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Март 1998


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    Архив RU.SPACE.NEWS за 31 марта 1998

    Дата: 31 марта 1998 (1998-03-31) От: Alexander Bondugin Тема: Today On Galileo - March 30, 1998 Привет всем! Вот, свалилось из Internet... TODAY ON GALILEO Monday, March 30, 1998 Encounter activities conclude this evening, just after 6:00 pm, Pacific Time. Shortly thereafter, the spacecraft begins processing and transmission to Earth pictures and science information acquired and stored on Galileo's onboard tape recorder during the last few days. The first items on the processing and transmission schedule are the pictures of Io's north and south poles taken on Saturday. Early in the morning, flight team members transmit to the spacecraft the set of computer commands that will control most of its activity until the next encounter period in late May. Today's flight path takes the spacecraft past the closest approach point to the last Galilean satellite for this orbit, Callisto, at 8:20 pm and a distance of 205,000 kilometers (128,000 miles). The final observation of Europa for this encounter is performed this morning by the Near Infrared Mapping Spectrometer (NIMS). This global observation is the last in a set of three distant observations performed by NIMS this orbit. Io returns to the observing schedule today with a joint observation performed by the Ultraviolet Spectrometer and Extreme Ultraviolet Spectrometer as they gather information on Io's plasma torus. The plasma torus is the donut shaped cloud of neutral and ionized gases that is found along Io's orbit. It is believed to be sustained by all of the material that is ejected from Io by way of volcanic eruptions. This observation will allow scientists to keep tabs on and continue to map the activity levels within the torus. Two observations of Jupiter are performed during today's science gathering. Both are performed in 'real-time', indicating that the data is almost immediately packaged and transmitted to Earth and not stored on the spacecraft's tape recorder for later processing. Both are performed by the NIMS instrument. The first looks at aurora near Jupiter's north pole while the second gathers more information on the makeup and temperatures of Jupiter's atmosphere. A look at Callisto rounds out the remote sensing observation schedule for this encounter period. Performed jointly by the NIMS instrument and the Ultraviolet Spectrometer (UVS), the global observation will provide more information on the surface properties of this moon. A similar observation will be performed on the Callisto orbit in May 1999. The end of the encounter period also concludes the fields and particles instruments' survey of Jupiter's magnetic and electric field environment. This survey is planned to be repeated each and every encounter and will provide an orbit-to-orbit record of the activity levels within this environment. Come back tomorrow for the return of This Week on Galileo as the Galileo spacecraft continues its exciting journey of discovery! For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page: http://www.jpl.nasa.gov/galileo/ Hа сегодня все, пока! =SANA=
    Дата: 31 марта 1998 (1998-03-31) От: Alexander Bondugin Тема: Mars Global Surveyor Update - March 27, 1998 Привет всем! Вот, свалилось из Internet... Mars Surveyor Operation Project Report Glenn Cunningham Mars Global Surveyor Project Manager March 27, 1998 2:00 PM PST Early in the morning of March 27th, Mars Global Surveyor executed a 4.43 m/s bi-propellant main engine burn at the apoapsis of its 201th orbit of Mars to raise its orbit's periapsis from 123 km to 170 km and effectively terminate the first phase of aerobraking. MGS will remain in this 11.6-hour duration orbit until early September 1998, when aerobraking operations will be undertaken again, further reducing the orbit period to the 2-hour, circular, sun synchronous mapping configuration. The spacecraft was configured for this science phasing orbit period and the science instruments were turned on again later Friday morning. During the five month period without aerobraking, MGS will return to taking science data with all its instruments. At each periapsis passage, Mars Orbiter Camera images and Mars Orbiter Laser Altimeter measurements will be taken. Magnetometer/Electron Reflectometer and Thermal Emission Spectrometer data will be taken all through the orbit period. Radio science data will be taken at every opportunity. X and Ka-Band propagation data will be acquired as the spacecraft approaches solar conjunction during May. During April, MGS will have the opportunity to perform some "targeted" imaging of the Mars Pathfinder and Viking landing sites, as well as the Cydonia region. There will be three opportunities on eight day centers to image each of the sites during April. According to our previously announced process for imaging Cydonia, the Project has announced the opportunities (press release on March 26th), and will announce the detailed times of image acquisition and release early next week when updated orbit data is available. The MGS spacecraft continues in excellent health. Hа сегодня все, пока! =SANA=
    Дата: 31 марта 1998 (1998-03-31) От: Alexander Bondugin Тема: Physics News Update - March 27, 1998 Привет всем! Вот, свалилось из Internet... PHYSICS NEWS UPDATE The American Institute of Physics Bulletin of Physics News Number 364 March 27, 1998 by Phillip F. Schewe and Ben Stein THE FLATTEST SURFACE IN THE SOLAR SYSTEM is on Mars' northern lowlands. Over a 2000-km-around belt between 50 and 80 degrees north latitude, the surface tilts up only about 0.05 degrees to the south. This data and a number of other results from the Mars Global Surveyor---such as information on the Martian atmosphere, magnetism, plasma fields, topography, and mineralogy---are reported in the 13 March issue of Science. WEIRD BEHAVIOR IN QUANTUM DOTS. Interesting things happen when particles are confined in a tiny box. Researchers at MIT led by Raymond Ashoori (617-253-5585) make themselves such a box, a quantum dot, out of semiconductors---a layer of gallium arsenide between layers of aluminum gallium arsenide. On top of this sandwich sits a metal gate electrode which attracts electrons into the dot and controls the arrival or departure of electrons one at a time. Building up from just one electron, the MIT physicists collect a puddle of electrons and observe how the arrival of each newcomer must overcome (with the help of an increasing gate voltage) the mutual repulsion ("Coulomb blockade") of those already in place. For small dots (0.2 microns across) a graph of charge-vs-voltage would look like a staircase. Such an effect is at the heart of single-electron transistors (SET), which act as sensitive detectors of electrical charge (just as superconducting quantum interference devices---SQUIDS--- are sensitive detectors of magnetic flux). For larger dots (0.5-1.2 microns across), containing fewer than several hundred electrons, the MIT scientists were astonished to observe an unexpected and mysterious pairing: for each stepwise voltage increase not one but two electrons were able to join the puddle. The pairing has not yet been explained but the data strongly suggest that it arises from a novel quantum effect that develops whenever electrons are localized into spatially isolated regions within the dots. For medium-sized dots (0.5 microns) the physics gets even weirder: the pairing occurs only for every fourth or fifth electron. The goal now is to understand the underlying pairing mechanism. (Talk at the last week's APS meeting in Los Angeles.) ENERGETIC COSMIC RAYS MAY BE IRON NUCLEI. Cosmic rays are particles that come from far away (many likely to be of extra-galactic origin) and strike our atmosphere, where they engender a shower of new particles that show up in detectors on the ground. One of the biggest puzzles in cosmic ray physics is why there should be so many events with total energies above 100 EeV (10^20 eV). The main reason for this was the notion that if the primary particle were journeying from a distant galaxy, the particle's energy would be sapped by interactions with cosmic microwave background photons or with infrared background radiation (IBR). There is the additional problem of how cosmic rays with energies as high as 300 EeV could have been accelerated to such a degree if the first place (see Update 243). Floyd Stecker of the Goddard Space Flight Center has determined that a 200 EeV nucleus (starting out as an iron nucleus) could negotiate a 300-light- year journey through the IBR. The nucleus would partially disintegrate en route, but would still arrive at Earth with a potent energy. (Physical Review Letters, 2 March.) Hа сегодня все, пока! =SANA=
    Дата: 31 марта 1998 (1998-03-31) От: Alexander Bondugin Тема: WDC-A R&S Launch Announcement 12928: Iridium 55, and 57-60 Привет всем! Вот, свалилось из Internet... COSPAR/ISES WORLD WARNING AGENCY FOR SATELLITES WORLD DATA CENTER-A FOR R & S, NASA/GSFC CODE 633, GREENBELT, MARYLAND, 20771. USA SPACEWARN 12928 COSPAR/WWAS USSPACECOM NUMBER SPACECRAFT INTERNATIONAL ID (CATALOG NUMBER) LAUNCH DATE,UT IRIDIUM 55 1998-019A 25272 30 MARCH 1998 IRIDIUM 57 1998-019B 25273 30 MARCH 1998 IRIDIUM 58 1998-019C 25274 30 MARCH 1998 IRIDIUM 59 1998-019D 25275 30 MARCH 1988 IRIDIUM 60 1998-019E 25276 30 MARCH 1988 ..JOSEPH H. KING, DIRECTOR, WDC-A-R&S. [PH: (301) 286 7355. E-MAIL: KING@NSSDCA.GSFC.NASA.GOV 30 MARCH 1998, 19:00 UT] Dr. Edwin V. Bell, II _/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ Mail Code 633 _/_/ _/ _/ _/ _/ _/ _/ _/ NASA Goddard Space _/ _/ _/ _/_/ _/_/ _/ _/ _/ Flight Center _/ _/_/ _/ _/ _/ _/ _/ _/ Greenbelt, MD 20771 _/ _/ _/_/_/ _/_/_/ _/_/_/ _/_/ +1-301-286-1187 ed.bell@gsfc.nasa.gov NSSDC home page: http://nssdc.gsfc.nasa.gov/ Hа сегодня все, пока! =SANA=
    Дата: 31 марта 1998 (1998-03-31) От: Alexander Bondugin Тема: Announcing Cassini & Galileo Educators' Workshops Привет всем! Вот, свалилось из Internet... Announcing 2 JPL Educators' Workshops: Workshop 1 - Cassini: On the Way to Saturn Workshop 2 - Europa: An Ocean in Space? Dear Educator, You and members of your staff are invited to attend one or both of the upcoming free Workshops at NASA's Jet Propulsion Laboratory in Pasadena, California for math and science educators of grades 5 through 12. * Workshop 1 - On Saturday April 25, 1998, from 9:00 a.m. to 4:00 p.m, features the Cassini-Huygens Mission and its exploration of the planet Saturn. Launched on October 15, the Cassini-Huygens spacecraft is now approaching the first of four planetary swingbys that will ultimately lead to its arrival and insertion into orbit around Saturn in 2004. The Cassini Program is offering a Workshop one day before the spacecraft's gravity assist at Venus. Scientists and engineers associated with the program will discuss the spacecraft, mission, and science. Activities planned for the Venus flyby will be described and there will be a discussion of our current understanding of Venus. Educational materials developed by the program will also be described. * Workshop 2 - On Tuesday, May 5, 1998, you can learn about the intrigue of Jupiter's moon Europa, which might have an ocean underneath its icy surface. Science experts and educators will provide an overview of the interest in Jupiter's moon Europa, which is thought to have had an ocean of water underneath its icy surface at some time in recent geologic history, and may still today. Come for an update on the exploration and understanding of this intriguing moon, and leave with demonstrated activities you can use in your classroom. Because space is limited, pre-registration is required and is limited to five teachers per school. To register for either Workshop, complete the enclosed form and return it according to the instructions. Applicants will be accepted separately on a first-come, first-served basis until each event is full. Past events have been extremely popular, filling before the due date, so we anticipate that these will also fill very quickly. We will mail responses to all registrations we receive by April 10, informing the applicant whether he/shehas been accepted to either Workshop. Those who are accepted will receive a confirmation letter for the requested Workshop(s) (which is required for admission to the Workshop) and directions to JPL. Please note: This event is intended for educators only; space for students and family members is not available. We ask that you register only if you are able to attend the entire event. If you receive this letter but are an educator of grades other than 5-12, you may attend the Workshop, but please keep in mind that the material presented may not be suitable for use in your classroom. The enclosed announcement contains information about a separate event, celebration of the exploration of Europa (May 20-21). Don't forget JPL's Annual Open House (May 30-31). These events are open to the public and do not require registration. Please feel free to share them with family, friends, and students. If you have any questions, please call (818) 393-JOVE (5683), email us at events@galileo.jpl.nasa.gov or for Cassini, at Cassini@pop.jpl.nasa.gov., or visit our World-Wide Web site at http://www.jpl.nasa.gov/galileo or http://www. jpl.nasa.gov/cassini. We look forward to seeing you at JPL! Sincerely, Cassini and Galileo Educational Outreach Teams Please respond by April 13, 1997 ________________________________________________________________________ Registration instructions: 1. Complete the following form -- one person per form. Don't forget your ZIP code. 2. Submit it by fax to: (818) 354-6256 or by mail to: Educators' Workshops c/o Valerie Pickett JPL MS 264-419 Pasadena, CA 91109-8099 3. If you FAX your form and then also mail it, please attach a sticky note or write in colored ink the following message: "This form was faxed on _________ (date)." 4. If you have questions about your registration, please call (818) 393-5683. We will do our best to get back to you within 2 business days. Please understand that we are unable to respond to incomplete forms, forms mailed to the wrong address, forms that get lost in the mail, forms eaten by the family pet, etc., etc. ________________________________________________________________________ Please indicate which Workshop for which you are registering: [ ] April 25, 1998 - Cassini: On the Way to Saturn [ ] May 5, 1998 - Europa: An Ocean in Space? Name _______________________________________________________________ Subject(s) you teach __________________________ Grade Level(s) _____________ School/Organization____________________________________________________ [ ] Home address Address________________________________________________ [ ] School address City/State ______________________________________ ZIP_________________ Daytime Phone______________________ Evening Phone______________________ Email address: _________________________________________________________ Are you able to attend the entire Workshop? [ ] Yes [ ] No Did you attend the September 20 or 21, 1997 Cassini Educators' Workshop? [ ] Yes [ ] No Did you attend the December 2, 1997 Galileo Educators' Workshop? [ ] Yes [ ] No Have you attended any other JPL Educators' Workshop? [ ] Yes [ ] No If you have attended previous Workshops, in what ways have they been helpful? _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ In what ways could they have been more helpful? _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ How did what you learned at the Workshop(s) impact your students? _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ Are there any specific questions you want to see addressed at the Workshop? _______________________________________________________________________ _______________________________________________________________________ _______________________________________________________________________ Hа сегодня все, пока! =SANA=

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