[meteorite-list] Stardust Observers Ready For Human-Made Fireball

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Sun Jan 15 00:43:46 2006
Message-ID: <200601150542.k0F5g9Z02927_at_zagami.jpl.nasa.gov>

http://space.com/missionlaunches/060114_fireball_watch.html

Stardust Observers Ready For Human-Made Fireball
By Leonard David
space.com
14 January 2006

When NASA's Stardust sample return capsule fireballs toward
a pre-dawn Utah landing this Sunday, ground and airborne observers
are ready to record the spectacular sky diving, human-made meteor.

Much is to be gained by watching the capsule's high-speed
reentry. Insight can be gained on designing NASA's post-shuttle
craft, the Crew Exploration Vehicle, as well as probe the delivery
of organics for life'ss origin by measuring the physical conditions
of the capsule as it torches through the sky.

The Stardust "mother ship" is set to release its sample-containing
return capsule on January 14 at 10:57 p.m. Mountain Standard
Time (MST).

At that time the spacecraft is 68,805 miles (110,728 kilometers)
from Earth. The capsule's entry into Earth's atmosphere
will occur at approximately 2:57 a.m. MST on January 15, touching
down at approximately 3:12 a.m. MST.

Speed demon

The 101-pound (46-kilogram) Stardust capsule is a speed demon.

When it slams into the atmosphere, it will be traveling at a
blistering 28,860 miles per hour (46,440 kilometers per hour)
- the greatest velocity ever attained by any human-made object
on record.

The peak reentry heating of the capsule is expected to occur
at an altitude of 200,000 feet (61 kilometers) above the Earth.
The main heating-phase occurs over northern central Nevada.

After zooming across the sky, the capsule's planned landing
site is the Utah Test and Training Range (UTTR), southwest of
Salt Lake City. Falling slowly by means of a deployed parachute
system, the Stardust capsule will settle down to the ground
at UTTC and then picked up by a recovery team.

The entry duration -- from hitting the atmosphere to parachute
touchdown -- is roughly 14 minutes, 20 seconds.

Getting an eye-full

Dispatched from the NASA Ames Research Center, a NASA DC-8 aircraft
will carry a team of scientists and special equipment to observe
the Stardust sample capsule as it rocket's through Earth's
atmosphere and flies to a landing in the Utah desert.

According to various sources, here are a few tips on taking
part in the Stardust capsule's dazzling plunge, visible from
central California through central Oregon, on through Nevada
and into Utah.

The Stardust capsule will approach the Utah landing zone from
a westerly direction.

The best opportunities for viewing the reentry will be along
Highway 80 between Carlin, Nevada and Elko, Nevada and further
east to the Utah border. The peak brightness of the falling
capsule will decrease further from Carlin, lessening to about
the brightness of Venus when seen from Boise, Idaho, and Salt
Lake City. Viewing will not be as good at sites east of Carlin
where the craft will be seen from behind.

There will be many other acceptable viewing sites right along
the I-80 corridor in Nevada beginning from Winnemucca, Battle
Mountain, and Dunphy, as well as Carlin. Towns such as Elko,
Nevada are close to the ground track but because Elko faces
northward, it may not be as good of a viewing site.

Look and listen

It has been noted that there are relatively few good state parks
along the capsule's path that provide public land where folks
could set up instruments and stay for a while.

One prospect is Nevada's South Fork Reservoir, which is about
16 miles south of Elko. This site is right under the projected
trajectory of the Stardust sample capsule as it flies straight
overhead about 50 miles downrange from the peak heating point.
Whether the park is open may well depend on snow conditions,
so those interested in this area should check with Nevada Division
of State Parks.

Although it is difficult to pinpoint exactly the "best" viewing
location, any site within the entry ground track and facing
south would be more ideal.

Reentry experts say that Stardust's sonic boom takes quite
a while to travel down through Earth's atmosphere. That being
the case, ground observers should listen for the boom about
three-minutes after the capsule passes overhead.

Incredibly bright...historically significant

One person that's in all eyes/all ears-mode for the sky show
is Ron Dantowitz, Director of the Clay Center Observatory at
Dexter and Southfield Schools in Brookline, Massachusetts.

Dantowitz is leader of a ground crew that departed Thursday
from the SETI Institute in Mountain View, California. Stationing
themselves in Elko, the team will choose their observing site
as the weather dictates.

"It's always a thrill when you see a random shooting star.
But here's one that you don't have to go outside and wait
for hours hoping to see," Dantowitz told SPACE.com. "This should
be incredibly bright...and historically significant."

Dantowitz and his fellow observers are set to use a unique blend
of ground-based imaging tools. "We built this all ourselves,"
he said.

Welcome mat is out

The custom-built hardware involves seven cameras and three spectrographs
that observe in the ultraviolet, to the visible, all the way
to infrared.

The specially-designed software that locks the equipment onto
the speeding Stardust capsule is the result of a decade's
work, Dantowitz said. "Once we find something, we can keep on
it."

Dantowitz said data collected will be useful for a range of
applications, from understanding the processes experienced by
incoming meteors to designing the heat shield for NASA's Crew
Exploration Vehicle.

The public is encouraged to take part in watching the capsule
reentry, Dantowitz said. Digital video and still-shot cameras,
telescopes, binoculars, radio gear -- all equipment is welcomed.

"We want to get as many people out to see this as possible,
Dantowitz said. "Every bit of data is useful. You never know
what someone might record. This should be quite beautiful."
Received on Sun 15 Jan 2006 12:42:08 AM PST