Heavens

A collaboration between researchers in Japan, the USA, and Russia has found a hot spot in Earth's radiation belt where killer electrons, which can cause serious anomalies in satellites, form. The finding, published in the journal Geophysical Research Letters, could help scientists more accurately forecast when these killer (relativistic) electrons will form.

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft has allowed researchers to map the winds that blow high above the red planet's surface, reports a new study, which measures the global circulation of Mars' upper atmosphere for the first time. The results inform our understanding of how Mars lost most of its ancient atmosphere and provide a useful comparison for understanding Earth's upper atmosphere.

A project lead by an international team of researchers use publicly available data with images of the sky dating as far back as to the 1950s to try to detect and analyse objects that have disappeared over time. In the project "Vanishing & Appearing Sources during a Century of Observations" (VASCO), they have particularly looked for objects that may have existed in old military sky catalogues from the 1950s, not to be found again in modern sky surveys. Among the physical indicators that they are looking for are stars that have vanished in the Milky Way.

Astrophysicists are redrawing the textbook image of pulsars, the dense, whirling remains of exploded stars, thanks to NASA's Neutron star Interior Composition Explorer (NICER), an X-ray telescope aboard the International Space Station. Using NICER data, scientists have obtained the first precise and dependable measurements of both a pulsar's size and its mass, as well as the first-ever map of hot spots on its surface.

A new image from NASA's Hubble Space Telescope provides important new details about the first interstellar comet astronomers have seen in our solar system.

The comet, called Comet 2I/Borisov (the "I" stands for interstellar), was spotted near a spiral galaxy known as 2MASX J10500165-0152029. It was approximately 203 million miles from Earth when the image was taken on Nov. 16.

"Everything is determined by forces over which we have no control... Human beings, vegetables, or cosmic dust, we all dance to a mysterious tune, intoned in the distance by an invisible piper." -- Albert Einstein

The NASA/ESA Hubble Space Telescope has once again captured comet 2I/Borisov streaking through our solar system on its way back into interstellar space. At a breathtaking speed of over 175 000 kilometres per hour, Borisov is one of the fastest comets ever seen. It is only the second interstellar object known to have passed through the Solar System.

Nearly a year and a half into its mission, Parker Solar Probe has returned gigabytes of data on the Sun and its atmosphere. Following the release of the very first science from the mission, five researchers presented additional new findings from Parker Solar Probe at the fall meeting of the American Geophysical Union on Dec. 11, 2019.

The most extensive survey of atmospheric chemical compositions of exoplanets to date has revealed trends that challenge current theories of planet formation and has implications for the search for water in the solar system and beyond.

Hydrogen is the most abundant element in the universe and it plays important roles in the structure, dynamics, and evolution of the planets. Hydrogen is transported into deep mantle regions as a hydrous mineral via the subduction of oceanic plates. To better understand the global hydrogen circulation in the Earth's mantle, a number of high-pressure experiments were conducted on the stability of hydrous phases under lower mantle conditions.

Saturn's tiny, frozen moon Enceladus is a strange place. Just 300 miles across, the moon is thought to have an outer shell of ice covering a global ocean 20 miles deep, encasing a rocky core. Slashed across Enceladus' south pole are four straight, parallel fissures or "tiger stripes" from which water erupts. These fissures aren't quite like anything else in the Solar System.

Researchers from the National Astronomical Observatories of the Chinese Academy of Science (NAOC), Peking University and Tsinghua University have found a special population of dwarf galaxies that could mainly consist baryons within radii of up to tens of thousands of light-years. This contrasts with the normal expectation that such regions should instead be dominated by dark matter.

Scientists from Moscow Institute for Physics and Technology, Space Research Institute of the Russian Academy of Sciences (IKI), and Pulkovo Observatory discovered a unique neutron star, the magnetic field of which is apparent only when the star is seen under a certain angle relative to the observer. Previously, all neutron stars could be grouped into two big families: the first one included objects where the magnetic field manifests itself during the whole spin cycle, and the other one included objects where the magnetic field is not measured at all.

Ensuring research opportunities for indigenous, disabled and LGBTQ astronomers is essential if Australian research is to succeed in the new era of "mega-telescopes", a major analysis has found.

In a paper published in the journal Nature Astronomy, Professor Lisa Kewley, director of the ARC Centre of Excellence in All Sky Astrophysics (ASTRO 3D), finds that encouraging astronomers from marginalised communities will increase the chances of significant research discoveries.

A year ago, NASA's Parker Solar Probe flew closer to the sun than any satellite in history, collecting a spectacular trove of data from the very edge of the sun's million-degree corona.

Now, that data has allowed solar physicists to map the source of a major component of the solar wind that continually peppers Earth's atmosphere, while revealing strange magnetic field reversals that could be accelerating these particles toward our planet.