Researchers have conducted a remote reconnaissance of a distant solar system with a new telescope imaging system that sifts through the blinding light of stars. Using a suite of high-tech instrumentation and software called Project 1640, the scientists collected the first chemical fingerprints, or spectra, of this system’s four red exoplanets, which orbit a star 128 light years away from Earth.
The image at the top of the page shows a giant planet orbiting HR 8799. Christian Marois (Herzberg Institute of Astrophysics) and colleagues discovered the fourth giant planet, 'e' in the above image, which lies inwards of planets b,c,d. This is typical when using imaging to hunt for extra-solar planets, since it is the closer-in planets that are harder to find, due to obscuration by the bright central star.
A simulated star was actually removed from this image; the fuzzy blob seen in the center is due to imperfections in this star-subtraction process. These planets lie about 15 to 70 AU away from the central star, and have masses of ~5 to 10 Jupiter masses. So this is a jumbo planetary system, since the orbits and masses are several times larger than that the Solar System's.
The video below shows the long exposure of the HR 8799 system. The star is at the center of the image, blocked by the coronagraph. Each frame of this movie shows a slightly longer wavelength of light, or color progressing through 30 different wavelengths from 1.0 mm to 1.75 mm in the “near infrared,” colors too red for the human eye to see.
The speckles move radially outward from the star because they are an optical effect. Because they move in the movie, and real celestial objects do not change position at different colors on the sky, the planets around this star can be found using software that looks for objects that do not move in this movie.*
The Daily Galaxy via http://www.amnh.org