September 21, 2017

The Great Orbiting Observatories II: The Ultraviolet.

Galaxy M81 blazes with star birth in the ultraviolet. (Creidt: GALEX/NASA).

Galaxy M81 blazes with star birth in the ultraviolet. (Credit: GALEX/NASA).

 

   When we last left our installment of this saga, we covered the observatories that target the visible edge of our spectrum. This is a narrow slice; a tiny sliver of what we call the electromagnetic spectrum. This week, we move into the ultraviolet, a span of the spectrum at roughly between 10 to 320 nanometers. UV from space is almost entirely absorbed by our atmosphere, and thus, if you want to observe the universe or do UV astronomy, you have to go into space to do it. [Read more...]

Space Telescopes, Part I: Optical.

 
(Credit: NASA/ESA/S. Gallagher/J. English).
(Credit: NASA/ESA/S. Gallagher/J. English).
 

 Hickson Group 31 of galaxies as imaged by Hubble.

   This weeks’ expose will kick off our four part series on orbiting space telescopes. For starters, we’ll begin with the most familiar; the optical wavelength. True, we as humans are biased towards this narrow band of the spectrum; we love to see pretty pictures that we can relate to.  But beyond this, telescopes that operate in the visual wavelengths have no less than revolutionized astronomy, as well as laid promise for perhaps giving us images of exo-Earths in our lifetimes. What follows is a rapid fire list of what was, is, and what to look for up and coming in the realm of optical astronomy in space: [Read more...]