A group of unusual giant black holes may be consuming excessive amounts of matter, according to a new study. This finding may help astronomers understand how the largest black holes were able to grow so rapidly in the early Universe.
Io, the innermost of the four moons of Jupiter discovered by Galileo Galilei in 1610 and only slightly bigger than our own moon, is the most geologically active body in our solar system. Hundreds of volcanic areas dot its surface, which is mostly covered with sulfur and sulfur dioxide. The largest of these volcanic features, named Loki after the Norse god often associated with fire and chaos, is a volcanic depression called patera in which the denser lava crust solidifying on top of a lava lake episodically sinks in the lake, yielding a raise in the thermal emission that has been regularly observed from Earth. Loki, only 124 miles in diameter and at least 373 million miles from Earth, was, up until recently, too small to be looked at in detail from any ground-based optical/infrared telescope.
What happens to an astronaut's brain during a mission to Mars? Nothing good. It's besieged by destructive particles that can forever impair cognition, according to a radiation oncology study. Exposure to highly energetic charged particles -- much like those found in the galactic cosmic rays that bombard astronauts during extended spaceflights -- cause significant damage to the central nervous system, resulting in cognitive impairments.
For the first time, images from NASA's New Horizons spacecraft are revealing bright and dark regions on the surface of faraway Pluto -- the primary target of the New Horizons close flyby in mid-July.
A NASA planetary exploration mission came to a planned, but nonetheless dramatic, end April 30 when it slammed into Mercury's surface at about 8,750 mph and created a new crater on the planet's surface.
A team of highly determined high school students discovered a never-before-seen pulsar. Further observations by astronomers using the GBT revealed that this pulsar has the widest orbit of any around a neutron star and is part of only a handful of double neutron star systems.
The discovery of a strange exoplanet orbiting very close to a small cool star 500 light years away is challenging ideas about how planets form.
Astronomers have produced the first complete three-dimensional view of the famous Pillars of Creation in the Eagle Nebula, Messier 16. The new observations demonstrate how the different dusty pillars of this iconic object are distributed in space and reveal many new details. Intense radiation and stellar winds from the cluster's brilliant stars have sculpted the dusty Pillars of Creation over time and should fully evaporate them in about three million years.
Groundbreaking images of the Sun give a first-ever detailed view of the interior structure of umbrae -- the dark patches in the center of sunspots -- revealing dynamic magnetic fields responsible for the plumes of plasma that emerge as bright dots interrupting their darkness.
The sun's surface is blisteringly hot at 10,340 degrees Fahrenheit -- but its atmosphere is another 300 times hotter. This has led to an enduring mystery for those who study the sun: What heats the atmosphere to such extreme temperatures? Normally when you move away from a hot source the environment gets cooler, but some mechanism is clearly at work in the solar atmosphere, the corona, to bring the temperatures up so high.
Messenger's historic mission to the planet Mercury about to end. Also: New clues about the very first stars to shine in the Universe, and a massive magma chamber discovered deep under the Yellowstone supervolcano.
Astronomers discovered a planetary system orbiting a nearby star that is only 54 light-years away. All three planets orbit their star at a distance closer than Mercury orbits the sun, completing their orbits in just five, 15, and 24 days.
Scientists have captured the first high-resolution images of the flaring magnetic structures known as solar flux ropes at their point of origin in the sun's chromosphere.
The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the solar system's innermost planet. MESSENGER's highly successful orbital mission is about to come to an end, as the spacecraft runs out of propellant and the force of solar gravity causes it to impact the surface of Mercury near the end of April 2015.
How soon after the Big Bang could water have existed? Not right away, because water molecules contain oxygen and oxygen had to be formed in the first stars. Then that oxygen had to disperse and unite with hydrogen in significant amounts. New theoretical work finds that despite these complications, water vapor could have been just as abundant in pockets of space a billion years after the Big Bang as it is today.