September 21, 2017

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...]

23.9.9 CoRoT-7b: A Rare Earth.

Not a prime vacation spot! (Credit: Artist's Impression/ESA).

Not a prime vacation spot! (Credit: Artist's Impression/ESA).

The “Super-Earths” are getting smaller. Recently, the ESA announced that an exoplanet discovered on February 3rd of this year by the CoRoT (Convection Rotation and planetary Transit) satellite is one of the lightest yet… at about five Earth masses, this transiting exoplanet is about twice the diameter of the Earth. But don’t pack your bags just yet; CoRoT-7b as its designated, also zips around its host star every 20.4 hours at a distance 23 times closer than Mercury! This bakes the rocky world with temps in excess of 2000 degrees Celsius. The parent star itself is slighter cooler and younger than our Sun. Follow up measurements by HARPS, the ground based High Accuracy Radial velocity planet Searcher spectrograph at the La Silla Observatory in Chile helped tease out the radial speed and yielded an unexpected bonus; another Earth-like world, CoRoT-7c, which orbits at a relatively sedate 3 days and 17 hours and is 8 times the mass of the Earth. Such bizzare systems may become the norm in the coming years, as exoplanet detection technology becomes more sensitive. The CoRoT-7 system is located about 500 light years away in the plane of the Milky Way galaxy in the constellation Monoceros.