofficial tour through the electromagnetic spectrum, stopping at the infrared spectrum - you feel it as heat. This section of the spectrum gives us our only clear view through dusty material to see newly forming planetary systems and shrouded supermassive black holes. And infrared lets us look out to the most distant regions of the observable universe, when the first building blocks of galaxies came together.

Ep. 132: Infrared Astronomy

Last week we examined the largest wavelength in the electromagnetic spectrum: radio. This week we get a little smaller… but not too small! And look at the next step in the spectrum, the submillimeter. Astronomers have only recently began exploiting this tiny slice of the spectrum, but the payoff has been huge.

Ep. 131: Submillimeter Astronomy

This week we wonder if you can made a black hole by accelerating a mass, but then can you un-make it again? Will the Earth ever be tidally locked to the Sun? And can dark matter crush an unsuspecting space ship? If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show. Please include your location and a way to pronounce your name.

Questions Show: Decelerating Black Holes, Earth-Sun Tidal Lock, and the Crushing Gravity of Dark Matter

Astronomers are very resourceful, when it comes to light, they use the whole spectrum - from radio to gamma rays. We see in visible light, but that's just a tiny portion of the spectrum. Today we're going to celebrate the other end of the spectrum; the radio end, where photons really stretch out their wavelengths.

Ep. 130: Radio Astronomy

This week we wonder if the Universe is going to collapse and then expand again, how satellites can have such different velocities, and the size of the observable Universe. If you've got a question for the Astronomy Cast team, please email it in to info@astronomycast.com and we'll try to tackle it for a future show. Please include your location and a way to pronounce your name.