YAHOO.COM - NASA
will launch a rocket tonight (Jan. 29) on a mission that promises to put
on a spectacular, albeit brief, light show over the U.S. East Coast
that may be visible to stargazers along the Atlantic Seaboard, weather permitting.
Unsuspecting observers of the artificial night sky display may
be puzzled and amazed, so before you make that phone call to your local
media outlet or police station, here is why this is happening and when
you might see it.
The bright phenomenon will be caused by an experiment aboard a NASA
sounding rocket. As part the mission, the rocket will release a chemical
tracer that should create two bright, red-colored lithium vapor trails
in space that may be seen by observers across the mid-Atlantic region, and possibly from even further away.
The rocket will be fired from NASA's Wallops Island Flight Facility
on Virginia's Atlantic coast. Liftoff is slated to occur as early as
5:30 p.m. EST (2230 GMT). The suborbital rocket, which can launch high
above Earth but not orbit the planet, will be launched tonight to test
technology for gathering science data during future projects. [NASA Rocket Launches Light Up Night Sky (Photos)]
You can watch the launch live on SPACE.com here via a webcast that will begin at 4:30 p.m. EST (2130 GMT).
By rocket's red glare
The launch window for tonight's NASA night light show opens at 5:30
p.m. EST and extends to 6:50 p.m. EST (2350 GMT), but the optimum target
time is 5:45 p.m. EST (2245 GMT). NASA intends to photograph the
resulting red luminescent trails from Wallops Island and from an aircraft as well.
You can submit any amazing photos of the launch or the resulting night sky show to SPACE.com here: spacephotos@space.com.
Should weather conditions be unfavorable, the firings will be deferred
to another night. Alternate dates run from Thursday through Friday (Jan.
30 to Feb. 1).
The sounding rocket that will be used to create the two NASA-made glowing cloud trails
will be a Terrier-Improved Orion.In this technology test launch, two
canisters in the rocket's payload section will contain solid metal
lithium rods or chips embedded in a thermite cake. The thermite is
ignited and produces heat to vaporize the lithium.
Once the vapor is released in space, it can be detected and tracked
optically. The rocket will eject two streams of lithium which will be
illuminated at high altitudes by the sun (which will be below the local
horizon at ground level).
Libby West, mission project manager with the NASA Sounding Rocket Program
at Wallops, said: "This launch is a technology test flight for two
upcoming missions. We will be testing two different methods for creating
the lithium vapor to determine which configuration is best for
observing various science phenomena in space."
During the flight, one vapor trail will occur at an altitude of about
72 miles (116 kilometers) and the second will occur at about 78 miles
(126 km) up. When heated, the lithium rods change to lithium vapor and
small amounts of lithium oxide.
The thermite reaction produces iron and aluminum oxide. The lithium
combustion process poses no threat to the public during the release in
space.
A NASA map for the mission shows the trajectory of the rocket launch,
as well as expanding circles indicating the visibility of the lithium
vapor streaks at different times.
In the map, the blue line extending out from the launch site toward the
4 o'clock position represents the trajectory of the rocket; at the end
of the blue line is where the lithium clouds will be released. The
outer yellow circle extends for a radius of approximately 400 miles (645
km), marking the boundary where the clouds will appear at a maximum
altitude of 10 degrees above the horizon. This is roughly comparable to
the width of your clenched fist held at arm's length.
The key to making a sighting is to have a clear, unobstructed view of
the horizon in the direction of Wallops Island. For example, a viewer in
Raleigh, N.C., should look toward the northeast; in New Haven, Conn.,
you should face southwest; in Philadelphia, Pa., it'll be toward the
southeast. [Amazing Stargazer Photos for January 2013 (Gallery)]
In the table accompanying this guide, I have calculated the altitude
and direction of where you should look for 15 selected cities.
If you live along the Atlantic Seaboard and live outside of the yellow circle, you should still make an attempt to try and see the lithium clouds.
At an altitude of 78 miles, theoretically they might be seen as far as
850 miles (1,370 km) from the release point. Their altitude will be less
than 10 degrees above the horizon, but assuming your sky is free of any
cloud cover or haze and you have an unobstructed view in the direction
of Wallops Island, you certainly will have a chance of getting a glimpse
of this atmospheric experiment.
Viewers as far north as southern Quebec and Nova Scotia and as far
south as northern Florida might be able to catch the clouds as low as
five degrees above the horizon.
For places situated to the west, toward the Ohio and Tennessee River
Valleys, there will be a caveat in that the sun will have only recently
set and the twilight sky may still be too bright to see the artificial
clouds.
The gusty jet stream
Looking up along the trajectory from the ground, such chemical trails
often appear distorted in complex ways. Among other things, their shape
provides scientists with precise data on wind speeds and directions
at various levels of the upper atmosphere. [Earth's Atmosphere from Top to Bottom (Infographic)]
The jet stream at nearly 80 miles (128 km) above the Earth's surface is
much higher than the one commonly reported in weather forecasts. The
winds found in this upper jet stream typically have speeds well over 300
mph (482 kph) and create rapid transport from the Earth's mid latitudes
to the polar regions.
This jet stream
is also located in the same region where strong electrical currents
occur in the ionosphere. It is therefore a region with a lot of
electrical turbulence, of the type that can adversely affect satellite
and radio communications.
NASA plans to launch two more missions his year that will use the lithium trails to assist scientists in observing events in space.
The first launch will blast off in April from Kwajalein Atoll in the
Marshall Islands, located out in the central Pacific Ocean. The second
flight will occur in June, again at the Wallops Flight Facility in Virginia.
Last year, NASA launched five sounding rockets in five minutes to
create a spectacular light show that amazed stargazers all along the
Eastern Seaboard.
"We're Being Invaded!"
NASA used to conduct chemical cloud experiments from Wallops Island
much more frequently during the 1960s, '70s and '80s, usually in the
predawn hours when most people were asleep. Chemicals such as tri-methyl
aluminum, barium and tri-ethylborane were used, often creating rather
exotic colors of red, green and purple.
When such launches took place during convenient evening hours they
usually took people by surprise. In March 1967, when three clouds were
released around 7 p.m. they were followed by countless numbers of people
all along the East Coast calling newspapers and police stations, asking
for explanations of the strange sightings. One man described the rocket
residue as "red balls of fire."
In January 1975, a barium cloud was released at around 5:30 p.m. in the
evening. As luck would have it, the town of Riverhead, N.Y., was hit by
a power outage at the very same moment that the cloud appeared in the
sky.
This resulted in a panic among the local residents who believed that
the cloud had something to do with the loss of their power. One man
called the local police station and shouted: "We're being invaded! I
can see the spaceship in the sky right now … it's glowing with a
greenish color and expanding as it's draining us of our electric power!"