Category Astronomy/Space

New Aurorae detected on Jupiter’s Four Largest Moons

Artist’s depiction of oxygen aurora on Jupiter’s moon Ganymede, the largest moon in the solar system, as observed from Maunakea on Hawaiʻi Island using the twin Keck Observatory telescopes. Credit: Julie Inglis

Astronomers using W. M. Keck Observatory on Maunakea in Hawaiʻi have discovered that aurorae at visible wavelengths appear on all 4 major moons of Jupiter: Io, Europa, Ganymede, and Callisto.

Using Keck Observatory’s High-Resolution Echelle Spectrometer (HIRES) as well as high-resolution spectrographs at the Large Binocular Telescope and Apache Point Observatory, a team led by Caltech and Boston University observed the moons in Jupiter’s shadow so that their faint aurorae, which are caused by the gas giant’s strong magnetic field, could be spotted without competition fr...

Read More

Four Classes of Planetary Systems

Artist impression of the four classes of planetary system architecture. A new architecture framework allows researchers to study an entire planetary system at the systems level. If the small planets within a system are close to the star and massive planets further away, such systems have ‘Ordered’ architecture. Conversely, if the mass of the planets in a system tends to decrease with distance to the star these systems are ‘Anti-Ordered’. If all planets in a system have similar masses, then the architecture of this system is ‘Similar’. ‘Mixed’ planetary systems are those in which the planetary masses show large variations. Research suggests that planetary systems which have the same architecture class have common formation pathways...
Read More

Scientists find First Evidence that Black Holes are the Source of Dark Energy

NGC524.jpg
​NGC 524 is a galaxy in the constellation Pisces, and is one of the galaxies observed in this study. It is at a distance of about 90 million light years away from Earth. Credit: ESA/Hubble​

Observations of supermassive black holes at the centers of galaxies point to a likely source of dark energy—the ‘missing’ 70% of the universe.

The measurements from ancient and dormant galaxies show black holes growing more than expected, aligning with a phenomenon predicted in Einstein’s theory of gravity. The result potentially means nothing new has to be added to our picture of the universe to account for dark energy: black holes combined with Einstein’s gravity are the source.

The conclusion was reached by a team of 17 researchers in nine countries, led by the University of Hawai’i a...

Read More

Complex Subsurface of Mars imaged by Chinese Rover Zhurong

Complex subsurface of Mars imaged by Chinese rover Zhurong
A selfie taken by the Zhurong rover alongside its landing platform, captured with a wireless camera. Source: CNSA. Credit: Chinese National Space Administration

Ground-penetrating radar from China’s Martian rover Zhurong reveals shallow impact craters and other geologic structures in the top five meters of the Red Planet’s surface. The images of the Martian subsurface are presented in a paper published in Geology.

The Zhurong rover was sent to Mars as part of China’s Tianwen-1 mission. Launched in July 2020, the rover landed on the surface on 15 May 2021. The rover was sent to a large plain in the northern hemisphere of Mars named Utopia Planitia, near the boundary between the lowlands where it landed and highlands to the south.

The region was chosen because it’s near suspected a...

Read More