Category Astronomy/Space

All seven planets discovered in orbit around the red dwarf star TRAPPIST-1 could easily fit inside the orbit of Mercury, the innermost planet of our solar system. Credit: NASA/JPL- Caltech

To determine the composition of the TRAPPIST-1 planets, the team used a unique software package that uses state-of-the-art mineral physics calculators. The software, called ExoPlex, allowed the team to combine all of the available information about the TRAPPIST-1 system, including the chemical makeup of the star, rather than being limited to just the mass and radius of individual planets.

TRAPPIST-1 is an ultra-cool red dwarf star that is slightly larger, but much more massive, than the planet Jupiter, located about 40 light-years from the Sun in the constellation Aquarius...

This is an artist’s impression of ‘Oumuamua. Credit: ESO / M. Kornmesser

New research finds that ‘Oumuamua, the rocky object identified as the first confirmed interstellar asteroid, very likely came from a binary star system. “It’s remarkable that we’ve now seen for the first time a physical object from outside our Solar System,” says lead author Dr Alan Jackson, a postdoc at the Centre for Planetary Sciences at the University of Toronto Scarborough in Ontario, Canada. A binary star system, unlike our Sun, is one with two stars orbiting a common centre.

For the new study, published in the journal Monthly Notices of the Royal Astronomical Society, Jackson and his co-authors set about testing how efficient binary star systems are at ejecting objects...

This is a composite which combines gas temperature (as the color) and shock mach number (as the brightness). Red indicates 10 million Kelvin gas at the centers of massive galaxy clusters, while bright structures show diffuse gas from the intergalactic medium shock heating at the boundary between cosmic voids and filaments. Credit: Illustris Team

A multi-institutional team gives the cosmology community a world-class simulation to study how the universe formed. Humans have long tried to explain how stars came to light up the night sky. The wide array of theories throughout history have one common (and correct) governing principle that astrophysicists still use to this day: by understanding the stars and their origins, we learn more about where we come from...

The early ocean known as Arabia (left, blue) would have looked like this when it formed 4 billion years ago on Mars, while the Deuteronilus ocean, about 3.6 billion years old, had a smaller shoreline. Both coexisted with the massive volcanic province Tharsis, located on the unseen side of the planet, which may have helped support the existence of liquid water. The water is now gone, perhaps frozen underground and partially lost to space, while the ancient seabed is known as the northern plains. Robert Citron images, UC Berkeley.

A new scenario seeking to explain how Mars’ putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million years earlier and were not as deep as once thought...