Daily Archives: July 9, 2014

Gliese 832c: The Closest Potentially Habitable Exoplanet 


Image Credit & Copyright: The Planetary Habitability Laboratory @ UPR Arecibo;
Discovery: Robert A. Wittenmyer (UNSW Australia) et al.

 This planet is only 16 light years away – could it harbor life? Recently discovered exoplanet Gliese 832c has been found in a close orbit around a star that is less bright than our Sun. An interesting coincidence, however, is that Gliese 832c receives just about the same average energy from its parent star as does the Earth. Since the planet was discovered only by a slight wobble in its parent star’s motion, the above illustration is just an artistic guess of the planet’s appearance – much remains unknown about Gliese 832c’s true mass, size, and atmosphere. If Gliese 832c has an atmosphere like Earth, it may be a super-Earth undergoing strong seasons but capable of supporting life. Alternatively, if Gliese 832c has a thick atmosphere like Venus, it may be a super-Venus and so unlikely to support life as we know it. The close 16-light year distance makes the Gliese 832 planetary system currently the nearest to Earth that could potentially support life. The proximity of the Gliese 832 system therefore lends itself to more detailed future examination and, in the most spectacularly optimistic scenario, actual communication – were intelligent life found there.

APOD NASA 09-Jul-14

Horsehead Nebula IC 434


The Horsehead Nebula (also known as Barnard 33 in emission nebula IC 434) is a dark nebula in the constellation Orion. The nebula is located just to the south of the star Alnitak, which is farthest east on Orion’s Belt, and is part of the much larger Orion Molecular Cloud Complex. The nebula was first recorded in 1888 by Scottish astronomer Williamina Fleming on photographic plate B2312 taken at the Harvard College Observatory. The Horsehead Nebula is approximately 1500 light years from Earth. It is one of the most identifiable nebulae because of the shape of its swirling cloud of dark dust and gases, which bears some resemblance to ahorse’s head when viewed from Earth.

The dark cloud of dust and gas is a region in the Orion Nebula where star formation is taking place. This stellar nursery, as it is known, can contain over 100 known organic and inorganic gases as well as dust consisting of large and complex organic molecules.

The red or pinkish glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. Magnetic fields channel the gases leaving the nebula into streams, shown as streaks in the background glow. A glowing strip of hydrogen gas marks the edge of the massive cloud and the densities of stars are noticeably different on either side.

The heavy concentrations of dust in the Horsehead Nebula region and neighbouring Orion Nebula are localized, resulting in alternating sections of nearly complete opacity and transparency. The darkness of the Horsehead is caused mostly by thick dust blocking the light of stars behind it. The lower part of the Horsehead’s neck casts a shadow to the left. The visible dark nebula emerging from the gaseous complex is an active site of the formation of “low-mass” stars. Bright spots in the Horsehead Nebula’s base are young stars just in the process of forming.

Imaging telescopes or lenses: Sky-Watcher Newton 8″
Imaging cameras: Canon EOS 550D / Rebel T2i
Mounts: Sky-Watcher HEQ5
Focal reducers: Sky-Watcher Coma corrector
Software: DeepSkyStacker, PHD guiding, photoshop
Dates: Oct. 20, 2012
Frames: 20×600″
Integration: 3.3 hours

Author: Ivan Jevremovic
AstroPhotography of the day by SPONLI 09 July 2014