Science Daily: Comets and Asteroids

Primordial asteroids discovered

Astronomers recently discovered a relatively unpopulated region of the main asteroid belt, where the few asteroids present are likely pristine relics from early in solar system history. The team used a new search technique that also identified the oldest known asteroid family, which extends throughout the inner region of the main asteroid belt.

Our solar system's 'shocking' origin story

According to one longstanding theory, our Solar System's formation was triggered by a shock wave from an exploding supernova. It injected material from the exploding star into a neighboring cloud of dust and gas, causing it to collapse in on itself and form the Sun and its surrounding planets. New work offers fresh evidence supporting this theory, modeling the Solar System's formation beyond the initial cloud collapse and into the intermediate stages of star formation.

Defunct satellites: Reliably determine and predict attitude motion

Uncontrollable flying objects in the Earth‘s orbit are an enormous risk for active satellites and for spacecraft in general. Since April 2012, the European environmental satellite ENVISAT has also been adrift in orbit. Now, experts have developed pioneering methods to precisely determine the attitude rotation of malfunctioning satellites and, thus, to support de-orbiting missions in the future.

NASA continues to study pulsars, 50 years after their chance discovery

These rotating 'lighthouse' neutron stars begin their lives as stars between about seven and 20 times the mass of our sun. Some are found to spin hundreds of times per second, faster than the blades of a household blender, and they possess enormously strong magnetic fields.

Earth-like atmosphere may not survive Proxima b's orbit

An Earth-like planet outside the solar system may not be able to keep a grip on its atmosphere, leaving the surface exposed to harmful stellar radiation and reducing its potential for habitability.

Aalto-1 satellite sends first image

The photograph was taken with the VTT Technical Research Centre of Finland developed hyperspectral camera's secondary camera.

Complex chemistry in Saturn's moon Titan's atmosphere

Saturn’s frigid moon Titan has a curious atmosphere. In addition to a hazy mixture of nitrogen and hydrocarbons, like methane and ethane, Titan’s atmosphere also contains an array of more complex organic molecules, including vinyl cyanide, which astronomers recently uncovered in archival ALMA data. Under the right conditions, like those found on the surface of Titan, vinyl cyanide may naturally coalesce into microscopic spheres resembling cell membranes.

Large, distant comets more common than previously thought

There are about seven times more long-period comets measuring at least 1 kilometer across than previously predicted, suggests new research. The researchers also found that long-period comets are, on average, nearly twice as large as 'Jupiter family' comets, whose orbits are shaped by Jupiter's gravity and have periods of less than 20 years.

Moon has a water-rich interior

Using satellite data, researchers have for the first time detected widespread water within ancient explosive volcanic deposits on the moon, suggesting that its interior contains substantial amounts of indigenous water.

NASA looks to solar eclipse to help understand Earth's energy system

It was midafternoon, but it was dark in an area in Boulder, Colorado on Aug. 3, 1998. A thick cloud appeared overhead and dimmed the land below for more than 30 minutes. Well-calibrated radiometers showed that there were very low levels of light reaching the ground, sufficiently low that researchers decided to simulate this interesting event with computer models. Now in 2017, inspired by the event in Boulder, NASA scientists will explore the moon's eclipse of the sun to learn more about Earth's energy system.

Viewing Martian moon orbiting the red planet

While photographing Mars, NASA's Hubble Space Telescope captured a cameo appearance of the tiny moon Phobos on its trek around the Red Planet. Hubble took 13 separate exposures over 22 minutes to create a time-lapse video showing the moon's orbital path.

Ancient, massive asteroid impact could explain Martian geological mysteries

A colossal impact with a large asteroid early in Mars' history may have ripped off a chunk of the northern hemisphere and left behind a legacy of metallic elements in the planet's interior. The crash also created a ring of rocky debris around Mars that may have later clumped together to form its moons, Phobos and Deimos.

Planet Nine hypothesis supported by new evidence

Last year, the existence of an unknown planet in our Solar system was announced. However, this hypothesis was subsequently called into question as biases in the observational data were detected. Now astronomers have used a novel technique to analyze the orbits of the so-called extreme trans-Neptunian objects and, once again, they point out that there is something perturbing them: a planet located at a distance between 300 to 400 times the Earth-Sun separation.

Smallest-ever star discovered by astronomers

The smallest star yet measured has been discovered by a team of astronomers. With a size just a sliver larger than that of Saturn, the gravitational pull at its stellar surface is about 300 times stronger than what humans feel on Earth.

Alien ice on Earth

A flash of green laser followed by pulses of X-rays, and mere nanoseconds later an extraterrestrial form of ice has formed. The miniature crystal reveals how water solidifies under high pressures, like those expected in icy comets, moons and planets.

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