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Jet Propulsion Laboratory UNIVERSE
Pasadena, California - Vol. 23, No. 7 - April 9, 1993
_________________________________________________________________
Mars Observer mapping mission to begin earlier than planned
By Diane Ainsworth
The Mars Observer spacecraft will begin its mapping mission
about three weeks sooner than planned to ensure that data
collection is well under way before Martian dust storms begin to
sweep over the planet in February 1994.
Plans to begin the science experiments on Nov. 22, 1993,
rather than Dec. 12, had been written into the baseline strategy
for the mission, but could not be considered until fuel surplus
after launch and the first trajectory correction maneuver had
been determined, project officials said. The Mars Observer
planetary science group ratified the decision in mid-February to
begin science observations 21 days ahead of schedule.
"We had ideal launch conditions," said Suzanne Dodd, Mars
Observer mission planning team chief, "and the Titan III launch
vehicle and Transfer Orbit Stage (TOS) booster performed so
efficiently that we conserved enough fuel to begin the mission
early."
The spacecraft will use the "power in" approach to drop more
rapidly into its final, two-hour mapping orbit, Dodd said.
Spacecraft descent from the time of capture in Mars orbit until
it reaches the mapping orbit will take 75 days rather than 96
days, and will require seven braking maneuvers to bring the
spacecraft into its 2 p.m. solar orientation.
The spacecraft's booms will not be fully deployed until the
final polar orbit has been achieved, Dodd said, but some science
experiments will be operating as the highly elliptical orbit
begins to tighten around the planet.
The Magnetometer and Gamma Ray Spectrometer -- mounted on
separate booms -- will be able to make unique measurements of the
interactions of magnetic field lines with the solar wind that
will not be observable from the lower altitude mapping orbit,
said Dr. Arden Albee, Mars Observer project scientist.
"For the first 10 1/2 days, the spacecraft will be crossing
in and out of the planet's magnetic field in a three-day
elliptical orbit," Albee said. "This will be a critical period
for Magnetometer and Gamma Ray Spectrometer calibrations. Noise
from the spacecraft will have to be subtracted out from the
magnetic signatures of Mars and that can only be done as the
spacecraft moves closer and then farther away from this planetary
boundary."
Twenty-one days after orbit insertion, the spacecraft will
be in a one-day orbit around the planet. The Deep Space Network
will begin to track the spacecraft continuously and, using the
Doppler shift, measure the Martian gravity field.
The Thermal Emission Spectrometer and Mars Observer Camera
may also be operated simultaneously during spacecraft descent,
Dodd said. Those instruments had not yet been approved for
operation when Universe went to press, but a decision was
expected within a few weeks. The camera, which will have taken
its first picture of the planet 28 days before orbit insertion,
would be turned on to begin acquiring narrow-angle images of star
fields and the limb of the Martian surface.
Mission operations team members said a solar conjunction
that will occur on Dec. 20, 1993, and last through Jan. 3, 1994,
also prompted the decision to begin science operations early.
During the conjunction, the sun will be between Earth and the
spacecraft, blocking spacecraft communications.
"From an operational standpoint, we wanted to make sure that
all orbit maneuvers and boom deployments were completed before we
lost communication with the spacecraft," Dodd said. "On the
science side, one complete mapping cycle takes 26 days, so we
wanted to have one nice, clear map of Mars before solar
conjunction."
"There is a very distinct advantage to getting this first
mapping cycle right up front," Albee added. "The Martian dust
storms run roughly between February and August, so the atmosphere
should be very clear in November. It will also provide us with an
excellent opportunity to obtain data before and after a dust
storm."
Mars Observer will reach its near-circular mapping orbit 378
kilometers (234 miles) above the planet's surface on Nov. 8 of
this year. At that time, the last two solar panels will be
deployed and the science booms will be fully extended. In its
mapping configuration, the spacecraft will map the red planet for
an entire Martian year, the equivalent of about two Earth years
or 687 Earth days. ###
_________________________________________________________________
Lab's women leaders share successes, struggles
by Karre Marino
The Advisory Council for Women's final lunchtime discussion
in recognition of Women's History Month on March 31 was, as Lab
Director Dr. Edward Stone noted in his opening remarks,
"appropriately enough, led by the women of JPL who are making
their own history." Eight women who have broken ground and made a
name for themselves in their field and on Lab related their
stories of struggle, success and contributions. They also advised
an overflow crowd on just how one breaks into a largely
male-dominated organization.
Marcia Neugebauer, a senior scientist in the Space Physics
and Astrophysics Section 328 whose JPL career began in 1956,
described the three phases she has experienced in the treatment
of women: the days when men ran the Lab and women were rare; the
days when performance was all that mattered and spoke volumes;
and today, when "people are leaning over backward to be sensitive
to affirmative action programs, which sometimes leads me to
wonder how much of my recognition is based on the quality of my
work and how much is due to gender."
Most of the panel members concurred with this view. In fact,
an overriding theme was while women have obviously made progress,
the journey is far from complete. "I came to the Lab in 1977, and
since then, I've noted a change in management's attitudes toward
women," said Martha Hanner, a senior research scientist in the
Atmospheric and Oceanographic Science Section 324. More women are
being sought to fill technical slots, but the bottom line at JPL
-- which the panel seemed to like -- was that one is judged on
their performance.
"JPL recognizes extreme excellence," said Merle McKenzie,
manager of JPL's International Affairs Office. She said that
participating in outside activities and making connections is a
great way for women to gain positions they want.
Barbara Brown, manager of the Containerless Processing
Project in the Office of Space Sciences and Instruments, began
with JPL in 1971 after becoming in 1967 the first woman to
graduate from Cal Poly San Luis Obispo with a degree in
electrical engineering. She lauded the benefits of hard work,
determination and "positive thinking."
"When I came here to work on Viking, I became a group
supervisor and then a deputy section manager -- all fairly
quickly. I think that was because I saw things that needed to be
done and did them," Brown explained to the mostly female
audience.
Jean Dickey, supervisor of the Space Geodetic Science and
Applications Group, joined JPL in 1980 after having spent years
on Caltech's research faculty, and noted that there are so many
opportunities for doing interesting, important were here. "It's
like being in a candy shop," she said.
Catherine Thornton, manager of the Tracking Systems and
Applications Section 335, said that in 1961, when she signed on
with JPL, "I was making $650 a month." While today that salary
elicits laughter, Thornton was serious from day one: The work
here was challenging, stimulating and competitive. She too noted
the opportunity to engage in a wide variety of projects. And
while she admitted that "management's sensitivity to women is
good, I always like to feel that when competing for a position, I
am chosen because I'm competent, not because I'm a woman."
After 24 years with Tampa's University of South Florida,
Glenda Lentz decided she wasn't too old to make a cross-country
move and join "the special people at JPL." As manager of the
Recruitment and Staffing Section 616, she agreed that women will
move up via hard work. "I see firsthand JPL's effort to hire more
women in technical positions."
Her advice to young women interested in careers at JPL?
"Don't give up your goals. I earned both my undergraduate and
graduate degrees when I was a wife and mother. It's not the ideal
way to do it, but it can be done."
Seventeen years ago, Donna Pivorotto, who now manages of
Lunar and Planetary Science Rovers, did experience sexism at JPL,
but "there was no discrimination. If you performed well, you had
no problems." However, she said, when it came to competing with
men for jobs, "it wasn't so great." She acknowledged the
importance of mentors in making progress, explaining that her
promotions and salary increases were "directly related to whether
or not I was working on a project with a mentor."
A Q&A session ended the discussion, and while a few audience
members were concerned that many young women aren't being
encouraged to choose science as their profession, Lentz said that
54 percent of JPL's new technical graduate hires were women.
Stone called the series of seven presentations "an ambitious
project" that "was both thoughtful and stimulating," and he
thanked the ACW for its participation. ###
_________________________________________________________________
Process Action Team succeeds in cutting signature levels
By Mark Whalen
Sign this, sign that. Sign here, sign there.
Among the myriad of responsibilities they hold, assistant
laboratory directors have to sign a ton of documents signifying
their approval of a wide range of plans, proposals and
agreements. But late last year Dr. Charles Elachi, ALD for the
Office of Space Science and Instruments, decided enough was
enough.
Soon thereafter, the OSSI Process Action Team (PAT) on
Signatures was born, and the way was cleared for a smoother and
more efficient signature process involving forms which originate
in or are routed through OSSI.
The seven-member PAT, headed by team leader Merle Ruiz,
manager of OSSI's Program Administration Office, recently
completed its work after starting last December. What follows may
be a blueprint for efficiency that can be applied to the
signature process across the Lab.
In keeping with the philosophy behind PATs, Ruiz' group
represented a good cross-section of OSSI: Christina Alvarado,
project secretary for SIR-C; David Nichols, manager of the
Advanced Spaceborne Thermal Emission and Reflection Radiometer
(ASTER) Project; Peggy Rice, administrative specialist, OSSI
program administrative office; Clara Sneed, OSSI administrative
assistant; and Amy Walton, assistant program manager of the Earth
and Science Program. In addition, Elizabeth Emmons, technical
division administrator of the Earth and Space Sciences Division
320 was part of the team.
Ruiz said team members began by reviewing all 277 forms in
the JPL Stationery Catalog to identify where the number of
signatures for different processes could be reduced, but
concentrated on two areas -- proposals in response to NASA
Research Announcements, and Research and Technology Operating
Plans (RTOPs) -- because "that's how research science and
engineering gets funded at JPL," she said.
Also receiving special attention, she said, were
"signature-heavy activities" relating to detailee and assignee
letters and Memos of Understanding (MOUs), which are
personnel-related forms involving assignments mostly to NASA
Headquarters.
An example of this is when OSSI receives a request from
headquarters for a detailee to support a NASA program. "Just to
send a reply letter back to NASA takes seven signatures," Ruiz
noted. "This doesn't commit any money; it just identifies the
person. The MOUs also require from eight to 10 signatures, so
those processes were prime candidates for streamlining."
In the course of its review, the team developed an initial
goal of reducing the signature process to a minimum of three
signatures, "up to and including the highest level necessary,"
Ruiz said.
In the early stages of the process, the team shifted its
focus to identify the "appropriate and minimal" number of
signatures, she added.
After gaining a consensus from all offices involved and
OSSI management on their plans, the revisions were initiated to
the Standard Practice Instructions, "the bible of the
Laboratory," Ruiz said.
The signature process review took close to three months to
finish, although Ruiz said that the team originally thought it
could complete the process in a few weeks. They soon found out,
she said, that "there are a lot of variables to consider; you
can't work in a vacuum, and you need consensus from various
offices.
"One of the things that we found in meetings with various
managers, deputy ALDs and (Deputy Director) Larry Dumas is that
people are willing to look at how we do business and make
appropriate changes, and that's really refreshing," Ruiz said.
"If we don't have that kind of support from upper management,
we're really going to be spinning our wheels. We might produce a
lot of nice reports, but changes will not occur."
Other factors working in the team's favor, she added, were
the small size of the PAT (seven) and the fact that they utilized
the tools of the Total Quality Management (TQM) initiative to
keep them focused, particularly the "FADE" process to ensure
continuous improvement: focus on the problem; analyze influential
factors; develop solutions; and execute plans.
The impact of the OSSI Signatures PAT's work is already
being felt, according to Ruiz, who noted that Office of
Administrative Divisions ALD John Heie recently asked his
organization to identify areas that could be streamlined in their
signature process.
Also, TQM Coordinator Mary Wong said she sent a copy of the
team's final report to facilitators of the introductory course in
TQM -- The Quality Advantage -- "as another example of "how TQM
is being applied.
"It's also a nice document for PAT facilitators," Wong said.
"It outlines the procedure the team went through, so it's a good
road map for any team that wants to tackle a similar issue."
Ruiz indicated that the team will follow up on its work in
six months through informal discussions with affected offices.
When asked if the team's findings can be applied to any
project or organization on Lab, Ruiz replied, "Absolutely. And
now that we have gone through the entire process, and actually
came up with a result that is now being implemented, it gets you
excited about other things the Lab does, and how everybody can
benefit from what we learned." ###
_________________________________________________________________
News briefs
JPL Director Dr. Edward Stone has appointed Ronald Ploszaj
deputy assistant laboratory director in the Office of Technical
Divisions.
Ploszaj replaced Dr. James King Jr., who was recently named
ALD for the same organization.
Since 1987, Ploszaj has served as manager of the Mechanical
Systems Engineering and Research Division 350.
Ploszaj joined JPL in 1967 as a spacecraft systems engineer,
and later held managerial positions in Flight Projects and the
Technology and Applications Program Office.
Gary W. Savona, a television producer/director in JPL's
Audiovisual Services Office, has won a 1993 silver Telly Award
for outstanding video production of "Mapping the Martian World:
The Mars Observer Mission."
The seven-minute news clip of the Mars Observer mission was
distributed to news media just before launch of Mars Observer on
Sept. 25, 1992. The clip continues to be used in television
coverage and educational programs on the Mars Observer mission,
which begins its mapping mission in late November.
Savona, who won the first- place award in the public
relations category, was among 8,000 entrants competing in this
year's awards. The Mars Observer video was narrated by Neil Ross;
the music was composed by Charles Phillip White; the script was
written by Diane Ainsworth. Computer animation was provided by
Vibeke Sorensen, Eric De Jong and Shigeru Suzuki. Savona also won
last year's 1992 first place Telly Award for a Magellan video
production, entitled "Magellan: Mapping the Planet Venus."
The Telly Awards were founded in 1980 to showcase and
recognize outstanding work in non-network and cable television
commercials, film and video productions, and non-network
programming.
JPL's Archives and Records Office is looking for donations
of past issues of Universe to complete its collection.
Universe issues with the following dates are being sought:
Dec. 26, 1970; June 6 and 20, 1981; May 7 and June 4, 1982; Aug.
13, 1983 through May 12, 1989. Also needed is the
November/December 1975 issue of Universe's predecessor,
Lab-Oratory.
If you can donate any past issues of Universe, contact Julie
Cooper at ext. 7-7119.
A Retirement Fair themed "Planning for Tomorrow" will be
presented on the Mall April 24 to assist employees in planning
for a secure and satisfying retirement.
JPL's Employee Compensation, Services and Records Section
614 will host the event from 9 a.m.-1:30 p.m. It will feature
workshops and information booths on retirement, health care and
financial services. Also, JPL and Caltech retirees will talk
about their experiences in planning, implementing and enjoying
retirement.
A new multimedia planetarium show titled "SETI--The Search
for E.T." is underway at the Griffith Observatory.
The presentation is based on JPL's High Resolution Micro-
wave Survey, and is shown Tuesday through Sunday at 3 p.m. and
7:30 p.m., with additional shows at 4:30 p.m. on Sunday.
Call (213) 664-1191 for information. ###
_________________________________________________________________
JPL Science Fair plays host to
Eliot Middle School's future stars
By Karre Marino
Some 115 sixth, seventh and eighth graders from Eliot Middle
School were filled with hope as they awaited the judges'
decisions in JPL's annual three-day Science Fair, which began in
von Karman Auditorium March 23.
Students endured three to five rounds of judging, as about
70 JPL staffers used a checklist to score the myriad projects in
the competition, hosted by the Lab's Public Services Office.
Judges were looking for a variety of information, including
aspects of creativity, scientific thought/ engineering goals,
thoroughness, skill and clarity. Oral interviews were an integral
part of the judging process, as students were scored on their
answers to 10 questions about their projects.
The students initiated projects on a wide spectrum of
scientific questions, including: how the respiratory system
works; which substance -- air, water, soil or gravel -- retains
the most heat; whether exercise increases or decreases one's
blood pressure; how plants respond to light and liquids; the
safety of drinking water, and many others.
Students provided charts, graphs, photography and drawings
in their presentations, and written reports featured abstracts,
hypothesis, a review of the literature, data and conclusions.
Rheanna Hafner, who took the first-place prize among
eighth-graders, studied core samples of white elder trees in an
attempt to discern rainfall's impact on growth. She found that
"trees grow fastest in the first five years, and by the 25th
year, growth slows." While she enjoys science, Hafner said she
plans to become a lawyer.
Musician and science fan Peter Glover combined his interests
in an experiment that asked: How does bow style affect the sound
a cello produces? "I used to think they all made the same sound,"
he admitted. But after his study, which merited a second-place
win, he now knows that different size bows produce different
sounds -- "sound" knowledge Peter can now apply to his music,
since he plays in the Eliot School orchestra.
Jody Simmons was curious about how our eyes respond to
color. He found that after concentrating on a large red X for 20
seconds, when one looks away and glances at a blank page, they'll
see a blue X. "I tried it on all of my family members, and they
all saw blue," he explained. The seventh grader, who likes math
and English as much as science, and hasn't counted out a career
in research, placed ninth for seventh graders.
While all of these students are special, they're not all 4.0
scholars. They simply have an interest in science, explained
William Patterson, Eliot seventh grade counselor. "Some kids are
repeat winners, and some have siblings who have taken part in the
fair," he explained. He attributed their success and motivation
to parental encouragement and interest. "Many parents help out on
the projects. And of course, the science teachers worked closely
with all of the kids. They've gotten lots of support at home and
at school."
Besides Hafner, first-place finishers were Courtney Cooper
(seventh grade), whose project was titled "Sugar vs. ant food,"
and Oluremi Alaba (sixth grade), who wondered "How is osmosis
affected by the size of a molecule?"
The top nine finishers in each grade were awarded ribbons
and certificates in a von Karman Auditorium ceremony March 25.
###
_________________________________________________________________
Workshop focuses on smaller science instruments
How to shrink scientific instruments to fit on new, smaller
spacecraft of the future was the focus of a JPL/NASA workshop
that drew some 80 scientists from four countries to Pasadena last
week.
According to workshop host Dr. Bruce Tsurutani of the Space
Physics and Astrophysics Section 328, NASA engineers are
currently being challenged to design spacecraft that are smaller,
lighter in weight and that use less power.
In order to achieve that goal, researchers must first make
the spacecraft's payload -- its complement of sensors -- smaller,
lighter and more energy-efficient.
The workshop focused on instruments that study "fields and
particles" -- that's to say, the magnetic fields and charged
particles such as the ions that stream out from the sun through
the solar system in the solar wind.
Besides focusing on instruments themselves, participants
discussed associated electronics such as power supplies and data
systems.
Participants discussed new miniaturized scientific
instruments and electronics for such JPL mission concepts as
Solar Probe, a spacecraft that would orbit close to the sun;
Interstellar Probe, which would send a spacecraft out of the
solar system to sample the space environment between the stars;
and Pluto Fast Flyby, which would send a spacecraft past the
distant planet Pluto and its moon, Charon;
As part of the workshop, participants toured JPL's
Microdevices Laboratory, hosted by Dr. Barbara Wilson and Dr.
Michael Hecht. ###
_________________________________________________________________
3 spacecraft help in search for Einstein-predicted gravity waves
By Franklin O'Donnell
During an otherwise quiet part of their interplanetary
cruises, three JPL spacecraft are being used in a novel
experiment to find something that Albert Einstein predicted but
no one has yet detected directly -- gravity waves.
The experiment, which began March 21 and ends Sunday, April
11, makes use of the Mars Observer, Galileo and Ulysses
spacecraft, all currently cruising en route to their respective
destinations.
During the three-week effort, antennas of JPL's Deep Space
Network have been sending signals to each of the spacecraft,
which in turn sends a signal at the same frequency back to Earth.
Any slight change in the frequency could be caused by a
passing gravitational wave emitted by a collapsing black hole or
other distant celestial event.
"Albert Einstein predicted the existence of gravitational
waves in his theory of general relativity, and radio astronomy
observations of pulsars have suggested they indeed exist -- but
no one has ever detected a gravitational wave directly," said Dr.
John Armstrong of JPL's Radio Frequency and Microwave Subsystems
Section 333, who is working with the Mars Observer and Galileo
spacecraft.
According to Einstein, waves of gravity are emitted by
astrophysical bodies undergoing extreme acceleration. The waves
themselves are ripples in the fabric of space-time moving at the
speed of light.
Some cosmic events major enough to produce gravitational
waves that could be detected near Earth include collapses of
masses of stars in the hearts of galaxies and the spiraling
together and collision of two black holes.
Detection of gravitational waves will give scientists new
information on the interiors of these catastrophic events.
Sensitive interferometer antennas are being built in the United
States and Europe to search for gravitational waves with
wavelengths of thousands of kilometers.
"In addition to searching for the shorter waves that can
affect antennas here on Earth, we can use radio signals sent to
spacecraft hundreds of millions of kilometers away to search for
waves of much longer wavelength," said Dr. Frank Estabrook of the
Space Physics and Astrophysics Section 328, who is working with
the Galileo spacecraft.
If strong enough, a passing gravitational wave will warp the
fabric of space between the spacecraft and Earth so that the
frequency of the spacecraft's radio signal changes.
The hydrogen maser clocks that control the DSN transmitters
and receivers are so accurate that scientists are be able to
detect a change in radio frequency of as little as a few parts in
a quadrillion (1 followed by 15 zeroes).
"This should allow us to detect gravitational waves from
objects such as massive pairs of black holes hidden in the hearts
of other galaxies," said Hugo Wahlquist of JPL (also from Section
328), who is working on the Ulysses spacecraft with JPL's Sami
Asmar (Section 339), Prof. Bruno Bertotti of the University of
Pavia, Italy, and Prof. Luciano Iess of the University of Rome La
Sapienza.
The experiment is the first time observations have been made
simultaneously with multiple spacecraft, which greatly increases
the reliability of any detection.
The team acknowledges, however, that snaring a gravitational
wave during the experiment will depend on a good bit of luck
--whether or not a suitable astronomical event happens to occur
during the three-week opportunity when data can be taken.
The three spacecraft are all in the night sky currently, so
interference with their radio signals due to charged particles in
the solar wind is at a minimum.
Mars Observer, launched in September 1992, will reach the
red planet Aug. 24 of this year. Launched in 1989, NASA's
Galileo spacecraft will arrive at Jupiter in 1995. The joint
NASA-European Space Agency Ulysses spacecraft was launched in
1990 to fly over the sun's poles in 1994 and 1995. ###
_________________________________________________________________
Magellan will change orbit,
attempt aerobraking in May
The Magellan spacecraft, which has mapped the surface of
Venus with imaging radar, will be put into a near-circular orbit
in a process called "aerobraking" beginning in late May, said
Magellan Project Manager Doug Griffith.
Griffith explained the process in a noontime lecture in von
Karman Auditorium March 26. The essence of the aerobraking
process requires the spacecraft"s lowest orbital point,
periapsis, to be placed in the upper Venus atmosphere. That
allows atmosphere-induced "aerodynamic drag" to reduce the
spacecraft velocity and circularize the orbit.
It will be the first time a NASA spacecraft has been
aerobraked at a distant planet, and the experiment is expected to
provide valuable information for future missions.
Magellan, which completed mapping the planet last September,
is making gravity observations in its fourth 243-day cycle around
Venus. At the end of the cycle, on May 25, spacecraft controllers
will perform an orbit trim maneuver to lower Magellan's periapsis
altitude. Aerobraking operations will then start, and the process
is expected to take about 70 days.
The near-circular orbit would be from 200 kilometers to 300
kilometers (124 to 186 miles).
After circularization has been accomplished, Griffith said,
the project will perform high-resolution gravity studies, pending
NASA approval, through October 1994. Funding has been requested
to extend the mission for that period, he said. ###
- end -