Meteor/Meteorite News 29JUL2011

Meteor Activity Outlook for July 23-29, 2011 | American Meteor Society
Successful meteor watching can be accomplished by viewing in a direction that places the moon far from your field of view. The situation improves as the ...
www.amsmeteors.org/.../meteor-activity-outlook-for-july-23-2...


meteorobs : Message: (meteorobs) Radio Meteor Workshop just before ...
Dear meteor enthusiasts, No doubt you are aware that the 30th International Meteor Conference will take place in the beautiful town Sibiu, Romania, ...
tech.groups.yahoo.com/group/meteorobs/message/40107


How to photograph tonight's Delta Aquarid Meteor Shower
Examiner.com
Tonight marks the peak of the Delta Aquarid Meteor Shower, a once a year event that can produce stunning pictures. Yes, while meteor watching is a favorite past time for many, other people desire more, namely, photographing the meteors. ...


Mars Attack! UFO Appears on Live TV in Texas
IBTimes
Shocked by the live sighting, viewers speculated it could instead be a shooting star, a meteor, or even an insect reflecting light from the television tower where the camera is mounted, but a UFO, really? The public is still divided, but many viewers ...


NASA's Dawn's Spacecraft Views Dark Side of Vesta
Jet Propulsion Laboratory
Dawn took this image over Vesta's northern hemisphere after the
spacecraft completed its first passage over the dark side of the giant
asteroid. It is northern hemisphere winter on Vesta now, so its north
pole is in deep shadow. ...

Unseen Comet May Threaten Earth KSEE By KSEE News Astronomers say a surprise meteor shower spotted in February was probably caused by cosmic "bread crumbs," dropped by an undiscovered comet that could potentially pose a threat to Earth. The tiny meteoroids that streaked through Earth's ...

comet's orbit indicates possible crash
San Francisco Chronicle
Sixty specialized cameras that operate at UC's Lick Observatory, the Fremont Peak Observatory and a ground-based site, formerly in Mountain View but now in Lodi under a project called Cameras for Allsky Meteor Surveillance, constantly monitor the night ...

4 Vesta - NASA Dawn Mission Status Update 7JUL2011

http://www.jpl.nasa.gov/news/news.cfm?release=2011-206  

Dawn Team Members Check out Spacecraft
Jet Propulsion Laboratory
July 07, 2011

Dawn Mission Status Update

Mission managers for NASA's Dawn spacecraft are studying the
spacecraft's ion propulsion system after Dawn experienced a loss of
thrust on June 27. Dawn team members were able to trace the episode to
an electronic circuit in the spacecraft's digital control and interface
unit, a subsystem that houses the circuit and a computer that provides
the "brains" to Dawn's ion propulsion system. That circuit appeared to
lose an electronic signal. As a result, the valves controlling the flow
of xenon fuel did not open properly. Dawn automatically put itself into
a more basic configuration known as "safe-communications" mode, where
the spacecraft stopped some activities and turned its high-gain antenna
to Earth.

Engineers were able to return the spacecraft to a normal configuration
and restart the spacecraft's thrusting on June 30 by switching to a
second digital control and interface unit with equivalent capabilities.
One set of images for navigation purposes was not obtained on June 28
because the spacecraft was in safe-communications mode, and one other
set, on July 6, was not obtained to allow the spacecraft to spend the
time thrusting. Other sets of navigation images have been and will be
acquired as expected. The ion propulsion system is now functioning normally.

"Dawn is still on track to get into orbit around Vesta, and thanks to
the flexibility provided by our use of ion propulsion, the time of orbit
capture actually will move earlier by a little less than a day," said
Marc Rayman, Dawn's chief engineer and mission manager. "More
importantly, the rest of Dawn's schedule is unaffected, and science
collection is expected to begin as scheduled in early August."

In an unrelated event, the visible and infrared mapping spectrometer on
Dawn reset itself on June 29. At the time of the reset, the instrument
was gathering calibration data during the spacecraft's approach to the
giant asteroid Vesta. Some of its planned observations were completed
successfully before automatic sensors turned the instrument off.

On June 30, Dawn team members were able to trace the reset to an
internal error in the instrument's central processing unit, though they
don't yet know why the internal error occurred. By temporarily turning
the instrument back on, the Dawn team confirmed that the instrument is
otherwise in a normal configuration. They powered the instrument back
off, as originally planned for this time. Team members are working to
determine when they will turn it back on again.

After arriving at Vesta, Dawn will spend about one year orbiting the
asteroid, which is also known as a protoplanet because it is a large
body that almost became a planet. Data collected at Vesta will help
scientists understand the earliest chapter of our solar system's history.

The Dawn mission to Vesta and Ceres is managed by the Jet Propulsion
Laboratory, a division of the California Institute of Technology in
Pasadena, for NASA's Science Mission Directorate, Washington. Dawn is a
project of the directorate's Discovery Program, managed by NASA's
Marshall Space Flight Center in Huntsville, Ala. The University of
California, Los Angeles, is responsible for overall Dawn mission
science. Other scientific partners include Planetary Science Institute,
Tucson, Ariz.; Max Planck Institute for Solar System Research,
Katlenburg-Lindau, Germany; DLR Institute for Planetary Research,
Berlin, Germany; Italian National Institute for Astrophysics, Rome; and
the Italian Space Agency, Rome. Orbital Sciences Corporation of Dulles,
Va., designed and built the Dawn spacecraft.

To learn more about Dawn and its mission to the asteroid belt, visit:
http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov .



Jia-Rui C. Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.

Meteor/Meteorite News 4NOV2010

Did Earth Encounter Pieces Of An Alien Visitor Last Night
Space Daily
NASA meteor experts had predicted it was a long shot, but the evenings of November 2nd and 3rd might display a meteor shower from dust which puffed off this ...

Hartley 2 Spawns Meteor Shower | Universe Today
The comet of the year for 2010 seems to be Hartley 2. Although this comet is receding from Earth now (its closest approach was in the latter half of ...

Arctic lake offers up climate record
UPI.com
Cored through sediment layers at the bottom of a lake in northeastern Siberia, the record shows what happened when a meteorite smashed into the planet 3.6 ...

A Clear Voice for Science
Berthoud Recorder
The radiant points for two November meteor showers – the South Taurids and North Taurids – both reside in front of the constellation Taurus the Bull. ...
 [1010.5733] Meteor showers of comet C/1917 F1 Mellish
Abstract: December Monocerotids and November Orionids are weak but established annual meteor showers active throughout November and December. ...

 NASA Mission in Final Day Before Comet Meetup

Jet Propulsion Laboratory  -- November 03, 2010

PASADENA, CALIF. - Mission controllers at NASA's Jet Propulsion Laboratory in Pasadena, Calif., have relayed final instructions to their comet-bound spacecraft today, Nov. 3. The new programming will guide NASA's EPOXI mission through its close approach with comet Hartley 2, scheduled for tomorrow, Nov. 4, at about 7 a.m. PDT (10 a.m. EDT).

Dawn Journal
Dr. Marc Rayman - October 31, 2010
Continuing its journey to collect treats in the main asteroid belt, Dawn is making excellent progress toward its July 2011 rendezvous with protoplanet Vesta. The gentle thrust of its ion propulsion system is gradually changing its trajectory around the sun, smoothly helping the spacecraft move onto a path that will perfectly match Vesta's own motion. This pas de deux ...

Asteroid Vesta Visible 17FEB2010

Get Set for a Possible Glimpse of an Asteroid (Vesta)

http://www.jpl.nasa.gov/news/news.cfm?release=2010-051

Get Set for a Possible Glimpse of an Asteroid
Jet Propulsion Laboratory
February 16, 2010

The most prominent asteroid in the sky is currently yours for the
perusing with binoculars -- and perhaps even the naked eye.

Tomorrow night, Wednesday, Feb. 17, Vesta, the second most massive
object in the asteroid belt, reaches what astronomers like to call
"opposition." An asteroid (or planet or comet) is said to be "in
opposition" when it is opposite to the sun as seen from Earth. In other
words, if you were to stand outside with the sun directly above you at
high noon, Vesta would be directly below your feet some 211,980,000
kilometers (131,700,000 miles) away. With Vesta at opposition, the
asteroid is at its closest point to Earth in its orbit.

Wednesday night, the asteroid is expected to shine at magnitude 6.1.
That brightness should make it visible to interested parties brandishing
telescopes or binoculars, and even those blessed with excellent vision
and little or no light pollution or clouds in their vicinity. Vesta will
be visible in the eastern sky in the constellation Leo.

What makes this space rock so prominent these days? Along with its
relative proximity at this point, a full half of the asteroid is being
bathed by sunlight when seen from Earth, making it appear brighter.
Another attribute working in the observer's favor is that Vesta has a
unique surface material that is not as dark as most main belt asteroids
- allowing more of the sun's rays to reflect off its surface.

If spotting Vesta in the night sky has whetted your appetite for
mega-rocks, all we can say is, stay tuned. NASA's Dawn spacecraft,
currently motoring its way through the asteroid belt, will begin its
exploration of Vesta in the summer of 2011.

For more information about Dawn, visit: http://dawn.jpl.nasa.gov/

.

Meteorite News- Vestan Granite 26JUN09

The Complicated Geologic History of Asteroid 4 Vesta

--- Meteorites from asteroid 4 Vesta show that it contains patches of granite-like rock.

Written by G. Jeffrey Taylor
Hawai‘i Institute of Geophysics and Planetology

Planetary scientists are pretty sure that almost all of the HED meteorites come from the fourth-largest asteroid, 4 Vesta. HED stands for the three types of rocks that make up the group. As cosmochemists have studied the meteorites over the years, their view of the geologic history of the asteroid has become progressively more complicated. Jean-Alix Barrat and Marcel Bohn (CNRS and University of Brest, France), Philippe Gillet (CNRS and Ecole Normale Supérieure de Lyon, France), and Akira Yamaguchi (National Institute of Polar Research, Tokyo, Japan) have found that Vesta is even more complicated--and interesting--than we thought. ... (more) http://www.psrd.hawaii.edu/June09/Vesta.granite-like.html