Most of the cosmic rays arriving at Earth from our galaxy come from nearby clusters of massive stars, according to new observations from NASA’s Advanced Composition Explorer (ACE) spacecraft. But the detection of a few radioactive cosmic-ray iron nuclei also indicates that there has been a supernova in our galactic neighbourhood within the last few million years.
“X” marks the spot of some intriguing surface activity in the latest picture of Pluto returned from NASA’s New Horizons spacecraft. This image from the Long Range Reconnaissance Imager (LORRI) extends New Horizons’ highest-resolution views of Pluto to the very centre of Sputnik Planum, the informally named icy plain that forms the left side of Pluto’s “heart” feature.
Astronomers believe that the Earth-Moon system was created in a giant impact 4.5 billion years ago. Southwest Research Institute scientists combined dynamical, thermal, and chemical models of the Moon’s formation to explain the relative lack of volatile elements like potassium, sodium, and zinc in lunar rocks, when compared to those of Earth.
In September, the New Horizons team released a stunning but incomplete image of Pluto’s crescent. Thanks to updated processing work by the science team, New Horizons is releasing the entire, breathtaking image of Pluto. The team also released images showing extended mapping of the dwarf planet’s “heart” feature and young craters on Pluto’s largest moon, Charon.
New close-up images of Pluto from NASA’s New Horizons spacecraft reveal a bewildering variety of surface features that have scientists reeling because of their range and complexity. Images downlinked in the past few days reveal new features as diverse as possible dunes, nitrogen ice flows oozing out of mountainous regions onto plains, and even networks of valleys possibly carved by material flowing over Pluto’s surface.
NASA’s New Horizons mission has found evidence of exotic ices flowing across Pluto’s surface, at the left edge of its bright heart-shaped area. New close-up images from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) reveal signs of recent geologic activity, something scientists hoped to find but didn’t expect.