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

[Ron Baalke]

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."