Headline News Internal Communications Branch (P-2) NASA Headquarters Friday, May 10, 1991 Audio Service: 202 / 755-1788 This is NASA Headline News for Friday, May 10, 1991 . . . NASA yesterday announced the discovery of the first surface evidence of a buried impact crater formed by the impact of the comet or asteroid which may have caused the extinction of the dinosaurs. The discovery was made by Charles Duller, Ames Research Center, and colleagues Kevin Pope, Geo Eco Arc Research, La Canada, and Adriana Ocampo, Jet Propulsion Laboratory. They were searching 1987 satellite imagery of Mexico's Yucatan area for water sources used by ancient Mayan cities and were able to piece together the impact crater evidence from a ring of sink holes. The ring is more than 125 miles in diameter. These findings, published in the current issue of Nature, agree with other geologic and magnetic data suggesting a buried crater. A core sample taken from nearby exploratory oil wells and analyzed by Pope and Ocampo showed the floor of the crater to date back 65 million years -- to the Late Cretaceous period. The boundary between the Late Cretaceous period and the subsequent, Tertiary, period is the location of enriched deposits of iridium, a metal more abundant in comets and asteroids than in Earth's crust. The NASA team also reports that a large impact to the Earth in the vicinity of the Yucatan, close to the equator, would have profoundly affected global climatic conditions. * * * * * * * * * * * * * * * * The STS-40 flight readiness review will be held Monday and Tuesday, May 13 and 14, at the Kennedy Space Center. Currently, Columbia, with the Spacelab Life Sciences habitable module installed inside its payload bay, is sitting on launch pad 39-B and undergoing final closeout preparations. Ordnance installation will begin this weekend. The flight director and astronaut press briefings will be held Tuesday, May 14. On Wednesday, May 15, the mission scientists and program managers will hold the life sciences press briefing. The Tracking and Data Relay Satellite-E , scheduled for launch aboard Atlantis on STS-43, was mated to its Inertial Upper Stage yesterday. That mission is currently slated for launch sometime during July-August this summer. * * * * * * * * * * * * * * * * Launch of the NOAA-D spacecraft is tentatively set for 11:52 am EDT, Tuesday, May 14, aboard an Atlas-E launch vehicle from Vandenberg Air Force Base. The NOAA-D carries five primary instruments, including the Advanced Very High Resolution Radiometer, and is a cooperative program between NASA, the National Oceanic and Atmospheric Administration, the United Kingdom, Canada and France. NOAA-D will be placed into a 522-mile-high orbit inclined 98.7 degrees to the equator. The spacecraft, a General Electric TIROS-N class satellite, will provide day and night environmental data to all of the cooperating partners. * * * * * * * * * * * * * * * * Ames Research Center's education officials were quite busy last month. They hosted a Hubble Space Telescope symposium for 110 Bay Area teachers from six counties; they helped manage the Santa Clara Valley science and engineering fair for the 638 student participants; and they joined others in participating in the Oakland school district's science and technology fair for 1,700 students and teachers. They also visited 75 schools in other areas of California, and in Washington, Montana and Utah; and met with the Oregon state Aerospace Advisory Committee to plan the 1991-1992 teacher- student aerospace programs. * * * * * * * * * * * * * * * * NASA will hold its second annual Symposium on Industrial Involvement and Success in Commercial Space Tuesday, May 14, at the Hotel Washington in downtown Washington. The all-day, one-day conference is sponsored by the Office of Commercial Programs and provides an overview of the agency's commercial space activities. Here's the broadcast schedule for Public Affairs events on NASA Select TV. Note that all events and times may change without notice, and that all times listed are Eastern. Tuesday, 5/14/91 11:52 am NOAA-D launch from Vandenberg Air Force Base. LIVE 2:30 pm STS-40 mission overview press briefing with lead flight director Al Pennington, from Johnson Space Center. LIVE 3:30 pm STS-40 astronaut crew press briefing, from JSC. LIVE Wednesday, 5/15/91 10:00 am STS-40 mission science and life science experiment press briefings from Johnson and Kennedy Space Centers. LIVE 1:15 pm Magellan-at-Venus final status report, from Jet Propulsion Laboratory. Magellan will have completed one full mapping cycle of the planet. LIVE This report is filed daily at noon, Monday through Friday. It is a service of NASA's Office of Public Affairs. The contact is Charles Redmond, 202/453- 8425 or CREDMOND on NASAmail. NASA Select TV is carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees West Longitude, transponder frequency is 3960 megaHertz, audio is offset 6.8 MHz, polarization is vertical.