Extinct lunar magnetic field lasted longer than previously thought

Magnetized lunar rocks collected by the Apollo missions indicate the moon had its own magnetic field, generated by motion of liquid metal in its core, until at least 3.2 billion years ago. However, what powered the lunar field and how long it lasted has been unclear. Now, new research reveals that the lunar magnetic field lasted until at least 2.5 billion years ago, and possibly even until 1 billion years ago.

17 Nov 2017

Second stars can distort planet size estimates

When light from a star is blocked by another celestial body — as when the moon obstructed light from the much-larger sun during the recent solar eclipse — astronomers can estimate the density of exoplanets that orbit the star. And from the density, they can determine whether a planet is rocky like Earth or gaseous like Jupiter. But a new study in the Astronomical Journal shows that such density assessments, which are normally calculated from the size of the planet, may be skewed by the presence of “hidden” stars.

08 Nov 2017

Two-faced space worm could inform regenerative medicine

It sounds like the plot of a science fiction movie: Worms sent into space return to Earth with two heads. But it isn’t fiction at all. In a recent study, researchers sent worms with regenerative capabilities — some left whole and some cut into pieces — to the International Space Station (ISS) to study how the worms’ bodies would respond in space and whether their behavior might help efforts to treat human ailments.

19 Oct 2017

Red Planet Roundup: October 2017

With two rovers patrolling the surface of Mars, six spacecraft orbiting above it, and scientists here on Earth studying the Red Planet from afar, new findings are announced often. Here are a few of the latest updates.

13 Oct 2017

Cassini's legacy after two decades

Scientists on Earth have received the last submission from the Cassini spacecraft. It descended into Saturn’s atmosphere at 122,500 kilometers per hour, which caused it to melt, thereby ensuring that Saturn’s moons Titan and Enceladus would remain protected from possible contamination by any errant Earth microbes. Cassini scientists had considered other options for the spacecraft’s end, including leaving it to float endlessly in space or parking it in orbit around Saturn. But ultimately, they chose to have it descend into Saturn’s atmosphere after deciding the data that could be returned from the descent were more valuable than any further data it might obtain by remaining in space. Scientists will make discoveries from these data for decades to come.

15 Sep 2017

Mars class of 2020: A diverse group of missions takes aim at the Red Planet

As many as six missions to Mars might launch in summer 2020, representing a growing and increasingly diverse interest in interplanetary space exploration.
15 Sep 2017

A great time to land on Mars

The 2020 window represents an especially good opportunity for missions looking to reach the Martian surface because of favorable environmental conditions on the planet early in 2021 when the spacecraft will arrive. The elliptical shape of Mars’ orbit means that the planet is, at times, much closer to or farther from the sun, so the amount of sunlight hitting the planet varies dramatically through the Martian year. Meanwhile, the tilt of Mars’ axis, as on Earth, leads to a progression of seasons as the orientations of the northern and southern hemispheres with respect to the sun change regularly and oppositely. The combination of Mars’ orbit and tilt drives an annual cycle of swings in atmospheric pressure of up to about 25 percent as carbon dioxide freezes out of, or sublimes into, the atmosphere.

15 Sep 2017

Making oxygen with MOXIE

The MOXIE (Mars OXygen In-situ resource utilization Experiment) instrument on NASA’s 2020 rover is designed to demonstrate technology that can generate oxygen from carbon dioxide in the Martian atmosphere. Scaled-up versions of the technology could one day be used to produce the large amounts of fuel needed to boost rockets back off the planet’s surface, as well as to create breathing oxygen for human settlements.

15 Sep 2017

Geomedia: Books: Exploring space is risky business

Space is deadly, and the explorers who risk their lives to venture farther into these depths rank among the bravest heroes of all time. In “Mankind Beyond Earth: The History, Science, and Future of Human Space Exploration,” Claude A. Piantadosi portrays the history and future of space exploration through the lens of space medicine, which reminds us of the many threats to the human body that await as we venture away from our planet.

30 Aug 2017

Why meteors snap, crackle and pop

Keen-eared observers sometimes report hearing popping, whistling or buzzing at the same time they see meteors pass far overhead, a perplexing phenomenon called the electrophonic effect. What causes the effect — or if it’s even real — has been discussed for centuries; famed astronomer Edmond Halley is said to have dismissed it as a figment of people’s imaginations. In a new study in Geophysical Research Letters, researchers suggest that not only is it real, but that it is caused by radio waves induced by meteors and converted to sound waves near Earth’s surface.

17 Aug 2017