Category Astronomy/Space

This false-color image, derived from observations in infrared light by the Ralph/Linear Etalon Imaging Spectral Array (LEISA) instrument, shows where the spectral features of water ice are abundant on Pluto’s surface. It is based on two LEISA scans of Pluto obtained on July 14, 2015, from a range of about 67,000 miles (108,000 kilometers). The scans, taken about 15 minutes apart, were stitched into a combined multispectral Pluto “data cube” covering the full hemisphere visible to New Horizons as it flew past Pluto. A data cube like this is a three-dimensional array in which an image of Pluto is formed at each LEISA-sensitive wavelength.

Water ice is Pluto’s crustal “bedrock,” the canvas on which its more volatile ices paint their seasonally changing patterns...

This image shows from left Paul Warren, Edward Young and Issaku Kohl. Young is holding a sample of a rock from the moon. Credit: Christelle Snow/UCLA

The moon was formed from a violent, head-on collision between early Earth and ‘planetary embryo’ called Theia ~100 million years after the Earth formed, almost 4.5 billion years ago. Many thought Earth collided with Theia at 45 degrees or more. New evidence substantially strengthens the case for a head-on assault.

The researchers analyzed seven rocks brought to the Earth from the moon by the Apollo 12, 15 and 17 missions, as well as 6 volcanic rocks from the Earth’s mantle – 5 from Hawaii and 1 from Arizona. The key to reconstructing the giant impact was a chemical signature in the rocks’ O atoms...

This composite image shows the size and location of the Smith Cloud on the sky. The cloud appears in false-color, radio wavelengths as observed by the Robert C. Byrd Green Bank Telescope in West Virginia. The visible-light image of the background star field shows the cloud’s location in the direction of the summer constellation Aquila. The cloud is 15 degrees across in angular size — the width of an outstretched hand at arm’s length. The apparent size of the full moon is added for comparison. Credit: B. Saxton and F. Lockman (NRAO/AUI/NSF), and A. Mellinger

New Hubble telescope observations suggest a high-velocity H gas cloud was launched from the outer regions of our own galaxy around 70 million years ago...

Associate Professor Joan Vaccaro, of Griffith University’s Centre for Quantum Dynamics Credit: Griffith University

New research from Griffith University’s Centre for Quantum Dynamics is broadening perspectives on time and space. A/Prof Joan Vaccaro challenges the long-held presumption that time evolution—the incessant unfolding of the universe over time—is an elemental part of Nature. She suggests there may be a deeper origin due to a difference between the directions of time: to the future and to the past.

“If you want to know where the universe came from and where it’s going, you need to know about time,” says Associate Professor Vaccaro.
“Experiments on subatomic particles over the past 50 years ago show that Nature doesn’t treat both directions of time equally...