Flight Dynamics data from THEMIS-B (one of the two ARTEMIS spacecraft) indicated that one of the EFI (electric field instrument)spherical tip masses may have been struck by a meteoroid at 0605 UT on October 14. All science instruments continue to collect data. The probe and science instruments aboard the spacecraft continue to operate nominally. The upcoming insertion into Lissajous orbit will not be interrupted. ARTEMIS stands for “Acceleration, Reconnection, Turbulence and Electrodynamics of...

The lunar rocks brought back to the Earth by the Apollo astronauts were found to have very little water, and to be much drier than rocks on Earth. An explanation for this was that the Moon formed billions of years ago in the solar system's turbulent youth, when a Mars-sized planet crashed into Earth. The impact stripped away our planet's outer layer, sending it into orbit. The pieces later coalesced under their own gravity to form our Moon. Heat from all this mayhem vaporized most of the water...

Pyrocumulonimbus is the fire-breathing dragon of clouds. A cumulonimbus without the "pyre" part is imposing enough -- a massive, anvil-shaped tower of power reaching five miles (8 km) high, hurling thunderbolts, wind and rain. Add smoke and fire to the mix and you have pyrocumulonimbus, an explosive storm cloud actually created by the smoke and heat from fire, and which can ravage tens of thousands of acres. And in the process, "pyroCb" storms funnel their smoke like a chimney into Earth's stratosphere,...

The most famous of all comets, Comet Halley is noted for producing spectacular displays when it passes near Earth on its 76-year trip around the sun. However, you don't have to wait until 2061 to see a piece of the comet -- you can do it this very week! Halley's Comet leaves bits of itself behind -- in the form of small conglomerates of dust and ice called meteoroids -- as it moves in its orbit, which the Earth approaches in early May and mid-October. When it does, it collides with these bits...

View larger On Saturday, October 16, NASA’s Solar Dynamics Observatory captured this stunning image of one of the most intense, solar flares seen in the past few months. So far there have been no reports of energetic particles from this M-class flare interfering with NASA spacecraft or making their way to Earth. Fast-growing sunspot 1112 is crackling with solar flares. The three strongest of this 24 hour period: an M3-flare at 1910 UT on Oct. 16th, a C1-flare at 0900 UT and another C1-flare at...

Observations with NASA’s Chandra, Swift and Rossi X-ray observatories, Fermi Gamma-ray Space Telescope and ESA’s XMM-Newton have revealed that a slowly rotating neutron star with an ordinary surface magnetic field is giving off bursts of X-rays and gamma rays. This discovery may indicate the presence of an internal magnetic field much more intense than the surface magnetic field, with implications for how the most powerful magnets in the cosmos evolve. The neutron star, SGR 0418+5729, was discovered...

NASA's Hubble Space Telescope has captured the first snapshots of a suspected asteroid collision. The images show a bizarre X-shaped object at the head of a comet-like trail of material. In January, astronomers began using Hubble to track the object for five months. They thought they had witnessed a fresh asteroid collision, but were surprised to learn the collision occurred in early 2009. "We expected the debris field to expand dramatically, like shrapnel flying from a hand grenade," said astronomer...

During a period of universal warming 11 billion years ago, quasars -- the brilliant core of active galaxies -- produced fierce radiation blasts that stunted the growth of some dwarf galaxies for approximately 500 million years. This important conclusion comes from a team of astronomers that used the new capabilities of NASA's Hubble Space Telescope to probe the invisible, remote universe. The team's results will be published in the October 10 issue of The Astrophysical Journal. Using Hubble's Cosmic Origins Spectrograph (COS), the astronomers...

Astronomers using NASA's Spitzer Space Telescope have discovered that a giant star in a remote galaxy ended its life with a dust-shrouded whimper instead of the more typical bang. Researchers suspect that this odd event -- the first one of its kind ever viewed by astronomers – was more common early in the universe. It also hints at what we would see if the brightest star system in our Milky Way galaxy exploded, or went supernova. The discovery is reported in a paper published online in the Astrophysical...

A small asteroid will fly past Earth early Tuesday within the Earth-moon system. The asteroid, 2010 TD54, will have its closest approach to Earth’s surface at an altitude of about 45,000 kilometers (27,960 miles) at 6:50 EDT a.m. (3:50 a.m. PDT). At that time, the asteroid will be over southeastern Asia in the vicinity of Singapore. During its flyby, Asteroid 2010 TD54 has zero probability of impacting Earth. A telescope of the NASA-sponsored Catalina Sky Survey north of Tucson, Arizona discovered...

It's a strange-sounding name for a constellation, coming from the Greco-Roman word for giraffe, or "camel leopard". The October Camelopardalids are a collection of faint stars that have no mythology associated with them -- in fact, they didn't begin to appear on star charts until the 17th century. Even experienced amateur astronomers are hard-pressed to find the constellation in the night sky. But in early October, it comes to prominence in the minds of meteor scientists as they wrestle with the...

Scientists using data from NASA's Cassini spacecraft have learned that distinctive, colorful bands and splotches embellish the surfaces of Saturn's inner, mid-size moons. The reddish and bluish hues on the icy surfaces of Mimas, Enceladus, Tethys, Dione and Rhea appear to be the aftermath of bombardments large and small. A paper based on the findings was recently published online in the journal Icarus. In it, scientists describe prominent global patterns that trace the trade routes for material...

After nine years of scanning the sky, the Wilkinson Microwave Anisotropy Probe (WMAP) space mission has concluded its observations of the cosmic microwave background, the oldest light in the universe. The spacecraft has not only given scientists their best look at this remnant glow, but also established the scientific model that describes the history and structure of the universe. "WMAP has opened a window into the earliest universe that we could scarcely imagine a generation ago," said Gary Hinshaw,...

View larger image Hubble Space Telescope observations of comet 103P/Hartley 2, taken on September 25, are helping in the planning for a November 4 flyby of the comet by NASA's Deep Impact eXtended Investigation (DIXI) spacecraft. Analysis of the new Hubble data shows that the nucleus has a diameter of approximately 0.93 miles (1.5 km), which is consistent with previous estimates. The comet is in a highly active state, as it approaches the Sun. The Hubble data show that the coma is remarkably...

From Earth, the Sun looks like a calm, placid body that does little more than shine brightly while marching across the sky. Images from a bit closer, of course, show it’s an unruly ball of hot gas that can expel long plumes out into space – but even this isn’t the whole story. Surrounding the Sun is a roiling wind of electrons and protons that shows constant turbulence at every size scale: long streaming jets, smaller whirling eddies, and even microscopic movements as charged particles circle in...

A major instrument due to fly aboard NASA's James Webb Space Telescope is getting its first taste of space in the test facilities at the Rutherford Appleton Laboratory (RAL) in the United Kingdom. The Mid-InfraRed Instrument (MIRI) has been designed to contribute to areas of investigation as diverse as the first light in the early Universe and the formation of planets around other stars. "The start of space simulation testing of the MIRI is the last major engineering activity needed to enable...