Category Astronomy/Space

An artist concept depicting one of NASA’s twin Voyager spacecraft. Humanity’s farthest and longest-lived spacecraft are celebrating 40 years in August and September 2017.

A set of  thrusters aboard the Voyager 1 spacecraft successfully fired up Wednesday after 37 years without use. Voyager 1, NASAis farthest and fastest spacecraft, is the only human-made object in interstellar space, the environment between the stars. The spacecraft, which has been flying for 40 years, relies on small devices called thrusters to orient itself so it can communicate with Earth. These thrusters fire in tiny pulses, or “puffs,” lasting mere milliseconds, to subtly rotate the spacecraft so that its antenna points at our planet...

1. Left: The surface of Rosetta’s comet. As the comet approaches the Sun, frozen gases evaporate from below the surface, dragging tiny particles of dust along with them. Right: These dust grains can be captured and examined using the COSIMA instrument. Targets such as this one measuring only a few centimeters act as dust collectors. They retain dust particles of up to 100 microns in size. 2. Left: Overview of the chemical elements that make up Rosetta’s comet. Right: Average mass distribution of organic and mineral substances in Rosetta’s comet.

The dust that comet 67P/Churyumov-Gerasimenko emits into space consists to about one half of organic molecules. The dust belongs to the most pristine and carbon-rich material known in our solar system and has hardly changed since its birth...

Image of starlight on exoplanet. Credit: Courtesy of NASA/JPL-Caltech.

Is there life beyond Earth in the cosmos? Astronomers looking for signs have found that our Milky Way galaxy teems with exoplanets, some with conditions that could be right for extraterrestrial life. Such worlds orbit stars in “habitable zones,” regions where planets could hold liquid water that is necessary for life as we know it. However, the question of habitability is highly complex. Researchers led by space physicist Chuanfei Dong of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University have recently raised doubts about water on – and thus potential habitability of – frequently cited exoplanets that orbit red dwarfs, the most common stars in the Milky Way.

In two ...

Black hole artist’s concept. Credit: © nasa_gallery / Fotolia

A new study outlines how gravitational wave experiments could be used to test the existence of primordial black holes, gravity wells formed just moments after the Big Bang that some scientists have posited could be an explanation for dark matter. “We know very well that black holes can be formed by the collapse of large stars, or as we have seen recently, the merger of two neutron stars,” said Savvas Koushiappas, an associate professor of physics at Brown University and coauthor of the study with Avi Loeb from Harvard University. “But it’s been hypothesized that there could be black holes that formed in the very early universe before stars existed at all. That’s what we’re addressing with this work.”

The idea is that shortly af...