Aug 29
NASA’s Spitzer Telescope Witnesses Asteroid Smashup | NASA
This artist’s concept shows the immediate aftermath of a large asteroid impact around NGC 2547-ID8, a 35-million-year-old sun-like star. NASA’s Spitzer Space Telescope witnessed a giant surge in dust around the star, likely the result of two asteroids colliding.
Image Credit:
NASA/JPL-Caltech
NASA’s Spitzer Space Telescope has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the formation of planets.
Scientists had been regularly tracking the star, called NGC 2547-ID8, when it surged with a huge amount of fresh dust between August 2012 and January 2013.
“We think two big asteroids crashed into each other, creating a huge cloud of grains the size of very fine sand, which are now smashing themselves into smithereens and slowly leaking away from the star,” said lead author and graduate student Huan Meng of the University of Arizona, Tucson.
While dusty aftermaths of suspected asteroid collisions have been observed by Spitzer before, this is the first time scientists have collected data before and after a planetary system smashup. The viewing offers a glimpse into the violent process of making rocky planets like ours.
Rocky planets begin life as dusty material circling around young stars. The material clumps together to form asteroids that ram into each other. Although the asteroids often are destroyed, some grow over time and transform into proto-planets. After about 100 million years, the objects mature into full-grown, terrestrial planets. Our moon is thought to have formed from a giant impact between proto-Earth and a Mars-size object.
via NASA’s Spitzer Telescope Witnesses Asteroid Smashup | NASA.
Aug 26
NASA’s New Horizons Spacecraft Crosses Neptune Orbit En Route to Historic Pluto Encounter | NASA
NASA’s Pluto-bound New Horizons spacecraft captured this view of the giant planet Neptune and its large moon Triton on July 10, 2014, from a distance of about 2.45 billion miles (3.96 billion kilometers) – more than 26 times the distance between the Earth and sun.
Image Credit:
NASA/Johns Hopkins University Applied Physics Laboratory
NASA’s Pluto-bound New Horizons spacecraft has traversed the orbit of Neptune. This is its last major crossing en route to becoming the first probe to make a close encounter with distant Pluto on July 14, 2015.
The sophisticated piano-sized spacecraft, which launched in January 2006, reached Neptune’s orbit — nearly 2.75 billion miles from Earth — in a record eight years and eight months. New Horizons’ milestone matches precisely the 25th anniversary of the historic encounter of NASA’s Voyager 2 spacecraft with Neptune on Aug. 25, 1989.
“It’s a cosmic coincidence that connects one of NASA’s iconic past outer solar system explorers, with our next outer solar system explorer,” said Jim Green, director of NASA’s Planetary Science Division, NASA Headquarters in Washington. “Exactly 25 years ago at Neptune, Voyager 2 delivered our ‘first’ look at an unexplored planet. Now it will be New Horizons’ turn to reveal the unexplored Pluto and its moons in stunning detail next summer on its way into the vast outer reaches of the solar system.”
New Horizons now is about 2.48 billion miles from Neptune — nearly 27 times the distance between the Earth and our sun — as it crosses the giant planet’s orbit at 10:04 p.m. EDT Monday. Although the spacecraft will be much farther from the planet than Voyager 2’s closest approach, New Horizons’ telescopic camera was able to obtain several long-distance “approach” shots of Neptune on July 10.
via NASA’s New Horizons Spacecraft Crosses Neptune Orbit En Route to Historic Pluto Encounter | NASA.
