Many folks would like to see us back on the Moon and developing its resources.

Friday, December 23, 2005

Good day

"An Explosion on the Moon", caught my eye from Science@NASA and thought at first some
Alien Fortress had exploded. :-)

(Grandchildren are out from Ft. Leonard Wood MO and playing
Star Wars on a PS2 game station.)
An Explosion on the Moon 12.23.2005

So you thought nothing ever happens on the moon?

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

"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.
(See "Fireball Sightings" from Science@NASA.)


Suggs and his team plan to make more observations. "We're contemplating a long-term
monitoring program active not only during major meteor showers, but also at times in between.
We need to develop software to find these flashes automatically," he continues. "Staring at 4
hours of tape to find a split-second flash can get boring; this is a job for a computer."

With improvements, their system might catch lots of lunar meteors. Says Suggs, "I'm ready for
more surprises."


Read the whole article and then put on your thinking caps.

* Are they sure it was a meteor impact?
* What would it have been like if you were there?
* Would you be able to tell if this was a fresh hit if you came upon it a day later while out in your
space suit hopping around?

And HOW DO WE KNOW it was a 12-centimeter-wide meteoroid slammed into the ground traveling 27 km/s?

As a kid, my uncle gave me a bit of help in digging a hole in hard pan clay for an underground camp with a half a stick of dynamite. We blew dirt clods around the neighborhood. (was back in the time when their were still vacant lots between houses.)

I would not want to be standing near by when bits of the Moon came over the ridge. If you didn't get hit by the incoming meteor you still could get hit by secondary fall out.

The neighbors weren't all that pleased with my excavations either. :-)

Hope we get some instruments up there soon to give us some ground truth observations.

Thanks for looking up with me.

As a side note, I have mentioned that I have been helping with the saving and use of the Pioneer
10/11 Master Data Records. Dr. Slava Turyshev has finished a paper on how we might use some of the recovered information to help in the study of the Pioneer Anomaly. Viktor Toth has contributed much to the paper and yours truly had a small part. (some others at JPL as well). If you care to down load a 42 page paper you can find it at:
The Study of the Pioneer Anomaly: New Data and Objectives for New Investigation

Authors: Slava G. Turyshev, Viktor T. Toth, Larry R. Kellogg, Eunice. L. Lau, Kyong J. Lee
Comments: 42 pages, 40 figures, 3 tables

Radiometric tracking data from Pioneer 10 and 11 spacecraft has consistently indicated the presence of a small, anomalous, Doppler frequency drift, uniformly changing with a rate of ~6 x 10^{-9} Hz/s; the drift can be interpreted as a constant sunward acceleration of each particular spacecraft of a_P = (8.74 \pm 1.33) x 10^{-10} m/s^2. This signal is known as the Pioneer anomaly; the nature of this anomaly remains unexplained. We discuss the efforts to retrieve the entire data sets of the Pioneer 10/11 radiometric Doppler data. We also report on the recently recovered telemetry files that may be used to reconstruct the engineering history of both
spacecraft using original project documentation and newly developed software tools. We discuss possible ways to further investigate the discovered effect using these telemetry files in conjunction with the analysis of the much extended Doppler data. We present the main objectives of new upcoming study of the Pioneer anomaly, namely i) analysis of the early data that could yield the direction of the anomaly, ii) analysis of planetary encounters, that should tell more about the onset of the anomaly, iii) analysis of the entire dataset, to better determine the anomaly's temporal behavior, iv) comparative analysis of individual anomalous accelerations for the two Pioneers, v) the detailed study of on-board systematics, and vi) development
of a thermal-electric-dynamical model using on-board telemetry. The outlined strategy may allow for a higher accuracy solution for a_P and, possibly, will lead to an unambiguous determination of the origin of the Pioneer anomaly.


Larry Kellogg
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NASA Science News for December 23, 2005
So you thought nothing ever happens on the moon? Think again.
NASA scientists have observed a surprising and powerful explosion in the lunar Sea of Rains.


Find out about the Science@NASA Podcast feed at .


More Information

As far as they know, Suggs and Swift were the only ones who recorded the impact of Nov. 7th—"probably because we were the only ones looking," says Suggs. So, unlike the lunar Leonids of 1999 and 2001, the lunar Taurid of 2005 was not confirmed by a second or third observer.

Nevertheless, "we are 99% sure it was real," says Suggs.

Other possibilities include

a satellite passing in front of the moon, glinting in sunlight;
a cosmic ray hitting the video camera's CCD chip;
a meteor in Earth's atmosphere, directly between Earth and the Moon.
"We don't believe it was a satellite," says Cooke who, together with
aerospace engineer Heather McNamara, searched through NORAD's catalogue of 8363 "trackable objects" in Earth orbit. "There was no unclassified satellite or piece of space debris in the right place at the right time to cause the flash."

It couldn't have been a cosmic ray. "We observed the lunar explosion in five consecutive video frames (total time span: 150 msec). A cosmic ray would have caused a flash in only one frame," explains Suggs.

And finally, it almost certainly couldn't have been a meteor in Earth's atmosphere. "To masquerade as a lunar impact, a meteor in Earth's atmosphere would have to be heading directly toward our observing site at the Marshall Space Flight Center, head on, so that it looked like a point rather than a streak of light," says Suggs. "A meteoroid hitting the moon is more plausible. Furthermore," he says, "the light curve of our Nov. 7th Taurid has the same shape as light curves of lunar Leonids observed in 1999 and 2001. Also, it doesn't match the light curve of a 'point meteor.'"

Right: The light curve of the flash observed by Suggs and Swift on Nov. 7, 2005. Credit: NASA/MSFC

Fireball Sightings 11.03.2005

Earth is orbiting through a swarm of space debris that may be producing an unusual number of nighttime fireballs.

New Research into Mysterious Moon Storms
By Trudy E. Bell & Dr. Tony Phillips
posted: 07 December 2005
05:07 pm ET

Every lunar morning, when the sun first peeks over the dusty soil of the moon after two weeks of frigid lunar night, a strange storm stirs the surface.

The next time you see the moon, trace your finger along the terminator, the dividing line between lunar night and day. That's where the storm is. It's a long and skinny dust storm, stretching all the way from the north pole to the south pole, swirling across the surface, following the terminator as sunrise ceaselessly sweeps around the moon.

Never heard of it? Few have. But scientists are increasingly confident that the storm is real.

The evidence comes from an old Apollo experiment called LEAM, short for Lunar Ejecta and Meteorites. "Apollo 17 astronauts installed LEAM on the moon in 1972," explains Timothy Stubbs of the Solar System Exploration Division at NASA's Goddard Space Flight Center. "It was designed to look for dust kicked up by small meteoroids hitting the moon's surface."
Billions of years ago, meteoroids hit the moon almost constantly, pulverizing rocks and coating the moon's surface with their dusty debris. Indeed, this is the reason why the moon is so dusty. Today these impacts happen less often, but they still happen.

Apollo-era scientists wanted to know, how much dust is ejected by daily impacts? And what are the properties of that dust? LEAM was to answer these questions using three sensors that could record the speed, energy, and direction of tiny particles: one each pointing up, east, and west.

LEAM's three-decade-old data are so intriguing, they're now being reexamined by several independent groups of NASA and university scientists. Gary Olhoeft, professor of geophysics at the Colorado School of Mines in Golden, is one of them:

"To everyone's surprise," says Olhoeft, "LEAM saw a large number of particles every morning, mostly coming from the east or west--rather than above or below--and mostly slower than speeds expected for lunar ejecta."

What could cause this? Stubbs has an idea: "The dayside of the moon is positively charged; the nightside is negatively charged." At the interface between night and day, he explains, "electrostatically charged dust would be pushed across the terminator sideways," by horizontal electric fields.

Even more surprising, Olhoeft continues, a few hours after every lunar sunrise, the experiment's temperature rocketed so high--near that of boiling water--that "LEAM had to be turned off because it was overheating."

Those strange observations could mean that "electrically-charged moondust was sticking to LEAM, darkening its surface so the experiment package absorbed rather than reflected sunlight," speculates Olhoeft.

But nobody knows for sure. LEAM operated for a very short time: only 620 hours of data were gathered during the icy lunar night and a mere 150 hours of data from the blazing lunar day before its sensors were turned off and the Apollo program ended.

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