Category Astronomy/Space

Spontaneous ‘Dust Traps:’ Astronomers discover a missing link in planet formation

1. Stages of the formation mechanism for dust traps. The central star is depicted as yellow, surrounded by the protoplanetary disk, here shown in blue. The dust grains make up the band running through the disk. In the first stage, the dust grains grown in size, and move inwards towards the central star. The now pebble-sized larger grains (in the second panel) then pile up and slow down, and in the third stage the gas is pushed outwards by the back-reaction, creating regions where dust accumulates, the so-called dust traps. The traps then allow the pebbles to aggregate to form planetesimals, and eventually planet-sized worlds. Credit: © Volker Schurbert. Click for a full size image 2. An image of a protoplanetary disk, made using results from the new model, after the formation of a spontaneous dust trap, visible as a bright dust ring. Gas is depicted in blue and dust in red. Credit: Jean-Francois Gonzalez. Click for a full size image

1. Stages of the formation mechanism for dust traps. The central star is depicted as yellow, surrounded by the protoplanetary disk, here shown in blue. The dust grains make up the band running through the disk. In the first stage, the dust grains grown in size, and move inwards towards the central star. The now pebble-sized larger grains (in the second panel) then pile up and slow down, and in the third stage the gas is pushed outwards by the back-reaction, creating regions where dust accumulates, the so-called dust traps. The traps then allow the pebbles to aggregate to form planetesimals, and eventually planet-sized worlds. Credit: © Volker Schurbert. Click for a full size image
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Preserving Vision for Astronauts

JAXA astronaut Koichi Wakata sits in the chin rest during an Optical Coherence Tomography (OCT) session on ISS.

Credit: NASA JAXA astronaut Koichi Wakata sits in the chin rest during an Optical Coherence Tomography (OCT) session on ISS.

Many astronauts who come back from space experience poorer vision after flight, some even years after, and researchers at the University of Alabama at Birmingham are working to see why. Brian Samuels, M.D., assistant professor in the Department of Ophthalmology, and his fellow collaborators from the Georgia Institute of Technology and Emory University recently received a grant to study computational modeling as a method of determining why astronauts who are in space for extended periods of time are experiencing eye pathologies...

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Volcanic hydrogen spurs chances of finding Exoplanet life

Volcanic hydrogen spurs chances of finding exoplanet life

Ramses M. Ramirez and Lisa Kaltenegger. A Volcanic Hydrogen Habitable Zone. Astrophysical Journal Letters, February 2017 DOI: 10.3847/2041-8213/aa60c8

Hunting for habitable exoplanets now may be easier: Cornell University astronomers report that hydrogen pouring from volcanic sources on planets throughout the universe could improve the chances of locating life in the cosmos. Planets located great distances from stars freeze over. “On frozen planets, any potential life would be buried under layers of ice, which would make it really hard to spot with telescopes,” said Ramses Ramirez, Cornell’s Carl Sagan Institute. “But if the surface is warm enough – thanks to volcanic hydrogen and atmospheric warming – you could have life on the surface, generating a slew of detectable signatures.”

Combini...

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Saturn’s Rings viewed in the Mid-Infrared show bright Cassini Division

1.Comparison of the images of Saturn’s rings in the 2008 view in the mid-infrared (left) and the visible light (right). The visible light image was taken on March 16, 2008 with the 105-cm Murikabushi telescope at Ishigakijima Astronomical Observatory. The radial brightness contrast of Saturn’s rings is the inverse between the two wavelength ranges. (Credit: NAOJ) 2.Comparison of the mid-infrared images of Saturn’s rings on April 30, 2005 (top) and January 23, 2008 (bottom). Although both of the images were taken in the mid-infrared, the radial contrast of Saturn’s rings is the inverse of each other. (Credit: NAOJ) 3. A three-color composite of the mid-infrared images of Saturn on January 23, 2008 captured with COMICS on the Subaru Telescope...

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