The Asteroid/Comet Connection's
daily news journal about
asteroids, comets, and meteors
Today's issue status: done
Details: 2003 Mar 02 21:01:45-03:46 UT. Mag R=17.3. 0.0040 AU from Earth (1.5 lunar distance). 0.30m f/6.3 Schmidt-Cassegrain+CCD. 9x2s, binned 2x2, unfiltered. 14s gap between images, stacked for motion of 151 arcsec/min in PA 252°. Field 17x13 arcmin, N up. P Birtwhistle (J95).
|Distant big object – part 1/1||Major News for 14 March 2004|
Distant big object
The Australian at around 1430 UTC today posted an article dated tomorrow telling that "NASA is expected to announce today" that "scientists have found a new world orbiting the solar system — more than 3 billion kilometres further away from the Sun than Pluto." The Times of India followed about half an hour later with a shorter article, and an Internet mailing list this morning has a message telling about finding a related and publicly available Hubble Space Telescope (HST) proposal. In fact, that proposal was mentioned in an HST Daily Report posted Friday by SpaceRef.com:
The newspaper articles say this object has been named "Sedna" and is thought to be slightly smaller than Pluto. That would put it between Pluto and three Edgeworth-Kuiper Belt objects roughly half Pluto's diameter. See David Jewitt's 1000 km Scale KBOs.
Note: When A/CC first posted these news links at 1742 UTC, this object was described as being a member of the "inner Oort Cloud," which would be a first-ever discovery. However, it is not yet clear that this is a proper description. The "inner" (non-spherical) Oort Cloud region has been defined as being made up of objects with orbits that average between 2,000 and 15,000 times the distance beween Earth and Sun. See Tumbling Stone for an Oort Cloud diagram.
Postscripts: Three other Australian news sites picked up The Australian story around 2130 UTC on March 14th, and BBC has posted a report with a 0112 UTC time stamp on the 15th [changed]. Also see the Tenagra Observatories home page with this today:
The MPEC (list of observations announcing the discovery) shows that the Tenagra II 32" (0.81-m) telescope at station 926 (Tenagra in S. Arizona) is the second set of measurements of the object that will forever change our idea of the solar system.
|Small objects – part 1/2||Major News for 14 March 2004|
Follow-up during 8-14 March
The archive work was by the Hungarian team of Krisztian Sarneczky and Brigitta Sipocz at the Szeged University (SZTE) Asteroid program. He is a geography teacher and physics doctoral student, and she is a first-year physics student. They do guest NEO observing together and when clouded out they have been generating a flood of additional positions found in the NEAT SkyMorph archive for objects of all sizes. This past week that included five small objects listed below.
If an asteroid's orbit brings it to within 0.05 AU of Earth's orbit, it is categorized as "potentialy hazardous" unless it has an absolute magnitude H greater than 22.0, which corresponds to a diameter on the order of 135
Notes: Diameters in the following observation summary table are rough best estimates from a standard but very inexact H-to-size formula using H (absolute magnitude) from the JPL NEO Orbital Elements page, source also for Earth MOID (minimum orbital intersection). Other planetary MOIDs are from Lowell Observatory. Current Minor Planet Center H is also given, along with the original H from each object's discovery MPEC. Priorities and visibilities are from the European Spaceguard Central Node (SCN).
|News briefs – part 1/1||Major News for 14 March 2004|
Risk monitoring:  If you don't follow A/CC Major News regularly, you may be looking at today's news and wondering, Where is the impact risk monitoring report? There are no objects with impact solutions under current observation. The most recent had its last impact solutions removed on March 6th.