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January 24, 2003
Science experiments in space
Elves and jellyfish just part of a day's work for the first Israeli
astronaut.
CYNTHIA RAMSAY SPECIAL TO THE JEWISH BULLETIN
What do dust storms, donut-shaped elves and jellyfish-like sprites
have in common with Israel's first astronaut? They are all part
of experiments being done aboard the Space Shuttle Columbia, currently
orbiting the earth on a 16-day mission. The seven-member crew of
STS-107 launched from the Kennedy Space Centre in Florida on Thursday,
Jan. 16. Among the crew is Israel's most famous space traveller
– Ilan Ramon.
STS stands for Space Transportation System (i.e. the Space Shuttle)
and 107 indicates the 107th flight of the shuttle, although the
order of missions may have changed after assignment of the flight
number. STS-107 is strictly a science mission, with more than 80
experiments dedicated to research, including three with which Tel-Aviv
University (TAU) is involved.
Ramon himself graduated from TAU in 1987 with a bachelor of science
degree in electronics and computer engineering. He has been with
the Israel air force for almost 30 years and was promoted to the
rank of colonel in 1994. In 1997, he was selected as a payload specialist
with the National Aeronautics and Space Administration (NASA).
The first TAU project, Ramon's main responsibility, is the supervision
and execution of MEIDEX, the Mediterranean Israeli Dust Experiment,
which studies the effect of dust particles on climate change. The
principle investigators for the experiment are TAU professors Zev
Levin and Joachim Joseph.
In another experiment, one of the co-investigators is Yuval Landau,
a student in the MD-PhD excellence program at TAU. Landau and Bethlehem-born
Palestinian Tariq Adwan are working on the Space Science for Peace
experiment, which focuses on the idea of Panspermia, the possibility
that life might spread between the planets by way of micro-organisms
living on and in meteors travelling through space.
Lastly, the Pathology Institute at Tel-Aviv Medical Centre, which
is associated with TAU, is studying a new liquid formula to help
improve the function of the immune and digestive systems of astronauts.
The formula, which includes probiotic "friendly" bacteria,
was created to counter the physical side effects people suffer in
space and the shuttle experiments examine the effects of the formula
throughout the duration of the flight.
Columbia's crew is split into two teams, Blue and Red, that work
12-hour shifts. This allows research to take place 24 hours a day
during the entire mission, which is due to return to Earth on Feb.
1.
Conference-call update
TAU had a "mid-mission" conference-call update on MEIDEX
earlier this week. Levin joined the call from Crete, Greece, where
the Earth-bound flight team is stationed. His colleague, Yoav Yair,
who is with Tel-Aviv's Open University, spoke from Goddard Space
Flight Centre in Maryland. Both professors are atmospheric physicists
and they shared some of the preliminary findings of the experiment
with the media, including the Jewish Bulletin.
"Already we have seen some very interesting results suggesting
that pollution coming from far away – in Europe, maybe even
eastern Europe – contain[s] quite a lot of sulfate particles,"
said Levin. "[This finding] corroborates the measurements we
have done about a year and a half ago in about the same area. Our
objective in this particular mission is to study these particular
particles and their effect on clouds under the footsteps of the
shuttle as it passes over the Mediterranean. The objective is to
look for dust or other pollutants in this region in the absence
of clouds because we want to see also the surface of the ocean."
In the MEIDEX project, a team of TAU scientists take measurements
in a plane scientifically outfitted (by Israel and the United States)
that flies in the wake of the shuttle while it passes over the Mediterranean.
The plane flies over the same area where the shuttle has taken photographs,
taking measurements to create a vertical profile of the composition
and the physical structure of the dust storms at different altitudes.
This information, as well as satellite data, will be used to interpret
the images from the shuttle, which will, in turn, hopefully help
to explain the impact these storms have on weather, precipitation,
the temperature of the atmosphere and on climate.
Unfortunately, said Levin, the experiment hasn't been that successful
so far because of cloudy weather. As well, it is not the best time
of year in which to monitor dust storms, as they are less frequent
in the winter months.
A little luck is helpful
But while MEIDEX may not have garnered many favorable results yet,
the mission has achieved other successes.
"Last night [Sunday, Jan. 19], we have come up with exquisite
images down-linked from the shuttle which show sprites and elves
dancing in the ionosphere above the major thunderstorms near ...
Australia and Borneo," said Yair. "This is a first-time
success of taking such images with a calibrated instrument [that
measures energy levels] from the shuttle and it's causing really
great excitement with our colleagues around the world."
Elves stand for "emissions of light and very low-frequency
perturbations due to EMP (electromagnetic pulses) sources,"
according to Yair. Less technically, an elf is an electrical phenomenon,
a donut-shaped luminosity glowing in red that is of really short
duration and spreads like a circle from above the thunder clouds
to a radius of about 300 kilometres, he explained. Yair described
a sprite as a type of luminious phenomenon that looks like a giant,
red jellyfish with tendrils extending from an altitude of about
80 kilometres and spreading both up and down about 20 kilometres
in both directions.
"Sprites were discovered in 1989 and elves were discovered
in 1994," said Yair. "This is a brand new alley of science
in the atmospheric electricity community and the upper atmosphere
physics [community] and it's been studied extensively, numerically
and with many observations, but the unique ability of the MEIDEX
payload is to observe this phenomena which, I have to admit, one
has to be extremely lucky to catch because it only lasts ... less
than a thousandth of a second."
The STS-107 had such luck: On the shuttle's first orbit to hunt
for sprites, astronaut David Brown managed to capture the image
of one in almost the first data take, said Yair.
Despite the fact that the sprites were not found on his shift, Ramon
is said to be enjoying his time in space.
"He is doing a lot of experiments other than MEIDEX –
medical experiments and biological experiments, as well," said
Yair. "He looks really relaxed and composed and concentrated
on the mission. I've been listening to him all day, to his ground
communication, and he is doing a great job up there."
The first results of MEIDEX are expected to be published within
six months to a year, but some parts will take perhaps two years
due to the analyses that must be performed. Another experiment taking
place on the STS-107 mission – unrelated to TAU, but Israeli-based
– is the Chemical Garden, by students at the ORT Kiryat Motzkin
middle school in Haifa and the Technion University. This project
involves growing blue cobalt crystals and white calcium crystals.
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