Category Astronomy/Space

A simulation of the cosmic web, or diffuse tendrils of gas connecting galaxies across the universe. Credit: NASA, ESA, E. Hallman (CU Boulder); Nicastro et al. Observations of the missing baryons in the warm–hot intergalactic medium. Nature, 2018; 558 (7710): 406 DOI: 10.1038/s41586-018-0204-1

Researchers at the University of Colorado Boulder have helped to find the last reservoir of ordinary matter hiding in the universe. Ordinary matter, or “baryons,” make up all physical objects in existence, from stars to the cores of black holes. But until now, astrophysicists had only been able to locate about two-thirds of the matter that theorists predict was created by the Big Bang.

In the new research, an international team pinned down the missing third, finding it in the space between galaxies...



An isolated hill in the Medusae Fossae Formation. The effect of wind erosion on this hill is evident by its streamlined shape. Credit: High Resolution Stereo Camera/European Space Agency.

Explosive volcanic eruptions that shot jets of hot ash, rock and gas skyward are the likely source of a mysterious Martian rock formation, a new study finds. The new finding could add to scientists’ understanding of Mars’s interior and its past potential for habitability, according to the study’s authors.

The Medusae Fossae Formation is a massive, unusual deposit of soft rock near Mars’s equator, with undulating hills and abrupt mesas. Scientists first observed the Medusae Fossae with NASA’s Mariner spacecraft in the 1960s but were perplexed as to how it formed...

This image shows data from NASA/ESA’s Hubble Space Telescope (yellow-white) and NASA’s Chandra X-ray Observatory (purple). The purple-white source in the lower left shows X-ray emission from the remains of a star that was ripped apart as it fell towards an intermediate mass black hole. The host galaxy of the black hole is located in the middle of the image. Credit: X-ray: NASA/CXC/UNH/D.Lin et al, Optical: NASA/ESA/STScI

Scientists have been able to prove the existence of small black holes and those that are super-massive but the existence of an elusive type of black hole, known as intermediate-mass black holes (IMBHs) is hotly debated...

An artist’s impression of what an active galactic nucleus might look like close up. The accretion disk produces the brilliant light in the center. The broad-line region is just above the accretion disk and lost in the glare. Dust clouds are being driven upward by the intense radiation. Credit: Peter Z. Harrington

Mysterious features seen in light emitted from active galactic nuclei may be due to partial obscuration by dust clouds. Many large galaxies have a bright central region called an active galactic nucleus (AGN), powered by matter spiraling into a supermassive black hole...