The Asteroid/Comet Connection's
daily news journal about
asteroids, comets, and meteors

Today's issue status: done, updated 2x

• News briefs – Raptor & meteor news
• Risk monitoring

Cover: A meteor crosses the Milky Way over Cerro Paranal in Chile just before midnight UT of 25 August 2002 in this 90-second exposure from the Mini All-Sky Cloud Observation Tool (MASCOT), a fisheye camera used to help run the Very Large Telescopes (VLTs). North is up and, unlike the original 183Kb JPEG, east is left. This image is part of a European Southern Observatory news release today about a different meteor caught by VLT spectrograph (see below).
      More info: Sylvain Rondi explains the MASCOT camera in French, has some images, and gives links to the Audela control freeware, to TASCA — an all-sky camera project at Cerro Tololo in Chile, and to the CONCAM all-sky camera network that includes the Canaries, Kitt Peak, Mauna Kea, and Siding Spring, but isn't especially suited to recording meteors.

Raptor:  An item reposted on Science Blog yesterday brought to A/CC's attention an article in the Los Alamos National Lab (LANL) Fall 2003 Research Quarterly and December 2003 U.S. Department of Energy Research News (only LANL's copy has photos and sidebars). It tells about Raptor (RAPid Telescope for Optical Response), a project something like SuperWASP on La Palma (Index).

Raptor consists of four robotic observatories, one at LANL in Los Alamos, New Mexico and the others together at Fenton Hill Observatory west of Los Alamos. Two identical units (A and B) separated by 38 miles (61 km.) provide stereovision and a cross-check for false positives. Of the other units at Fenton Hill, one searches for extrasolar planets and “catalogs known celestial objects to help identify transient optical events,” and one measures event colors.

A photo of Raptor-A at Fenton Hill shows an array of four 85mm telephoto lenses for widefield surveying (to 13th magnitude) and one 400mm lens to make “close-up” movies (17th magnitude) when an event has been locked onto.

The stereo capability measures distance to closer transient events, such as meteors, satellites, space debris, near-Earth objects, and airplanes. One LANL sidebar on “Detecting

Killer Asteroids” tells readers:

“ Measuring an asteroid's parallax has an advantage over the current detection method, which looks for the streak an asteroid leaves in a time exposure of the night sky. . .  But the asteroids of most concern are headed straight for Earth and thus leave no streaks. Fortunately, a parallax measurement can easily detect such objects [and] RAPTOR's stereovision . . . can detect such asteroids as far away as the moon [that] would strike Earth in 8 hours. . .  Replacing RAPTOR's current telescopes with an array of 1-meter telescopes, however, would enable RAPTOR to provide advanced warning of a week or more. ”

Raptor doesn't have an IAU MPC observatory code, although MPC#439 is assigned to a former Los Alamos test installation (no NEAs reported) of a related project, the Robotic Optical Transient Search Experiment (ROTSE). (An earlier ROTSE incarnation at Los Alamos recorded a spectacular half-hour meteor breakup and trail sequence of a 1998 Leonid that was also caught by an all-sky camera.)

Meteor news:  A European Southern Observatory news release today tells about a meteor that happened to cross a Cerro Paranal 8m VLT spectrograph slit at magnitude -8 during a supernova observation in May 2002. Beside the “telltale meteor emissions of oxygen and nitrogen atoms

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<< meteor news continued from panel 1

and nitrogen molecules. The VLT spectrum was the first to reveal the far red range where carbon emission lines are predicted; the absence of the lines puts constraints on the role of atmospheric chemistry when life started on earth.”

There are reports today at BBC and PhysicsWeb about news yesterday on the history and place of origin of lunar meteorite SaU 169. And Astronomy.com has an article from yesterday about the correlation of the Chesapeake Bay and Popigai impacts (see “Bits & pieces” July 26th). It notes that three other impacts also have “roughly similar” datings: “Mistastin (38 million years old) and Wanapitei (35 million years), both in Canada, and Logoisk in Belarus (40 million years).”

Images and movies have been posted temporarily at Sandia National Lab from its all-sky camera in Albuquerque, New Mexico, a bright meteor low on the south-southwestern horizon from 2:07am yesterday (JPEG, 612Kb movie), and a dawn meteor in the northeast with a short trail at 5:38am today (JPEG, 510Kb movie). North is up and west is left in this imagery, and the movies are QuickTime files.

Correction: There were two Sandia meteors the morning of the 29th. The other was at 12:58am MDT above the western horizon (JPEG, 536Kb movie).

Risk monitoring 30 July

The Friday Daily Orbit Update MPEC (DOU) has observation of 2004 OT11 yesterday morning from Francisquito Observatory in southern California, last night from Eschenberg and Naef observatories in Switzerland, and early today from Wildberg Observatory in Germany. Today's DOU also carries three positions for 2004 OT11 from Bergisch Gladbach Observatory in Germany spanning midnight 27-28 July, two of which are earlier than the first confirmation observations in the July 28th discovery MPEC (going strictly by observation times rather than by the order in which the Minor Planet Center actually received the observations).

Today NEODyS and JPL significantly cut their impact solution counts for 2004 OT11 (JPL by more than half) while slightly raising their overall risk assessments.

The DOU has a set of positions reported for 2004 NL8 from Naef Observatory from last night. Today NEODyS slightly lowered its risk assessment for this kilometer-size object, and is now showing two impact solutions instead of one.