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Mini-Comets Approaching Earth in May

Wednesday, May 10, 2006

In 1995, Comet 73P/Schwassmann-Wachmann 3 did something unexpected: it fell apart. For no apparent reason, the comet's nucleus split into at least three "mini-comets" flying single file through space. Astronomers watched with interest, but the view was blurry even through large telescopes. "73P" was a hundred and fifty million miles away.

We're about to get a much closer look. In May 2006 the fragments are going to fly past Earth closer than any comet has come in more than twenty years.

Comet 73P
Comet 73P breaking up in 1995. Photo credit: Jim V. Scotti 250X145

"This is a rare opportunity to watch a comet in its death throes—from very close range," says Don Yeomans, head of NASA's Near Earth Object Program at JPL.

There's no danger of a collision. "Goodness, no," says Yeomans. "The closest fragment will be about six million miles away--or twenty-five times farther than the Moon." That's close without actually being scary.

Credit: NASA-Full Story: Mini_Comets Approaching Earth

Discovery of Small, Rocky, Extrasolar World Suggests Such Planets May Be Common

Monday, January 30, 2006

Artists conception
Artist's concept of the newfound rocky planet circling a distant star.

Using a relatively new planet-hunting technique that can spot worlds one-tenth the mass of our own, researchers have discovered a potentially rocky, icy body that may be the smallest planet yet found orbiting a star outside our solar system.

The discovery suggests the technique, gravitational microlensing, may be an exceptional technology for finding distant planets with traits that could support life.

This important research, partly funded by NASA, is providing us the opportunity to search for planets in habitable environments," said Zlatan Tsvetanov, Terrestrial Planet Finder program scientist at NASA Headquarters, Washington. "The results successfully demonstrate the power of gravitational microlensing, currently the only ground-based technique with the sensitivity to detect extrasolar Earth-size planets on Earth-like orbits, and provide an important clue of the ubiquity of small planets."

More: NASA - Discovery of Small, Rocky, Extrasolar World

Where Art Thou Mars?

Thursday, January 26, 2006

If you are looking for Mars, According to JPl, it is at 60 degrees above the horizon at dusk and sets near 1:30 a.m. On Februrary 5, 2006, you will find Mars near the first quarter Moon, and on February 16, 2006 near the Pleiades star cluster (M45).

More:NASA -Mars Viewing Tips for 2006

Asteroid Collision Fueled Ancient Dust Storm on Earth

Wednesday, January 18, 2006

Asteroid Collision Fueled Ancient Dust Storm on Earth
Credit: Roy Britt

One of the biggest cosmic dust storms of the past 80 million years left a blanket of material on Earth after an asteroid in space broke apart, researchers said today.

The conclusion is based on evidence in ocean sediments, which computer models have tied to an observed bevy of asteroid siblings still roaming the solar system.

The thinking is that the space rocks were once part of a larger asteroid, some 100 miles (160 kilometers) wide, that broke up – possibly in a collision – out in the asteroid belt between Mars and Jupiter. The drama took place 8.2 million years ago. That much has been reasoned before. The event would have created vast amounts of dust, some of which would have been scooped up by our planet.

More: - Asteroid Collision Fueled Ancient Dust Storm on Earth

Fireball Alert!

Wednesday, January 11, 2006

FIREBALL ALERT: On Sunday morning, Jan. 15th, between 1:56 and 1:59 a.m. PST (0956 - 0959 UT), a brilliant fireball will streak over northern California and Nevada. It's NASA's Stardust capsule, returning to Earth with samples of dust from Comet Wild 2. The best observing sites: near Carlin and Elko, Nevada, (see map below) where the man-made meteor is expected to shine as much as 60 times brighter than Venus.

Map: Google maps
Credit: Image:courtesy P. Jenniskens/Seti Institute

If you're too far away to see the fireball, you might be able to hear it--on the radio. The technique is called "meteor scatter." Tune an FM radio to a silent spot between local stations and point the radio's antenna in the general direction of northern Nevada. When the Stardust capsule rips through the atmosphere, it will create an electrically ionized wake that reflects radio waves. You could suddenly pick up stations hundreds to thousands of miles away reflected in your direction from the fireball's tail. - Fireball Alert

An Explosion on the Moon

Friday, January 6, 2006

Explosion on Moon
The red dot marks the location of the Nov. 7, 2005, meteoroid impact.

Credit: NASA/MSFC/Bill Cooke
December 23, 2005: NASA scientists have observed an explosion on the moon. The blast, equal in energy to about 70 kg of TNT, occurred near the edge of Mare Imbrium (the Sea of Rains) on Nov. 7, 2005, when a 12-centimeter-wide meteoroid slammed into the ground traveling 27 km/s.

"What a surprise," says Marshall Space Flight Center (MSFC) researcher Rob Suggs, who recorded the impact's flash. He and colleague Wes Swift were testing a new telescope and video camera they assembled to monitor the moon for meteor strikes. On their first night out, "we caught one," says Suggs.

The object that hit the moon was "probably a Taurid," says MSFC meteor expert  

Bill Cooke. In other words, it was part of the same meteor shower that peppered Earth with fireballs in late October and early November 2005.

More: NASA -So you thought nothing ever happens on the moon?

New Discoveries at Uranus

Friday, January 6, 2006

Fully-labeled composite image
Fully-labeled composite image

Credit: NASA, ESA, and M. Showalter (SETI Institute)

Deep exposure of Uranus taken with the Hubble Space Telescope reveal two small moons and two faint rings. All orbit outside of Uranus's previously known (main) ring system, but interior to the large, classical moons. The outer new moon, U XXVI Mab, orbits at roughly twice the radius of the main rings and shares its orbit with a dust ring. The second moon, U XXVII Cupid, orbits just interior to the satellite Belinda. A second ring falls between the orbits of Portia and Rosalind, in a region with no known source bodies. Collectively, these constitute a densely-packed, rapidly varying and possibly unstable dynamical system.

More: SETI - New Discoveries at Uranus

Hubble Prospects For Resources on The Moon

Saturday, November 12, 2005

Apollo 17 Landing Site
Apollo 17 Landing Site, HST and Apollo mission images. NASA/ESA/HST Moon Team
Although U.S. astronauts have visited the moon before, they only spent a few days there, making short forays into the barren landscape. A new Vison for Space Exploration, announced by President George W. Bush in January 2004, calls for the establishment of human outposts on the moon and later, human exploration of Mars. This time, we're going back to stay.

To prepare for potential manned missions to the Earth's Moon, NASA scientists are using the Hubble Space Telescope to hunt for resources, such as oxygen, that are essential for people to survive and to sustain their existence on the lunar surface. Hubble's preliminary observations and results are promising. A preliminary assessment of the Hubble observations pinpoints possible locations of ilmenite, a titanium oxide rich in oxygen, at the Apollo 17 landing region. Ilmenite is a potentially key resource because it contains easily extracted oxygen, which can be used for breathing and for rocket fuel. Since the moon doesn't have an atmosphere, scientists must hunt for oxygen in lunar soils if we are to learn to live off the “land”.

More: NASA - Hubble Prospects For Resources on The Moon

Hubble Spots Possible New Moons Around Pluto

Saturday, November 12, 2005

HST images showing two new candidate satellites orbiting around Pluto
HST images showing two new candidate satellites orbiting around Pluto
The Hubble Space Telescope images shown left, taken by the Advanced Camera for Surveys, reveal Pluto, its large moon Charon, and the planet's two new candidate satellites. Between May 15 and May 18, 2005, Charon, and the potential moons, provisionally designated P1 and P2, all appear to rotate counterclockwise around Pluto. P1 and P2 move less than Charon because they are farther from Pluto, and therefore would be orbiting at slower speeds. P1 and P2 are thousands of times less bright than Pluto and Charon. The enhanced-color images of Pluto (the brightest object) and Charon (to the right of Pluto) were constructed by combining short exposure images. The images of the new satellites were made from longer exposures.

More: NASA - Hubble Spots Possible New Moons Around Pluto - view more images and get the full story on this exciting discovery!

Earth and Mars Close Encounter

Saturday, August 20, 2005

star map
Star Chart showing Mars (large red circle with symbol) rising, 20 August 2005 at 7AM UTC (midnight Arizona time).

Image Credit: Your Sky
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Earth is racing toward Mars at a speed of 23,500 mph, which means the red planet is getting bigger and brighter by the minute. In October, when the two planets are closest together, Mars will outshine everything in the night sky except Venus and the Moon. Because of the close proximity of Earth and Mars, the Mars Reconnaissance Orbiter (MRO) launch was planned for August 2006. Because it takes six or more months to reach Mars, the best time to start the trip is a month or so before closest approach--thus, August. MRO, launched August 12, will arrive at Mars in March 2006 after a seven month journey, enter orbit, and begin a two year mission to map the red planet in greater detail than ever before.

More: Science@NASA - Approaching Mars

Link: NASA - Mars Reconnaissance Orbiter

Link: Your Sky - Make your own star chart!

Tenth planet discovered

Tuesday, August 2, 2005

These time-lapse images of a newfound planet in our solar system, called 2003UB313, were taken on Oct. 21, 2003, using the Samuel Oschin Telescope at the Palomar Observatory near San Diego, Calif. The planet, circled in white, is seen moving across a field of stars. The three images were taken about 90 minutes apart.
Image Credit: NASA/JPL
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Tenth Planet Discovered

A planet larger than Pluto has been discovered in the outlying regions of the solar system.

The planet was discovered using the Samuel Oschin Telescope at Palomar Observatory near San Diego, Calif. The discovery was announced today by planetary scientist Dr. Mike Brown of the California Institute of Technology in Pasadena, Calif., whose research is partly funded by NASA.

The planet is a typical member of the Kuiper belt, but its sheer size in relation to the nine known planets means that it can only be classified as a planet, Brown said. Currently about 97 times further from the sun than the Earth, the planet is the farthest-known object in the solar system, and the third brightest of the Kuiper belt objects.

"It will be visible with a telescope over the next six months and is currently almost directly overhead in the early-morning eastern sky, in the constellation Cetus," said Brown, who made the discovery with colleagues Chad Trujillo, of the Gemini Observatory in Mauna Kea, Hawaii, and David Rabinowitz, of Yale University, New Haven, Conn., on January 8.

A name for the new planet has been proposed by the discoverers to the International Astronomical Union, and they are awaiting the decision of this body before announcing the name.

See the Full JPL News Release - NASA-Funded Scientists Discover Tenth Planet

The 2005 Perseid Meteor Shower

Thursday, July 28, 2005

star map
A Perseid sky map. The red dot denotes the shower's radiant, a point in the eastern sky from which meteors appear to stream. Image credit: Science@NASA

The Perseids come every year, beginning in late July and stretching into August. Sky watchers outdoors at the right time can see colorful fireballs, occasional outbursts and, almost always, long hours of gracefully streaking meteors. Among the many nights of the shower, there is always one night that is best. This year: August 12th.

More: Science@NASA - Mars joins the Perseid meteor shower for a beautiful display on August 12th

Transit of Venus

Tuesday, June 8, 2004

Transits of Venus across the disk of the Sun are among the rarest of planetary alignments. Indeed, only six such events have occurred since the invention of the telescope (1631, 1639, 1761, 1769, 1874 and 1882). Two transits of Venus are occuring within a few years of eachother - the first was on June 08, 2004, the next will be June 06, 2012. Transits of Venus are only possible during early December and early June when Venus's orbital nodes pass across the Sun. If Venus reaches inferior conjunction at this time, a transit will occur. Transits show a clear pattern of recurrence at intervals of 8, 121.5, 8 and 105.5 years. The next pair of Venus transits occur over a century from now on 2117 Dec 11 and 2125 Dec 08.

More: NASA Sun-Earth - Venus Transit 2004

More: Science@NASA - James Cook and the Transit of Venus

More: Space Weather - Transit of Venus Photo Gallery

Hubble's Eye on Mars

Wednesday, August 27, 2003

NASA's Hubble Space Telescope snapshot of Mars
NASA's Hubble Space Telescope snapshot of Mars

NASA's Hubble Space Telescope took this snapshot of Mars 11 hours before the planet made its closest approach to Earth. The two planets are 34,648,840 miles (55,760,220 km) apart. This image was made from a series of exposures taken between 6:20 p.m. and 7:12 p.m. EDT Aug. 26 with Hubble's Wide Field and Planetary Camera 2.

Photo credit: NASA/J. Bell (Cornell U.) and M. Wolff (SSI)

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NASA's Hubble Space Telescope made observations of the planet Mars on August 26 and 27, when Earth and Mars were closer together than they have been in the last 60,000 years. As Hubble's high-resolution images of the Red Planet are received at the Space Telescope Science Institute and are digitally processed by the Mars observing team, they will be released to the public and news media via the Internet. The Hubble images are the sharpest views of Mars ever taken from Earth. They reveal surface details as small as 17 miles (24 km) across. Though NASA's Mars-orbiting spacecraft can photograph the Red Planet in much finer detail, Hubble routinely serves as a "weather satellite" for tracking atmospheric changes on Mars and for probing its geology on a global scale.

More: NASA - Hubble Space Telescope's Viewing Plans For Earth's 'Close Encounter' With Mars

Link: Sky & Telescope - Mars at Its All-Time Finest

Mars Close Approach

Thursday, August 21, 2003

Earth and Mars are rapidly converging. On August 27, 2003 -- the date of closest approach -- the two worlds will be 56 million km apart. That's a long way by Earth standards, but only a short distance on the scale of the solar system. NASA, the European Space Agency and Japan are all sending spacecraft to Mars this year. It's a good time to go.

More: Spaceweather - Mars 2003 - Night of the Red Planet

More: NASA - Approaching Mars - Earth and Mars are converging for a close encounter in August.