Thursday, April 27, 2017

Cassini Dives Between Saturn and Its Rings

This unprocessed image shows features in Saturn's atmosphere from closer than ever before. The view was captured by NASA's Cassini spacecraft during its first Grand Finale dive past the planet on April 26, 2017. Credit: NASA/JPL-Caltech/Space Science Institute

NASA's Cassini spacecraft is back in contact with Earth after its successful first-ever dive through the narrow gap between the planet Saturn and its rings on April 26, 2017. The spacecraft is in the process of beaming back science and engineering data collected during its passage, via NASA's Deep Space Network Goldstone Complex in California's Mojave Desert. The DSN acquired Cassini's signal at 11:56 p.m. PDT on April 26, 2017 (2:56 a.m. EDT on April 27) and data began flowing at 12:01 a.m. PDT (3:01 a.m. EDT) on April 27.

Sun's Eruptions Might All Have Same Trigger

Solar eruptions of many sizes, including enormous coronal mass ejections (pictured), could be triggered by a single process. Credit: NASA/SDO

Large and small scale solar eruptions might all be triggered by a single process, according to new research that leads to better understanding of the Sun's activity. Researchers at Durham University, UK, and NASA's Goddard Space Flight Center, USA, used 3D computer simulations to show a theoretical link between large and small scale eruptions that were previously thought to be driven by different processes.

'Iceball' Planet Discovered Through Microlensing

This artist's concept shows OGLE-2016-BLG-1195Lb, a planet discovered through a technique called microlensing. Credits: NASA/JPL-Caltech

Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists' understanding of the types of planetary systems that exist beyond our own.

Wednesday, April 26, 2017

New Survey Hints at Ancient Origin for the Cold Spot

The map of the cosmic microwave background (CMB) sky produced by the Planck satellite. Red represents slightly warmer regions, and blue slightly cooler regions. The Cold Spot is shown in the inset, with coordinates on the x- and y-axes, and the temperature difference in millionths of a degree in the scale at the bottom. Credit: ESA and Durham University.

A supervoid is unlikely to explain a 'Cold Spot' in the cosmic microwave background, according to the results of a new survey, leaving room for exotic explanations like a collision between universes. The researchers, led by postgraduate student Ruari Mackenzie and Professor Tom Shanks in Durham University's Centre for Extragalactic Astronomy, publish their results in Monthly Notices of the Royal Astronomical Society.

Scientists Discover Lull in Mars’ Giant Impact History

Mars bears the scars of five giant impacts, including the ancient giant Borealis basin (top of globe), Hellas (bottom right), and Argyre (bottom left). An SwRI-led team discovered that Mars experienced a 400-million-year lull in impacts between the formation of Borealis and the younger basins. Image Courtesy of University of Arizona/LPL/Southwest Research Institute

From the earliest days of our solar system’s history, collisions between astronomical objects have shaped the planets and changed the course of their evolution. Studying the early bombardment history of Mars, scientists at Southwest Research Institute (SwRI) and the University of Arizona have discovered a 400-million-year lull in large impacts early in Martian history.

Tuesday, April 25, 2017

Astrophysicists Study the 'Rejuvenating' Pulsar in a Neighboring Galaxy

The slowest spinning X-ray pulsar in a globular star cluster has been discovered in the Andromeda galaxy. This object is a small and very dense neutron star pulling gas from a companion star. Infalling gas forms a bright hot spot on the neutron star surface, which creates a light-house effect, because the neutron star revolves every 1.2 seconds. Credit: Artwork by A. Zolotov

The Lomonosov Moscow State University scientists published the results of a study of the unique ultra-slow pulsar XB091D. This neutron star is believed to have captured a companion only a million years ago and since then, has been slowly restoring its rapid rotation. The young pulsar is located in one of the oldest globular star clusters in the Andromeda galaxy, where the cluster may once have been a dwarf galaxy.

Interdisciplinary Studies Reveal Relationship Between Solar Activity and Climate Change

Solar impacts on earth's climate are most sensitive in polar and tropical Pacific regions and the monsoon activity plays a crucial role in the propagation of solar signal between different latitudes. Credit: Ziniu Xiao

The solar flux is considered the fundamental energy source of earth's climate system on long time scales. In recent decades, some studies have noted that the tiny variations in solar activity could be amplified by the nonlinear process in climate system. Therefore, the astronomy factors, such as solar activity, present intriguing and cutting-edge questions to better understand climate change.