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

Today's issue status: done

• SSS unusual discovery
• News briefs – meteor news
• Risk monitoring – NEODyS has posted 2004 NL8

Cover: The newest risk monitoring concern, 2004 NL8, is seen here as caught during the discovery confirmation process yesterday morning by Robert Hutsebaut in Belgium using a 0.25m Rent-A-Scope telescope in New Mexico. This is a composite of twelve 20-second exposures stacked for motion of 1.64"/minute toward 69.0°. See below for more about this object's discovery.

Since the inauguration of the Siding Spring Survey (SSS, see news Index) in Australia with NASA funding and Catalina Sky Survey support, this activity has discovered one comet and nine near-Earth asteroids, four of which have Earth minimum orbit intersection distances (MOIDs) of less than 0.05 AU. As reported overnight (“Unusual object,” posted at 0635 UTC), SSS has now discovered 2004 NN8, which is likely to be a comet but is presently being considered by the Minor Planet Center as among the rarest of asteroidal objects, one orbiting the Sun in reverse direction.

Gareth Williams' comments in discovery MPEC 2004-O09 early this morning leave open the possibility that 2004 NN8 could even be on a path headed out of the Solar System. That is so unprecedented for an asteroidal object that, if proven true, most asteroid databases and related software would need upgrading to accept its orbital elements, or might have to handle it as a pseudo-comet.

2004 NN8 was discovered at July 13.54 UT by Gordon Garradd at the SSS 0.5m Uppsala Schmidt Telescope. He followed it for 35 minutes, and, 1.21 hours after that, it was first confirmed by Rob McNaught on the nearby Australian National University 1m telescope. He followed it for three hours, until July 13.74 and, even as he was watching it, the object was posted to the MPC NEO Confirmation Page (NEOCP) at July 13.67.

David Higgins at Hunters Hill Observatory near Canberra, Australia picked up the object at July 14.46, less than 22 hours after discovery. Soon McNaught was back on it, joined by Gordon Garradd who was now at his own Loomberah Observatory in New South Wales, and by John Broughton at Reedy Creek Observatory in southeastern Queensland. McNaught had two observing sessions for the object with the ANU 1m on the 14th and noted to the MPC that day, as recorded in the MPEC: “Object profile not differentiated from that of stars” (i.e., no cometary signs).

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Meteor news:  SpaceWeather.com today had a brief report [now removed] telling of “several observations of magnificent meteors” over Finland yesterday at 2am local time. There was another event during the night of 12-13 July (news thread).

Risk monitoring 17 July

There was no news in the Saturday Daily Orbit Update MPEC related to active risk monitoring, but NEODyS today posted 2004 NL8, which was announced just before midnight UTC in MPEC 2004-O07.

2004 NL8 was found in LINEAR images from the morning of July 11th after “discovery” in LINEAR observations from the morning of July 15th. Confirmation began very early on the 16th with observations from (in time but not necessarily reporting order): Tentlingen Observatory (Switzerland), Fitz-Randolph Observatory (New Jersey), LINEAR (New Mexico), Robert Hutsebaut (telescope in New Mexico, see above), McDonald Observatory (Texas), the Australian National University 1m telescope, and KLENOT in the Czech Republic. The telescopes used for confirmation were 0.76m to 1.06m, except for a 0.3m and 0.25m.