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- T H E P R O B E
- ____________________________________________________________________________
- O K C R A N G E R A E R O S P A C E A S S O C I A T I O N
- ______________________________________________________________________
- M a y N e w s l e t t e r 1 9 9 1
- _________________________________________________________________
- VOLUME 2 NUMBER 4
- =========================================================
-
-
- THE PROBE
- ELECTRONIC VERSION
- VOLUME 2; ISSUE 4 MAY 1991
- Published by the Oklahoma City Ranger Aero-Space Association
- (OKC-RASA)
-
- For more information about RASA, please send a SASE to:
- RASA
- c/o Mark Hardaway
- PO Box 800201
- Oklahoma City, OK 73119
- (405)681-3165
-
- You can also post a message ATT: Micheal Moery on the
- HAL-9000 BBS (405)682-1177.
-
-
- Subscription rate for THE PROBE is $15.00 and includes membership
- in RASA. Make checks payable to Mark Hardaway. Please allow 4 to
- 6 weeks for delivery.
-
-
-
- RASA REPORT
- By Mark Hardaway
-
-
- Greetings once again to all of our friends and welcome to those
- of you who are joining us for the first time. Please fasten your
- seatbelts and extinguish all smoking materials as we prepare for launch.
- Carolyn Snavely was our special guest speaker at the April meeting.
- Carolyn, as many of you may know, is one of Oklahoma's NASA Teacher in
- Space Finalists. Carolyn shared with us much of interest during our
- informal discussion, including the story of how she got started in the
- space program. At the end of the meeting, the Board of Directors voted
- unanimously to make her an honorary member of RASA. Carolyn was a
- wonderful guest and we hope to see her again soon.
- Our guest speaker for the May 19th meeting was to be Johnathan Majid,
- Architect AIA. His offices are located here in Oklahoma City at 3324
- Classen Blvd. Mr. Majid is a designer, architect and builder of
- underground or earth sheltered dwellings. It was with much regret and
- sorrow that we decided to cancel the planned program. After a phone
- survey and a quick nose count, we discovered that the meeting would not
- be attended by as many as had been hoped for. Therefore, we felt that
- it would be in the best interest of everyone to seek a postponement.
- However, Mr. Majid did agree to reschedule his engagement for sometime
- this fall, and we will preview his talk with an interview. Again we
- thank Mr. Majid for his time and patience.
- THUNDERCON '91!! On May 31, June 1 & 2, at the Central Plaza Hotel,
- which is near the I-40 and Eastern intersection, will be embarking upon
- a 3-day mission to explore the known and the unknown universe of OKC
- 'STAR TREK' fandom. The price for this grand 3-day adventure is a paltry
- 18 dollars at the door. BE THERE !!! RASA has been asked to participate
- in a panel discussion on NASA & Futures in Space to be held Sunday at
- noon in Main Programing. By the way, we will be holding a Spacers Room
- Party on Friday evening and serving Hydrozine, a rocket fuel component
- in its stabilized form. ENGAGE !
- AEROSPACE AMERICA '91 enters its sixth year. On Father's Day weekend,
- June 14-16, aviation takes on a new meaning by bringing our world a little
- closer together in search of answers to global questions and worldwide
- peace. Oklahoma City and the Oklahoma City All Sports Association presents
- Aerospace America '91 in memory of Tom Jones, co-founder. Gates open at
- 5 p.m. Friday, and at 9 a.m. on Saturday and Sunday. Tickets are $6.00 in
- advance and $9.00 at the gate, children (6-12) are $3.00 and $5.00. Anyone
- wishing to volunteer to work the airshow should contact Micheal Moery
- or Mark Hardaway before June 3rd.
- Because of the airshow, we are moving our June meeting to the following
- week. Our June meeting will be held at the Air-Space Museum, Kirkpatrick
- Planetarium on Sunday, June 23, at 3:30pm. This will be our first meeting
- held at these facilities. We are all looking forward to the experience.
- On June 29 the STAR-OKC/RASA fossil hunt and star watch is expected to
- take place in Southeastern Oklahoma with Kevin Hopkins as our tour guide.
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 2
-
-
- OUR VISION
- by Mark Hardaway
-
-
- As the resolve of the Ranger Aero-Space Association (RASA) moves
- forward in its commitment to promote space exploration, research,
- and development in Oklahoma and abroad, it is important to continue
- to redefine our direction and to make our intentions clear.
-
- We are a grass-roots organization committed first to City, State,
- Nation, and our World. Although we are not primarily a lobbyist
- group, we do support those national lobbying consortia who express
- our ideals and we will add our voices to any effort that meets that
- criteria.
-
- The purpose of RASA is to enlighten the public and to gain their support
- for continued space exploration. It is our contention that an aggressive
- space program is the only viable solution with a peaceful mandate that
- can successfully or effectually stimulate our economy. Furthermore,
- the space program has given mankind the technology and ability to solve
- many of the world's problems including issues of environment, health,
- education, and welfare.
-
- Our meetings are the workshops that research and produce our plan of
- action. They are informal and have the feel of a "think tank" session.
- Our newsletter is dedicated to all of those who have a genuine enthusiasm
- for space and science.
-
- We hold the future dearly and wish to have a part in educating future
- generations so that their hold may be firm. We believe that the children
- of today are the leaders of TOMORROW.
-
-
-
-
- EDITOR'S NOTE
-
- THE PROBE is a monthly newsletter published for the benefit and enjoyment
- of the members of RASA. Reader submissions to the newsletter are encouraged
- and, in fact, essential. Articles are to be about space or aeronautics,
- either factual or speculations based on realistic technology and research.
- All articles will become the property of the editor unless a self-addressed,
- stamped envelope is provided by the author. Submissions may also come in
- the form of an IBM/AT computer data file, either on floppy disk or posted
- ATT. MICHEAL MOERY on the HAL-9000 BBS (682-1177.) Deadline for submissions
- shall be the Monday before the RASA meeting date. Any opinion expressed
- in the newsletter is that of the author and not that of the editor or staff
- of THE PROBE.
-
- Submissions are to be sent to:
-
- THE PROBE
- c/o Micheal Moery
- 2401 NW. 122nd Apt. 242
- Oklahoma City, OK 73120
- (405)751-2113
-
- Any submissions that arrive after the deadline will be considered for a
- future issue.
-
-
-
-
- NEWSLETTER STAFF
- AND
- BOARD OF DIRECTORS
-
- PRESIDENT/
- LAYOUT & DESIGN ......... T. Mark Hardaway
- EDITOR-IN CHIEF/
- BOARD MEMBER .............. Micheal D. Moery
- ASST-EDITOR/
- VICE-PRES .............................. Angie R. Berry
- SEC/TREAS ................................. Myron Moody
- BOARD MEMBER ........................ Karen Mauer
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 3
-
-
- FIRST SPACELAB DEDICATED TO LIFE SCIENCES HIGHLIGHTS STS-40
-
- Shuttle mission STS-40, the 41st flight of the Space Shuttle and
- the 11th flight of Columbia, will conduct the Spacelab Life Sciences
- (SLS-1) mission, the first spacelab dedicated to life sciences research.
- During the SLS-1 mission, the STS-40 crew will perform experiments
- which will explore how the heart, blood vessels, lungs, kidneys and
- hormone-secreting glands respond to microgravity, the causes of space
- sickness and changes in muscles, bones and cells during the microgravity
- environment of space flight and in the readjustment to gravity upon
- returning to Earth. The experiments performed on Columbia's crew and
- on laboratory animals will provide the most detailed and interrelated
- physiological measurements acquired in the space flight environment
- since the Skylab program flights in 1973 and 1974.
- Other payloads on the SLS-1 mission include 12 experiments being flown
- under NASA's Get Away Special program. The experiments, enclosed in
- canisters on a bridge in the Shuttle's cargo bay, will investigate such
- topics as materials science, plant biology and cosmic radiation.
- The mission is planned to last 9 days, 3 hours and 30 minutes,
- concluding with a landing at Edwards Air Force Base, CA. Following
- the STS-40 mission, Columbia will then go to Palmdale, CA, for nearly
- 6 months to undergo major modifications and inspections at Rockwell
- International Corp. Columbia is next scheduled to fly on STS-50, the
- U. S. Microgravity Laboratory mission, in June 1992.
-
- STS-40 CREW BIOGRAPHIES
-
- Marine Corps Col. Bryan D. O'Connor, 44, will serve as Commander
- of STS-40 and will be making his second space flight. O'Connor, from
- Twentynine Palms, CA, was selected as an astronaut in May 1980.
- Air Force Lt. Col. Sidney M. Gutierrez, 39, will serve as Pilot.
- Selected as an astronaut in 1984, Gutierrez, from Albuquerque, NM,
- will be making his first space flight.
- James P. Bagian, M.D., 39, will serve as Mission Specialist 1 (MS1).
- Selected as an astronaut in 1980, Bagian is from Philadelphia, PA, and
- will be making his second space flight.
- Tamara E. Jernigan, Ph.D., 32, will serve as Mission Specialist 2
- (MS2). Selected as an astronaut in 1985, Jernigan is from Santa Fe
- Springs, CA, and will be making her first space flight.
- Margaret Rhea Seddon, M.D., 43, will serve as Mission Specialist 3
- (MS3). Selected as an astronaut in 1978, Seddon is from Murfreesboro,
- TN, and will be making her second space flight.
- Francis Andrew Gaffney, M.D., 44, will serve as Payload Specialist
- 1 (PS1). Gaffney will be making his first space flight and his hometown
- is Carlsbad, NM.
- Millie Hughes-Fulford, Ph.D., 46, will serve as Payload Specialist
- 2 (PS2). Hughes-Fulford, from Mineral Wells, TX, will be making her
- first space flight.
- NASA SPCLNK/BBS
-
-
-
- NEW ASTRONAUT CANDIDATES SOUGHT BY NASA
-
- NASA conducts astronaut candidate selections on a 2-year cycle and
- has scheduled the next class of candidates for July 1992. Interested
- individuals may apply until the cut-off date of July 1, 1991.
- Applications received after the deadline will be eligible for consideration
- in the next selection cycle.
- After a 6-month process including screening of applications, interviews
- and medical evaluations, selections will be announced early in 1992, and
- the new candidates will report to the Johnson Space Center, Houston, in
- July. The limited number of selections to be made every 2 years is based
- on projected requirements.
- There are two types of astronaut candidate positions -- mission specialist
- and pilot. Successful pilot applicants typically have extensive piloting
- experience in high-performance jet aircraft and flight test experience.
- Successful applicants for the mission specialist positions typically have
- significant backgrounds in the sciences (materials science, Earth science,
- medical science and space science) or engineering. This year, because of
- the requirements of some future payloads and experiments, NASA is
- particularly interested in individuals with backgrounds in medical
- sciences research, microgravity research and materials processing. All
- applicants for the Astronaut Candidate Program must be U.S. citizens.
- An application package may be obtained by writing to :
-
- NASA Johnson Space Center
- Attn: AHX Astronaut Selection Office
- Houston, TX 77058
-
- NASA SPCLNK/BBS
-
-
-
- ENDEAVOUR STATE OF THE ART OF SHUTTLES
-
- NASA's newest orbiter features a host of enhanced systems and
- improved or updated components.
- The onboard computing, navigation and guidance system uses newer
- generation inertial measuring units and faster computers. Endeavour
- also features improved nosewheel steering and updated auxiliary power
- units.
- In addition to the systems which Endeavour has in common with its
- orbiter fleet members, OV-105 features a drag chute which is expected
- to decrease the landing distance by more than 1,000 feet.
- Things might be more crowded aboard Endeavour missions, though, as it
- also features 127 cubic feet of additional mid-deck stowage.
- Endeavour also inaugurated another new NASA vehicle, the new 747 shuttle
- carrier aircraft, NASA 911, which joins the first carrier aircraft, NASA
- 905. The new carrier aircraft was used to transport the Endeavour to
- Kennedy Space Center on May 2.
- NASA SPCLNK/BBS
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 4
-
- NASA TO TEST FLIGHT-WEIGHT AERO-SPACE PLANE COMPONENT
-
- NASA is preparing to test a structural component made of advanced
- carbon-carbon composite material as part of the X-30 National Aero-Space
- Plane (NASP) program. Carbon-carbon is an advanced heat-resistant,
- non-metallic material that may be used on the NASP flight research
- vehicles in the mid-1990s.
- The NASP mission profile demands much greater performance from its
- structures and materials than does the Space Shuttle, which travels
- through the atmosphere in a relatively short time. Engineers expect
- that the X-30 will experience structural loads at extreme temperatures
- and sustained high temperatures in high-altitude cruise through the
- atmosphere.
- Design and fabrication of this major NASP flight-weight component
- follows years of technology development. The carbon-carbon material
- is stronger than metal at high temperatures. It's also lighter than
- aluminum, making it a good alternative in areas where active cooling
- can be avoided.
- The component is part of a full-scale wing control surface from a
- generic NASA aerospace plane design. The structure was shipped to NASA's
- Ames-Dryden Flight Research Facility, Edwards, CA, for extensive tests
- to begin this Fall. The flap-like component first will be tested for
- its ability to withstand mechanical loads similar to those on a vehicle
- that takes off from a runway like an airliner and flies into orbit.
- Thermal trials are scheduled to start in Fall 1992. Initial tests will
- be limited to state-of-the-art strain measurement capabilities -- about
- 600 degrees F. Researchers hope to achieve test temperatures exceeding
- 2000 degrees F. by 1993.
- The Missile Division of LTV Corp., Grand Prairie, Texas, designed and
- built the NASP test component under contract to NASA's Langley Research
- Center, Hampton, VA LTV's successful fabrication of the somewhat stiff
- composite represents a major milestone in materials technology development.
- "The fabrication was challenging," said Dr. Wayne Sawyer of Langley's
- Structural Mechanics Division. "It is a big part that requires a series
- of fairly high-temperature thermal cycles in the fabrication process.
- These thermal cycles result in material deformations in some way or
- another. It shrinks and expands and tends to warp. Just being able to
- make a big part or several big parts that will fit together is very tough
- and requires good control of the tolerances and the fabrication process."
- The rib-stiffened NASP component is about 56 inches long, 39 inches
- wide, 14 inches thick at the leading edge and 6 inches thick at the
- trailing edge. It is patterned after part of a flight control surface
- called an elevon, which is mounted at the back of some aircraft and the
- Space Shuttle orbiter to provide pitch and roll control.
- "To our knowledge the component is made of some of the most complicated
- carbon-carbon parts ever fabricated," said Langley's Dr. Don Rummler,
- also of the Structural Mechanics Division. The need for a load-bearing
- tube with multiple layers and many holes and cutouts complicated the
- fabrication task. High-temperature requirements dictated that even
- simple parts like fasteners were made of carbon-carbon.
- Extra care was taken to overcome the potentially serious problem of
- delamination of the materials, which is almost impossible to repair.
- Technicians built up the test structure one thin layer at a time; it has
- 42 layers, or plies, at its maximum thickness.
- The component parts were heated to high temperatures several times and
- densified to increase their strength, in a process Rummler likens to
- "burning toast." Strength went up with each processing cycle, as epoxy-like
- material was used to densify the material by filling tiny voids in the
- carbon matrix between heat treatments. A final coating protected exterior
- surfaces against oxidation.
- Just where, how and if advanced carbon-carbon will be used in the X-30
- has yet to be decided. "The material and the advanced fabrication
- procedures developed to make the elevon structure represent an option that
- we did not have at the beginning of the National Aero-Space Plane program,"
- explained Rummler. "It is a design-efficient, light-weight alternative."
- NASA SPCLNK/BBS
-
-
-
- ASTRO MISSION TO REFLY
-
- NASA announced May 20, that the second Astro mission will fly aboard
- the Space Shuttle. "We are delighted to be able to refly this proven
- scientific performer," said Dr. Lennard A. Fisk, Associate Administrator
- for Space Science and Applications.
- The success of the earlier mission and the demonstrated ability of the
- instruments to acquire high-quality scientific data are among the major
- reasons for reflight of the Astro payload.
- Astro-2, like Astro-1 which flew in December of 1990 aboard Space Shuttle
- Columbia, will be dedicated to a single scientific discipline - astrophysics.
- The following three instruments will fly on Astro-2 and observe energetic
- objects in space in the ultraviolet portion of the electromagnetic spectrum:
-
- o The Hopkins Ultraviolet Telescope (HUT), developed at Johns Hopkins
- University, performs spectroscopy, breaking light into its constituent
- colors, allowing scientists to analyze the chemical composition and
- temperature of the objects HUT observes.
-
- o The Ultraviolet Imaging Telescope (UIT), developed by NASA's Goddard
- Space Flight Center, produces images of especially hot components of
- nebulae, stars and galaxies. These images help to explain the physical
- structure of such objects.
-
- o The Wisconsin Ultraviolet Photopolarimeter Experiment (WUPPE), developed
- at the University of Wisconsin, measures a subtle characteristic of light,
- its polarization. These measurements probe the orientation and detailed
- physics of the distant regions in which the light originates.
-
- Astro-2 complements the much larger Hubble Space Telescope. HUT, for
- example, explores a region of the spectrum immediately adjacent to that
- studied by Hubble. UIT, because of its very large field of view, can serve
- as a "finder" for the powerful imaging devices aboard Hubble. Finally,
- WUPPE's precision polarimetry adds another dimension to the physical
- understanding of astronomical objects obtained from Hubble's collection of
- instruments.
- Astro-2 will be managed by the Marshall Space Flight Center, Huntsville,
- AL, for the Office of Space Science and Applications, NASA Headquarters,
- Washington, D.C.
- NASA SPCLNK/BBS
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 5
-
- GALILEO MISSION STATUS
- May 15, 1991
-
- The Galileo spacecraft is 49.6 million miles from Earth, making the
- round-trip communication time almost 9 minutes. Speed in orbit is 54,526
- mph; distance from the Sun is 143 million miles or 1.54 astronomical units.
- The spacecraft has traveled 919 million of its 2.4-billion-mile looping
- course to Jupiter.
- Galileo is in a stable cruise mode, spinning at about 2.9 Rpm, and
- transmitting engineering data at 1200 bits per second over the low-gain
- antenna. Spacecraft health and performance are good except that the
- high-gain antenna is only partly deployed.
- This week the Galileo spacecraft team began a series of tests to
- characterize this partly-open antenna. Yesterday the spacecraft was
- shifted from all-spin to dual-spin (the aft section fixed in inertial
- space) and back. Celestial and gyro data may reveal a very slight wobble,
- verifying that the antenna opened off-center. It will be a very subtle
- effect because the antenna is light and the spacecraft heavy. Another
- test tomorrow, using radio signals, may give more information on the
- antenna's shape.
- NASA SPCLNK/BBS
-
-
-
- ULYSSES MISSION STATUS
- May 15, 1991
-
- The Ulysses spacecraft remains in good condition as it cruises through
- the ecliptic plane on its way to Jupiter. Today Ulysses is approximately
- 498 million kilometers (309 million miles) from Earth, traveling at a
- heliocentric velocity of approximately 79,200 kilometers per hour (49,300
- miles per hour).
- Following discussions at the spring science working team meeting in
- Heidelberg, Germany, steps were taken to schedule longer, 10-hour passes
- to permit the spacecraft's real-time link to operate at a continuous bit
- rate of 1024 bps even when the onboard tape recorder is being played back.
- A new maneuver strategy has been implemented to maintain the expected data
- rate at baseline levels during the remainder of Ulysses' journey to Jupiter
- and after it exits the ecliptic plane.
- To maintain continuous bit rate links during each extended pass, operations
- team members will perform Earth-pointing maneuvers more frequently to keep
- Ulysses pointed more precisely at the Earth. During this reporting period,
- routine slew maneuvers were performed yesterday, May 14, and were planned
- for tomorrow, May 16, and Monday, May 20.
- NASA SPCLNK/BBS
-
-
-
- GAMMA RAY OBSERVATORY (GRO)
- WEEKLY STATUS REPORT #5
- May 20, 1991
-
- The Flight Operations Team in the Payload Operations Control Center,
- Goddard Space Flight Center, Greenbelt, MD, reports the Gamma Ray
- Observatory (GRO) is performing well. GRO orbits Earth at an altitude of
- 287 x 280 statute miles (462 x 451 kilometers).
- All four of GRO's instruments have been calibrated. Science operations
- began Thursday May 16, 1991 with the observatory pointed toward a pulsar
- in the Crab Nebula. The Phase 1 viewing plan of the science operations
- is a full-sky survey expected to last fifteen months.
- Analysis of the propulsion system pressure transducer and valve
- misconfiguration anomalies continues. The system is stable and the
- observatory will continue to be operated in its present configuration
- for an indefinite period. The propulsion system anomalies do not affect
- the spacecraft's operation. Four detectors in the Imaging Compton
- Telescope (COMPTEL) instrument have not been activated at this time,
- leaving the instrument at 67% of full efficiency. The detectors are
- experiencing high levels of noise associated with out-gassing. Out-gassing
- is a normal process. One of the detectors will be activated this week and
- all four are expected to be activated by the end of May. The Flight
- Operations Team anticipates that COMPTEL will be functioning at 100 percent
- efficiency once the equipment is activated.
- NASA SPCLNK/BBS
-
-
-
- MAGELLAN STATUS REPORT
- May 17, 1991
-
- The Magellan spacecraft, now in its second mapping cycle, went through
- an orbit trim maneuver today so it will not duplicate the first cycle's
- altimeter data. The new altimeter track will interleave with the first
- cycle's track.
- In order to improve the quality of data, it was decided to slightly
- rotate the spacecraft's orbit around the node -- an imaginary line drawn
- through the poles of Venus.
- Mapping was suspended at 6:43 a.m. PDT today in preparation for the
- orbit trim maneuver which began at 11:33 a.m. The burn, using the small
- thrusters, lasted for little more than 33 minutes. The burn shifted the
- orbit about 11 kilometers (6.8 miles).
- The spacecraft also was switched from the high-gain antenna to the
- medium-gain antenna for the operation. Normal mapping is to resume at
- 7:46 p.m.
- The spacecraft and radar system are performing well. Six of the seven
- star calibrations Thursday were fully successful.
- NASA SPCLNK/BBS
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 6
-
- NASA DISCOVERS IMPACT LIKELY TIED TO DINOSAURS' DEMISE
-
- The first surface evidence of a buried impact crater formed by a comet
- or asteroid which may have caused the extinction of the dinosaurs has been
- discovered by NASA researchers.
- The scientists believe a ring of sink holes in the northwestern corner of
- the Mexican state of Yucatan outlines the largest known impact crater on
- Earth. The crater, which is more than 125 miles in diameter, is a prime
- candidate in the search for an impact that may have caused the planet-wide
- extinctions of dinosaurs and other species about 65 million years ago.
- Charles Duller of NASA's Ames Research Center, Mountain View, CA,
- discovered the ring formation in 1987 while searching satellite imagery
- for water sources used by ancient Mayan cities.
- Two other members of the research team -- Dr. Kevin Pope, formerly of
- Ames and now with Geo Eco Arc Research in La Canada, CA and Adriana Ocampo
- of NASA's Jet Propulsion Laboratory, Pasadena, CA -- considered many other
- geological explanations before concluding the formation was caused by a
- buried impact crater.
- "The apparent age, location and size of the proposed Yucatan impact make
- it one of the best candidates for the global catastrophic event, although
- multiple impacts remain a possibility. Regardless, the Yucatan impact alone
- would have had a devastating impact on the climate, animals and plant life
- of the Earth," Pope said.
- Some scientists believe such an impact pushed so much dust and debris
- into the atmosphere that it blocked sunlight, interrupting the growth of
- plants, starving dinosaurs and other animals and freezing much of the Earth.
- The results of the study by Duller, Pope and Ocampo were announced in the
- current issue of Nature magazine.
- The team's findings agree with the work of other scientists who have
- found unusual circular gravity and magnetic patterns and quartz fractured
- by an impact, all suggesting a buried crater in the Yucatan.
- The circular hydro-geological feature, which they named the Cenote Ring
- (cenote is the local Spanish name for sink holes), provides surface evidence
- of the buried crater's precise location and size. It is centered near the
- town of Chicxulub, for which the buried crater is named.
- Duller mapped hundreds of water-filled sink holes which form an almost
- perfect semicircle that marks the crater's buried rim. Fresh water springs
- well up beneath the surface where the Cenote Ring meets the shore line.
- The sink holes are found in clusters at some places along the rim and
- spaced up to a mile apart at others. They average 300 - 500 feet in diameter.
- Duller and Pope determined the half-circle of sink hole and severely
- fractured limestone outside and along the rim area. This conclusion was
- verified through independent hydrogeological research conducted by Dr.
- Luis Marin, now of the University of Mexico, during his work on a doctoral
- thesis under Dr. Eugene Perry at Northern Illinois University.
- "As the buried crater rim settles over millions of years, the rock on
- top slumps and cracks. Underground water flows through the cracks on its
- way to the ocean. As the water is forced around the unfractured rock in
- the center, the flow dissolves the limestone, causing cave-ins that create
- the sink holes," Pope said.
- Pope and Ocampo examined core sample data taken from nearby exploratory
- oil wells and found they geologically date the buried crater's floor at
- Late Cretaceous about 65 million years ago. The crater floor has younger
- Tertiary sediments on top.
- According to the fossil record, more than half of Earth's plant and
- animal species, including the dinosaurs, disappeared about 65 million
- years ago. This abrupt change in evolutionary history occurred between
- the Cretaceous and Tertiary periods in Earth's geologic history and is
- called the Cretaceous-Tertiary (K-T) boundary.
- Unusual amounts of the rare element iridium -- more abundant in comets
- and asteroids than on Earth -- have been found in the K-T boundary in many
- locations worldwide, leading scientists to believe that a large
- extraterrestrial impact caused the planet-wide extinctions.
- Rock and melted glassy fragments, "blown out" by an impact, have been
- found in the Caribbean and Gulf of Mexico region, causing scientists to
- concentrate the search for the suspect crater in this area. Deposits
- and erosion patterns produced by a gigantic tidal wave have been found
- at the K-T boundary in Texas, Mexico and in cores from the Gulf of Mexico.
- "Our research," Duller said, "adds one more piece of evidence to a complex
- and intriguing jigsaw puzzle. Many researchers in different scientific
- fields have contributed to our understanding of the Yucatan impact. Each
- additional piece brings us closer to understanding one of the great
- mysteries in the evolution of life on Earth."
- NASA SPACLNK/BBS
-
-
-
- ASTRONOMY
-
- The Royal Astronomical Society, London, has announced that astronomers
- have proved the existence of a BL Lac object in a galaxy dominated by a
- large flattened disk. Previously, BL Lacerta objects were thought to exist
- only in the center of elliptical galaxies. BL Lac objects produce X-rays,
- radio and visible light energy which are thought to be produced by
- relativistic jets streaming from the active nuclei of elliptical galaxies.
- There are about 40 known BL Lac objects. The Society says the discovery of
- such an object in a non-elliptical galaxy throws doubt into current theories
- about these objects. The discovery was made by Ian McHardy, Southampton
- University, Roberto Abraham and Caroline Crawford, Oxford University, Pat
- Mock and Roland Vanderspeck, Mass. Institute of Tech., and Marie-Helene
- Ulrich, European Southern Observatory. They were using the 4.2 meter
- Herschel Telescope in the Canary Islands.
- NASA SPCLNK/BBS
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 7
-
-
-
-
- MAGELLAN SCIENTISTS STUDY SURFACE OF VENUS
-
-
- Magellan scientists at NASA's Jet Propulsion Laboratory (JPL), Pasadena,
- CA, are studying the surface features on Venus caused by wind in the
- planet's dense atmosphere, says Project Scientist Steve Saunders.
- The movement of dust and sand is an important geological process on
- planets with atmospheres, he said. The surface pressure of Venus' atmosphere
- is 90 times that of Earth's.
- Soviet landers and the U.S. Pioneer probes measured wind speeds near the
- surface of Venus at 2 to 4 miles per hour (1 to 2 meters per second). Based
- on theory and laboratory experiments, that wind speed is very close to the
- speed required to move sand grains on Venus, Saunders said. Accumulations
- of blown sand and dust can blanket large regions and produce visible patterns
- in the Magellan radar images, he stated.
- "The most prominent wind features in the Magellan images of Venus are wind
- streaks," Saunders said. "Streaks form in the lee of topographic obstacles
- by the deposition or removal of sand and dust and can be used as indicators
- of the direction of the most intense winds," he stated.
- Many large impact craters on Venus have nearby wind streaks that may have
- been caused by the violent winds generated during the impact event or that
- may be the result of a slower process of subsequent wind movement of the fine
- impact debris.
- Magellan has mapped more than 78 percent of the planet and by the time the
- primary mission cycle ends May 15, will have mapped about 84 percent, project
- officials said.
- Project Manager Tony Spear said a newly adopted strategy to protect the
- spacecraft from the heat of direct sunlight has been successful in cooling
- the spacecraft. Magellan has been growing warmer as a result of changes in
- the geometry of Venus, Earth and the sun and the time the spacecraft spends
- broadside to the sun. A strategy, called "two-hide" which results in
- slightly shorter imaging swaths, protects the spacecraft by hiding it behind
- the large antenna and by turning the solar panels away for periods of time to
- reduce reflection. The Magellan project is managed by JPL for the Office of
- Space Science and Applications.
- NASA SPCLNK/BBS
-
-
-
-
- MEETING REPORT
- By Myron Moody
-
- Those members attending the April meeting were Mark Hardaway, Angie Berry,
- Myron Moody, Mike Moery, and Diana Hopkins. Visitors included Clay McCormick,
- and our guest speaker was Carolyn Snavely. At the meeting we talked about
- our plans for making some commercials about space technology, and moving the
- meetings to the Kirkpatrick Center. We then discussed putting out flyers at
- computer conventions, airshows, and having a room party at Thundercon. Mark
- then introduced Carolyn as our guest speaker and she told us about her being
- involved in several of the Apollo and Space Shuttle missions and the projects
- that she had her students perform in model rocketry. We then adjourned the
- meeting right after her presentation and gave Carolyn an honorary membership
- into RASA.
-
-
-
-
- CALENDER OF EVENTS
-
- May 19 RASA meeting - 3:30pm South Community Hospital. Guest speaker
- Johnathan Majid.
-
- May 22-27 Tenth Annual International Space Development Conference in
- San Antonio, TX.
-
- May 31;
- June 1,2 THUNDERCON - Central Plaza Hotel, Oklahoma City, OK.
- NO STAR-OKC MEETING THIS SATURDAY!
- NASA Futures in Space panel - Sunday at noon.
-
- June 8 USS-RANGER meeting - 1:00pm Capital Hills Christian Church.
- STAR-OKC meeting - 2:00pm Moore Public Library.
-
- June 14-16 AEROSPACE AMERICA - FAA Mike Monroney Aeronautical Center.
-
- June 23 RASA meeting at the Kirkpatrick Air-Space Museum 3:30pm.
-
- June 29 STAR-OKC/RASA fossil hunt and star watch - Southeastern Oklahoma.
- For more info. call Kevin Hopkins (405)634-1856.
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- PAGE 8
-
-
-
- WHAT IF...
-
- "Imagination is more important
- than knowledge."
- -- Albert Einstein
-
-
- This section of the newsletter is
- devoted to the proposal, the
- hypothetical supposition, or the
- excursion into the realm of fiction.
- Reader's submissions are encouraged.
-
-
-
-
- TERRA TEARDROP
- by T. M. Hardaway
-
- I am sitting in space
- Viewing Terra Teardrop,
- A teardrop from God's face,
- Home of the human race.
-
- Each sunrise, Earth is shinning,
- With its bright beauty blinding,
- Like a smiling lover's face,
- Day - the warmth of her embrace.
-
- I picked up tomorrow,
- Turned it over in my hands,
- All I saw was sorrow
- And empty barren lands.
-
- Where has the World gone?
- Where did your people go?
- Where did the good go wrong?
- Why all the radioactive snow?
-
- I am sitting in space
- Watching the humans race,
- Each consumed with disgust
- at the others' disgrace.
-
- It's already too late,
- You have sealed your fate.
- Instead of mankind,
- All I see is man-hate.
-
- Terra, you are headed for the end of your days.
- You are going to pay for the sins of your ways.
- You're missing out on the part
- Where love begins,
- And just think, you could have had the stars my friends.
-
- O lovely Terra, goodbye,
- Crystal Teardrop from God's eye.
-
-
-
-
-
-
- MAY 1991 KEY DATES
-
- The fifth month of the year has several possible histories for its
- name. One is the word Maia who was the Roman mother of Mercury. The
- other is Maius, which is Latin for 'great'--perhaps referring to the
- great Roman god, Jupiter. To the Anglo-Saxons this was the Tri-Milchi
- month which referred to the idea that cows were supposed to give milk
- three times a day due to their feeding on fresh spring grass. Native
- American names include the planting moon month of the Dakota Sioux and
- the egg-laying moon month of the Chipewayan.
-
- May
- 1 Scott Carpenter, Mercury astronaut born.
- 2 "Preliminary Design of Experimental World Circling
- Spaceship" published. (1946)
- 4 William Herschel reported active volcanoes on the
- moon. (1783)
- 5 Shepard becomes the first American to go into space.
- (1961)
- 6 Transit of Venus. (2012) Plan ahead!
- 8 The astronomer Lalande records a star that unknown
- to him was the planet Neptune. (1795).
- 9 A laser beam is bounced off the moon. (1962)
- 11 Einstein presented his general Theory of Relativity.
- (1916).
- Comet Iras-Arak-Alcock misses Earth by 27 hrs. (1983)
- 14 Truman signs bill establishing Cape Canaveral as the
- site for a rocket testing range. (1949)
- Skylab launched. (1973)
- Full Earth-but you have to be on the moon to see it.
- 15 Kepler writes 3rd law of Planetary Motion. (1618)
- Last Mercury flight. (Cooper,1963)
- 17 First observations of cloud belts on Jupiter. (1630)
- 18 Apollo 10 launched. (1969)
- 24 Carpenter becomes the second American to orbit
- the Earth.(1962).
- The 20,000th manmade object to orbit the Earth
- is launched. (1989).
- 27 Kennedy announced the Apollo goal-The Moon.
- (1961)
- 28 Monkeynauts, Able and Baker flew in space. (1959)
- 29 Solar Eclipse tests Einstein's theory. (1919)
- 30 ESA, the European Space Agency is founded. (1975)
- NASA SPCLNK/BBS
-
-
-
- *********** RASA PROBE VOLUME 2; ISSUE 4 MAY 1991 ***************
- END
- THANK YOU FOR YOUR ATTENTION. LOOK FOR NEXT MONTH'S ISSUE.
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