Here is this weeks Video
Jul 13
First Distant Planet to Be Seen in Color Is Blue: Scientific American
BLUE GAS GIANT By observing exoplanet HD 189733 b before, during and after it disappeared behind its host star, astronomers were able to discover that its colour is a deep blue.Image: Artist’s impression
From Nature magazine
A navy-blue world orbiting a faraway star is the first exoplanet to have its colour directly measured.
Discovered in 2005, HD 189733 b is one of the best-studied planets outside the Solar System, orbiting a star about 19 parsecs away in the Vulpecula, or Fox, constellation. Previous efforts to observe the planet focused on the infrared light it emits — invisible to the human eye.
Last December, astrophysicist Tom Evans at the University of Oxford, UK, and his colleagues used the Hubble Space Telescope to observe the planet and its host star. Hubble’s optical resolution is not high enough to actually ‘see’ the planet as a dot of light separate from its star, so instead, the telescope receives light from both objects that mix into a single point source. To isolate the light contribution of the planet, Evans and his colleagues waited for the planet to move behind the star during its orbit, so that its light would be blocked, and looked for changes in light colour.
via First Distant Planet to Be Seen in Color Is Blue [Video]: Scientific American.
Jul 12
Pixelated Moon: Pluto-Bound Spacecraft Gets First View of Charon: Scientific American Gallery
image:NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
NASA’s New Horizons spacecraft, now en route to Pluto, got its first glimpse of the dwarf planet’s largest moon, Charon, in this image released July 10.
Pluto is the bright spot in the center of the image. Charon is the faint smudge up and to the left. New Horizons snapped the picture at about 900 million kilometers from Pluto—six times the distance between Earth and the sun. At that distance, the light from Charon and Pluto takes about 48 minutes to reach New Horizons’s cameras. Charon is roughly the size of Texas, but to the approaching craft it appears no wider than a U.S. quarter seen from 17 kilometers away
Until 2005 Charon was Pluto’s only known moon. Since then astronomers using the Hubble Space Telescope have discovered four more: Nix, Hydra, Kerberos and Styx. Kerberos and Styx are the smallest, each only about a dozen kilometers across; they received their official names just last week.
via Pixelated Moon: Pluto-Bound Spacecraft Gets First View of Charon: Scientific American Gallery.