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.

Monday, April 24, 2017

New ALICE Experiment Results Show Novel Phenomena in Proton Collisions

© 2017 CERN for the benefit of the ALICE Collaboration

In a paper published today in Nature Physics, the ALICE collaboration reports that proton collisions sometimes present similar patterns to those observed in the collisions of heavy nuclei. This behavior was spotted through observation of so-called strange hadrons in certain proton collisions in which a large number of particles are created.

Cassini, Voyager Missions Suggest New Picture of Sun’s Interaction with Galaxy

New data from NASA’s Cassini, Voyager and Interstellar Boundary Explorer missions show that the heliosphere — the bubble of the sun’s magnetic influence that surrounds the inner solar system — may be much more compact and rounded than previously thought. The image on the left shows a compact model of the heliosphere, supported by this latest data, while the image on the right shows an alternate model with an extended tail. The main difference is the new model’s lack of a trailing, comet-like tail on one side of the heliosphere. This tail is shown in the old model in light blue. Credits: Dialynas, et al. (left); NASA (right)

New data from NASA’s Cassini mission, combined with measurements from the two Voyager spacecraft and NASA’s Interstellar Boundary Explorer, or IBEX, suggests that our sun and planets are surrounded by a giant, rounded system of magnetic field from the sun — calling into question the alternate view of the solar magnetic fields trailing behind the sun in the shape of a long comet tail.

Sunday, April 23, 2017

Holographic Universe: Computing the Cosmological Observables

Sketch of timeline of the holographic universe. Credit Paul McFadden.

In the beginning of 2017, a team of researchers has presented the first observational evidence that our universe could be a hologram. In a paper published Jan. 27 in the journal Physical Review Letters, the scientists described their tests of a class of holographic models for the very early universe against cosmological observations. It now turns out that the most challenging part of this study was to compute the observables and compare them with observations.

S.S. John Glenn OA-7 Cygnus Berthed to ISS

The S.S. John Glenn is moved to its berthing position at the Earth-facing port of the Unity module. Photo Credit: NASA TV

After a four-day cruise to the International Space Station, Orbital ATK’s OA-7 Cygnus spacecraft, named S.S. John Glenn, was captured and berthed to the outpost. Capture of the 21-foot (6.4-meter) long spacecraft by the station’s robotic Canadarm2 came at 6:05 a.m. EDT (10:05 GMT) April 22, 2017. Expedition 51 Flight Engineer Thomas Pesquet of the European Space Agency as well as Commander Peggy Whitson of NASA were at the Robotics Work Station in the Cupola window controlling the arm.

China's Cargo Spacecraft Docks with Space Lab

Photo taken on April 22, 2017 shows the Tianzhou-1 cargo spacecraft moving towards the orbiting Tiangong-2 space lab for the automated docking on a screen at Beijing Aerospace Control Center in Beijing, capital of China. The Tianzhou-1 cargo spacecraft, China's first cargo spacecraft, which was launched Thursday evening from Wenchang Space Launch Center in south China's Hainan Province, successfully completed automated docking with the orbiting Tiangong-2 space lab at 12:23 p.m. Saturday, according to Beijing Aerospace Control Center. It is the first docking between the spacecraft and space lab. (Xinhua/Wang Sijiang)

The Tianzhou-1 cargo spacecraft successfully completed automated docking with the orbiting Tiangong-2 space lab at 12:23 p.m. Saturday, according to Beijing Aerospace Control Center. It is the first docking between the spacecraft and space lab.