April 2003 Asteroid/Comet News

1 April 2003

Space.com had an April 1st article exploring "What is a Moon? Definition Lags Behind Soaring Satellite Tally." It reports some possible new terms such as "minor," "irregular," and "ring" moons to help better describe the range of objects being discovered. Minor objects, too, can have natural satellites, or can be binary pairs that orbit about a point in space between themselves, and some irregular planetary moons may be captured minor objects.

The 3 April edition of the journal Nature has two articles for purchase about asteroid formation: "Structure and thermal history of the H-chondrite parent asteroid revealed by thermochronometry," by Mario Trieloff et al., and "Planetary science: Of asteroids and onions," by John A. Wood. Space.com had a 2 April summary article, "New Study: Some Asteroids are Like Onions." And, speaking of asteroids with differentiated layers, Science@NASA on 2 April has a picture of 4 Vesta taken from aboard the International Space Station. This month Vesta is in good view for ground-based observers of all experience levels, as Sky & Telescope explained, along with a lot of interesting information.

A new Centaur, 2003 CC22, was announced in MPEC 2003-G16 on 3 April. It was discovered by Scott S. Sheppard et al. on 8 Feb. on Mauna Kea in Hawaii, and also found in Kitt Peak images of 2 and 4 Feb. Its lowly-inclined orbit is calculated to run between 4.20 and 10.79 AU, just barely crossing the orbits of Jupiter (q = 4.95 AU) and Saturn (Q = 10.05 AU).

MPEC 2003-G25 on April 5th announced 2003 GS, rated by the Minor Planet Center as a PHO. This is another object that travels mostly inside Earth's orbit, with initial calculations showing aphelion at 1.088 AU. It was discovered the morning before by Michael Van Ness at LONEOS. The MPEC showed 83 follow-up observations from overnight from 16 professional and amateur observatories in Europe and the U.S.

Cambridge Conference Correspondence for 4 April, posted on the 7th, has the text of a 3 April news item which may be the first public notice in English of a new Main Belt asteroid mission proposal, the Bering Probe, which comes from scientists belonging to several Danish institutes. In January 2003, at the New Trends in Astrodynamics and Applications conference at the University of Maryland, a paper on "The 'Bering' Small Vehicle Asteroid Mission Concept" was scheduled from Rene Michelsen, Anja Andersen, et al. The Technical University of Denmark Measurement & Instrumentation Systems department has an undated Bering introduction page, which says that the "entirely Danish project," to be "launched around 2006 at an estimated cost of $170 millions," is designed to carry a telescope, laser ranging device, magnetometers, and star trackers. With a 40-minute radio delay, the spacecraft will need to operate autonomously.

Cambridge Conference Correspondence for 8 April (and a SpaceRef.com 7 April posting) carried the text of an April 4th letter to NASA from U.S. NEO scientists urging NASA to add a new, exciting, and affordable goal for human spaceflight and the use of the space station. This is the inclusion of "mitigation" or "NEO deflection studies" (i.e., how to prepare for a comet or asteroid that is found on an Earth-threatening path), as one of NASA's primary goals. . .  [We] propose a new goal for human and robotic space flight: Show how humans and robots can work together on small objects in near-Earth interplanetary space. Space.com had an article about this on the 9th.

It was announced April 9th that "This week NASA gave The Johns Hopkins University Applied Physics Laboratory [JHU/APL], Southwest Research Institute [SwRI] and their partners the go-ahead to start full development of the first mission to Pluto and the Kuiper Belt . . . to go forward with spacecraft and ground system construction," as explained in separate news releases from APL and SwRI. UPI ran a 9 April story quoting APL's Thomas Coughlin: "We're ready to start cutting metal." And Astronomy.com had a 12 April article. For more info about the mission, which is scheduled for launch in 2006, see A/CC's New Horizons and Pluto/Charon archives.

A BBC 10 April article, "Voyage to the asteroid belt," tells about a new Main Belt mission proposal named Apies (Asteroid Population Investigation and Exploration Swarm), for which ESA "has given the go-ahead for a feasibility study" led by Astrium. It would reportedly involve "30 or more" micro-spacecraft powered by conventional rockets or solar sails.

UPI had a 12 April article about "Space stations built by radio," telling about Narayanan Komerath's concept of using radio waves as force fields to someday build "sanctuaries against the deadly radiation storms of interplanetary space assembled from tens of thousands of tons of extraterrestrial rubble." See also A/CC's earlier report, "Reconstituting pulverized asteroids."

Ball Aerospace in a news release dated 14 April announced that NASA has selected it to be a member of the team assembling the proposal for the Widefield Infrared Survey Explorer (WISE), with responsibility for building and operating the spacecraft. If the proposal is accepted next year, the mission could launch in 2008. Among other goals are asteroid observations, to "provide a vast database of new astrometric and radiometric information on [known and] previously unknown [Main Belt] asteroids . . . larger than 3 km." And, "WISE will always be scanning 90° away from the Sun and thus will be quite good at detecting near Earth objects." 200m objects will be "easily detectable" at 1 AU from Earth.
      The WISE mission was previously called the Next Generation Sky Survey (NGSS), and missed being accepted in the 1999 round of NASA Mid-Explorer mission selections, but was picked up this year (see NASA's 20 March 2003 news release). It should not be confused with a Small Explorer mission, the Wide-field Infrared Explorer (WIRE), which launched in 1999 and failed to achieve its infrared science goal.

This was posted to the JPL home page between 16 and 20 April:

Changing of the Guard
Palomar's Oschin Telescope recently underwent an astronomical changing of the guard. On April 16, JPL's Near Earth Asteroid Tracking camera was removed from the 1.2-meter (48-inch) telescope located near San Diego. It will be replaced by Yale University's Quest camera. Since its installation in 2001, JPL's asteroid tracking camera discovered 189 near-Earth asteroids, 19 comets and 14 'Centaurs' (minor planets orbiting between Jupiter and Neptune).

An April 22nd at the University of Maryland Diamondback student newspaper talks about cost, scheduling, and technical difficulties with the coming Deep Impact comet mission, planned to launch in late December next year or early January.

A University of Arizona news release reports that 23 April 2003 was the 80th anniversary of the formal dedication of the Steward Observatory's 0.9-meter telescope, an event attended by the then Vice President of the United States, Calvin Coolidge. The telescope was moved in 1962 to Kitt Peak from its original location in Tucson, Arizona, and in 1982 it was turned over to Spacewatch, which used it to discover many NEOs while pioneering the computer-aided CCD sky scanning process used by today's large NEO programs. Spacewatch built a larger telescope, the 1.8m, which began service in 2001. Then, a year ago today, the 0.9m was taken out of action for overhaul, getting a new CCD mosaic and primary mirror. Its return to duty was marked by the announcements of its first NEO discovery on March 10th, and of its first PHO discovery on May 9th, 2003 JC13.

The Sloan Digital Sky Survey (SDSS) Moving Object Catalog was updated on April 24th in its second release, which lists "astrometric and photometric data for 134,335 moving objects observed prior to March 11, 2003. The catalog also includes orbital elements for 26,847 previously known objects. . .  Objects from the first release are included in the second release because the photometric pipeline and flatfield vectors changed a bit between the two releases."

Sky & Telescope has an article about the upcoming occultation of a star in the constellation Cancer by Main Belt asteroid 74 Galatea. Observing such events is an important worldwide activity, carried out mostly by amateurs, that can lead to information about an asteroid's size and shape, and even whether it may be a binary object. An observer in the path of a predicted star shadow uses a telescope and camcorder to carefully time the duration of the stellar eclipse. Predictions of time and path are posted at various sites, such as one for Galatea for 16 May, which is a link from the Western Hemisphere page of the International Occultation Timing Association (IOTA).
      Each successful observation results in a "chord" that, combined with other chords, yields a shadow shape that represents the asteroid's profile. Unsuccessful and "grazing" observations are needed, too, to help determine the profile's full extent. A beautifully illustrated example of the effort and the results can be seen as a special report on the euraster.net site about an exceptional campaign in Europe last September to observe a stellar occultation by 345 Tercidina.
      Good places to begin learning about participating include Paul Maley's how-to page, and a primer from David Dunham.

The coming week's issue of Newsweek had an article posted 27 April on MSNBC about the mostly quiet efforts of several dot.com entrepreneurs to invest their fortunes in new space businesses. While the focus is on human flight and space tourism, increased public interest and lower-cost access to space, when it comes, will also help boost low-budget missions to minor objects. Space.com on 16 April told about SpaceX, noted in the Newsweek piece as maybe the most promising effort. See also articles about SpaceX 22 April on Wired News and 15 April at USA Today.

The new Planetary Science Research Discoveries article, "Asteroidal Lava Flows," posted April 28th, tells how researchers believe they "may have pieces of lava flows from five different asteroids," including 4 Vesta and another body of similar size that hasn't been identified and may no longer exist.

The Meteoritical Society posted a news item 29 April about allocating particle samples when returned from 81P/Wild 2 by the Stardust mission. A workshop on the nature of interplanetary and interstellar dust will be held in August (see A/CC's Calendar item) as the first of a series, with another next year about extracting particles from the aerogel collecting medium.

Space.com had an article April 30th, "'Shocking' Experiment Reveals How Asteroids Explode," summarizing an article on "Interplanetary dust from the explosive dispersal of hydrated asteroids by impacts" in the May 1st edition of the journal Nature. Researchers Kazushige Tomeoka et al. conclude from physical testing of meteorite samples that "Hydrous material shatters over a much broader pressure range than anhydrous, suggesting that collisions between asteroids produce a preponderance of hydrated material in the interplanetary dust."

Dark-Sky Week – 1-8 April 2003

The week of 1-8 April was designated National Dark-Sky Week in the U.S., as announced 8 Jan. by the International Dark-Sky Association with facts and illustrations. Space.com had articles 21 March and 27 March about the issue of light pollution. UPI put a story on the wires 29 March. And Sky and Telescope had a 1 April article and an interview with activist Jennifer Barlow.
      The British Astronomical Association announced 9 May 2003 that it has joined in launching a national light pollution campaign. BBC has a report.

With the Space Infrared Telescope Facility (SIRTF) launch planned for mid-April, there were news releases April 3rd from Ball Aerospace (with pictures) and the University of Minnesota about their participation in the mission.
      NASA/KSC issued a news release on 9 April detailing events leading up to an 18 April takeoff. And the University of Arizona put out a news release 7 April about the Steward Observatory team that built SIRTF's far-infrared camera.
      Spaceflight Now reported 10 April that the SIRTF launch would be delayed "because of questions raised about the strap-on solid rocket motors" on what will be the first flight of the Boeing "Delta 2 Heavy" launcher. UPI had a confirming article the next day, quoting a NASA spokesperson, and finally the mission site posted a note on the 11th that "launch has been re-scheduled for no earlier than April 26. NASA has decided to use the additional week to complete internal readiness assessments."
      An AFP article about the launch delay ran at SpaceDaily on the 14th, and Florida Today had an article the same day.
      Kennedy Space Center has an ELV Countdown page dedicated to the coming SIRTF launch, which on the 14th was shown as scheduled for very early on 27 April. This page also has links to processing notes and status reports detailing the spacecraft and expendable launch vehicle (ELV) preparations.
      The European Space Agency (ESA) posted a news release 16 April celebrating "Space infrared astronomy comes of age," noting past and future missions. The second such mission, ESA's Infrared Space Observatory (ISO), operated during 1995-98 and led to results such as heralded by an ESA news release, "New study reveals twice as many [Main Belt] asteroids as previously believed" (see A/CC news links). An ESA news release of 17 Feb. 1999, about the naming of an asteroid for ISO astronomer Thomas Mueller, included this poetic thought from Mueller: If our eyes were able to see in the infrared, and of course if we could get rid of the Earth's atmosphere which is opaque to most infrared radiation, we would see hundreds of asteroids sparkling and very few stars.
      On Friday the 18th, the Kennedy Space Center ELV Countdown page for the SIRTF launch gave the launch date as "August 2003." Spaceflight Now reported that the nozzles of the launch vehicle's strap-on solid-rocket boosters were suspect, and there wasn't time to make a necessary change before the launch pad was needed to prepare for the time-critical launch of the second of NASA's two Mars Exploration Rover missions (MER-B), which, by the way, also uses the Delta 2 Heavy launcher with the same new model of strap-on.
      NASA headquarters issued a news release on 18 April with the official word about delaying the SIRTF launch "until no earlier than mid-August 2003." Florida Today had an article on 19 April about the delay, carried also by Space.com on 20 April. Spaceflight Now had a 5 May report about disassembling the mission. The launch is now scheduled for Aug. 23rd.
      For more about SIRTF, see A/CC December and March news links.

The UK/Ireland National Astronomy Meeting (NAM) held during 7-11 April in Dublin, Ireland, had these Royal Astronomical Society (RAS) news releases and related links:

• "Life and Death From Space," 4 April – "five experts in the study of asteroids, comets and impacts will [explain] their ideas about the effects on the Earth and other planets of bombardment by extraterrestrial objects."
• "Reaching for the Asteroids," 1 April – presentation by Apostolos Christou – "scientists are already looking ahead and trying to identify the nearest objects whose resources may be exploited by future entrepreneurs . . .  1999 AO10 requires less energy to achieve a rendezvous than placing an orbiter around the Moon [and four others] are easier to reach than Mars or Venus"
  • Christou & Jonathan McAuliffe's Interplanetary Trajectories page
• "A UK Flotilla to Study Earth-Grazing Asteroids," 1 April – about the Open University and QinetiQ's Simone (SmallSat Intercept Missions to Objects Near Earth) low-budget NEO mission proposal to ESA
  • "Voyage to the asteroid belt," 10 April BBC article – the second half is about Simone, to which ESA "has not yet committed major funds"
  • Open University Simone page
  • QinetiQ 17 Feb. 2003 news release, "QinetiQ to go to 'asteroids near you' soon"
  • ESA Near Earth Objects Space Mission Preparation page with links to each of six proposals, including Simone
  • Tumbling Stone 24 March edition with articles about the six ESA NEO proposals (including Simone) & funding issues
  • Space.com 28 May article about the Simone proposal, which could launch in 2008 if it gets funding
  • more A/CC news links about ESA NEO mission studies

CHFT: The National Research Council of Canada had a news release April 8th, "National Research Council's engineers help build the biggest astronomical camera in the world," and BBC had a report April 11th. They tell about upgrading the 3.6m Canada-France-Hawaii Telescope (CFHT) on Mauna Kea with a new camera that combines 40 CCDs (a "CCD mosaic") to take images made up of 324 million pixels. BBC: "It has an unusually large field of view of one square degree, the size of four full Moons," and has already been used to look at near-Earth objects. "It has also started the CFHT Legacy Survey which will comprise 500 nights over the next five years for studying the Kuiper Belt and the large scale structures of the Universe." The camera manufacturing facility in France has a MegaCam page with technical details, and see CFHT's MegaPrime page for more details.
      LSST: The National Optical Astronomy Observatory (NOAO) in a 24 April news release (also available from the University of Arizona) announced "New Corporation Organized to Develop Ambitious Survey Telescope," about the formation and first meeting on 16 April of the Large Synoptic Survey Telescope Corporation, Inc. (LSST). First light could be "as early as 2011. No site has yet been selected." The design calls for an eight-meter mirror and a camera with two billion pixels, and is expected to be especially good at detecting near-Earth asteroids and trans-Neptunian objects, among other tasks.
      Update:  See a July 30th Space.com article, which reports that the LSST "is expected to go online by 2011" and the "location will be decided in upcoming months."
      In the works: Two new wide-field telescopes are planned to come into operation during 2004-2006 at Paranal in Chile — the ESO 2.6m VLT Survey Telescope (VST) and the UK 4m Visible & Infrared Survey Telescope for Astronomy (VISTA). And there is a Hawaii-based wide-field survey project that is planned to use four 1.8m telescopes with a billion pixels apiece. This Panoramic Survey Telescope And Rapid Response System (Pan-STARRS), was originally called the Panoramic Optical Imager (POI). It is designed specifically to find and follow potentially hazardous objects down to a limiting magnitude of 24, and will have pixel charge shifting to better photograph dim fast-moving objects.

Potentially hazardous asteroids removed from the NEODyS and/or JPL risk pages during April 2003: 1994 UG, 2002 PN & 2003 HA