Category Astronomy/Space

This Hubble Space Telescope image of globular cluster M79 is a combination of observations taken in 1995 and 1997 by Hubble’s Wide Field Planetary Camera 2. The red, green, and blue colors used to compose the image represent a natural view of the cluster. Credit: NASA and ESA; Acknowledgment: S. Djorgovski (Caltech) and F. Ferraro (University of Bologna)

It’s beginning to look a lot like the holiday season in this NASA Hubble Space Telescope image of a blizzard of stars, which resembles a swirling snowstorm in a snow globe. The stars are residents of the globular star cluster Messier 79, or M79, 41,000 light-years from Earth, in the constellation Lepus. The cluster is also known as NGC 1904. Globular clusters are gravitationally bound groupings of as many as 1 million stars...

Low-energy electron impact mediates the creation of new complex organic molecules, such as ethanol, in astrophysical/planetary model ices containing methane and oxygen; while some of the new species desorb as ions, many remain in the surface ices. Credit: The photo of Jupiter’s moon Europa, inserted for the Platinum (Pt) substrate (bottom of the graphic), is credited to NASA.

Where do the molecules required for life originate? A new study shows that a number of small organic molecules can form in a cold, spacelike environment full of radiation. Investigators at the University of Sherbrooke in Canada have created simulated space environments in which thin films of ice containing methane and oxygen are irradiated by electron beams...

Our home Milky Way galaxy (MW, yellow) and our companion Andromeda galaxy (M31, red) are participating in a downward flow away from a vast underdense region called the Local Void and toward the Virgo Cluster, represented by the purple spherecircle. Most galaxies between us and the Virgo Cluster will eventually fall into the cluster but we lie slightly beyond the capture zone. Credit: R. Brent Tully

Researchers have constructed the galaxies’ motions from 13 billion years in the past to the present day. A team of astronomers from Maryland, Hawaii, Israel and France has produced the most detailed map ever of the orbits of galaxies in our extended local neighborhood, showing the past motions of almost 1,400 galaxies within 100 million light years of the Milky Way.

The main gravitational attrac...

Display of the survival of meteoroid with air permeability κ/κ0 = 0.25, until its breakup at an altitude of 32 km.

Our atmosphere is a better shield from meteoroids than researchers thought. When a meteor comes hurtling toward Earth, the high-pressure air in front of it seeps into its pores and cracks, pushing the body of the meteor apart and causing it to explode. “There’s a big gradient between high-pressure air in front of the meteor and the vacuum of air behind it,” said Jay Melosh, a professor of Earth, Atmospheric and Planetary Sciences at Purdue University and co-author of the paper. “If the air can move through the passages in the meteorite, it can easily get inside and blow off pieces.”

Researchers knew that meteoroids often blew up before they reach Earth’s surface, but they di...