Science Daily: Comets and Asteroids

Astrophysicists predict Earth-like planet in star system only 16 light years away

Astrophysicists have predicted that an Earth-like planet may be lurking in a star system just 16 light years away. The team investigated the star system Gliese 832 for additional exoplanets residing between the two currently known alien worlds in this system. Their computations revealed that an additional Earth-like planet with a dynamically stable configuration may be residing at a distance ranging from 0.25 to 2.0 astronomical unit (AU) from the star.

Four Earth-sized planets detected orbiting the nearest sun-like star

Astronomers have discovered four Earth-sized planets orbiting the nearest sun-like star, tau Ceti, which is about 12 light years away and visible to the naked eye. These planets have masses as low as 1.7 Earth mass, making them among the smallest planets ever detected around nearby sun-like stars. Two of them are super-Earths located in the habitable zone of the star, meaning they could support liquid surface water.

NASA Protects its super heroes from space weather

When astronauts travel in space they can't see or even feel radiation. However, NASA's Human Research Program (HRP) is studying the effects radiation plays on the human body and developing ways to monitor and protect against this silent hazard.

Mars 2020 mission to use smart methods to seek signs of past life

NASA's Mars 2020 mission, which will look for signs of past life on Mars, will use smart methods originally developed to find the oldest life on Earth, according the mission's Deputy Project Scientist. The 2020 mission will make coordinated measurements that could detect signs of ancient life - or biosignatures - in their original spatial context. These techniques, known as 'spatially resolved biosignature analysis' derive from geochemical analysis of early life on Earth.

Tracking a solar eruption through the solar system

Ten spacecraft, from ESA's Venus Express to NASA's Voyager-2, felt the effect of a solar eruption as it washed through the solar system while three other satellites watched, providing a unique perspective on this space weather event.

Lunar dynamo's lifetime extended by at least 1 billion years

Astronomers report that a lunar rock collected by NASA's Apollo 15 mission exhibits signs that it formed 1 to 2.5 billion years ago in the presence of a relatively weak magnetic field of about 5 microtesla. That's around 10 times weaker than Earth's current magnetic field but still 1,000 times larger than fields in interplanetary space today.

Successful filming of fastest aurora flickering

Researchers conducted a 3 year continuous high-speed imaging observation at Poker Flat Research Range, Alaska, USA, and identified the physics behind the flickering of aurora. At the same time, they discovered faster flickerings at speeds of 1/60-1/50 and 1/80 of a second.

Chaco Canyon petroglyph may represent ancient total eclipse

As the hullabaloo surrounding the Aug. 21 total eclipse of the sun swells by the day, an expert says a petroglyph in New Mexico's Chaco Canyon may represent a total eclipse that occurred there a thousand years ago.

Astronauts to bring asteroid back into lunar orbit

Future space exploration aims to fly further from Earth than ever before. New research examines the robotic phase of the Asteroid Redirect Mission (ARM). In addition to taking manned spaceflights deeper into space than ever before, the proposed mission would also bring some benefit for planetary science.

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.