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The Deep Impact mission was designed so that much of the mission-critical science would be done from Earth-based telescopes. These facilities would observe the comet before, during, and after impact [...], On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

In March 2001, the Hayabusa spacecraft target, Asteroid 25143 Itokawa, made its final close approach to Earth prior to the spacecraft's launch. We carried out an extensive observing campaign from January to September 2001 to better characterize this near-Earth asteroid. Global physical properties of the surface of Itokawa were characterized by analyzing its photometric properties and behavior. Results included here capitalize on analysis of broadband photometric observations taken with a number of telescopes, instruments, and observers. We employed a Hapke model to estimate the surface roughness, single particle scattering albedo, single particle scattering characteristics, phase integral, and geometric and bond albedo. We find that this asteroid has a higher geometric albedo than average main belt S-class asteroids; this is consistent with results from other observers. The broadband colors of Itokawa further support evidence that this is an atypical S-class asteroid. Broadband colors show spectral characteristics more typically found on large-diameter main-belt asteroids believed to be space-weathered, suggesting the surface of this small diameter, near-Earth asteroid could likewise be space-weathered. Keywords: Surfaces, asteroids; Asteroids; Photometry; Regoliths; Asteroids, composition

1996 [JA.sub.1], which approached to 0.003 AU of the Earth on 1996 May 19.7 UT, was discovered on films exposed 5 days earlier during the course of the high-ecliptic-latitude Bigelow Sky Survey. The utility of high-latitude surveying for near-Earth objects is demonstrated by the fact that 1996 [JA.sub.1] traveled through the usual ecliptic survey region at a rate of 5 [degrees] [hr.sup.-1], and would likely have escaped detection even at V = 11. Rapid astrometry and communication through the Minor Planet Center and the World Wide Web facilitated follow-up observations that indicate 1996 [JA.sub.1] has a mean diameter of 170 m, a rotational period of 5.23 hr, and an albedo of 0.30. With a spectrum consistent with the V class, it is possible that 1996 [JA.sub.1] shares the same source as the HED meteorites.

The Hubble Space Telescope (HST) first observed the periodic comet SL9 on 1 July 1993 (1). After the successful HST servicing mission in December 1993, the HST began observing SL9 [...], The Hubble Space Telescope made systematic observations of the split comet P/Shoemaker-Levy 9 (SL9) (P designates a periodic comet) starting in July 1993 and continuing through mid-July 1994 when the fragments plunged into Jupiter's atmosphere. Deconvolutions of Wide Field Planetary Camera images indicate that the diameters of some fragments may have been as large as ~2 to 4 kilometers, assuming a geometric albedo of 4 percent, but significantly smaller values (that is,

Spacewatch technology have determined the presence of about 40 Earth-approaching asteroids with dimensions less than 1.3 AU including 13 with measurements less than 50 m. Objects whose orbits dominate the Spacewatch observations also dominate the simulated distribution. Results indicated that asteroids with low eccentricity levels, a diversity of inclinations and abnormal spectral properties form an asteroid belt located near the Earth.

Although the standardized uptake value (SUV) is currently used in fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) imaging, concerns have been raised over its accuracy and clinical relevance. Dependence of the SUV on body weight has been observed in adults and this should be of concern in the pediatric population, since there are significant body changes during childhood. The aim of the present study was to compare SUV measurements based on body weight, body surface area and lean body mass in the pediatric population and to determine a more reliable parameter across all ages. Sixty-eight pediatric FDG-PET studies were evaluated. Age ranged from 2 to 17 years and weight from 11 to 77 kg. Regions of interest were drawn at the liver for physiologic comparison and at FDG-avid malignant lesions. SUV based on body weight (SUV[subbw] ) varied across different weights, a phenomenon less evident when body surface area (SUV[subbsa] ) normalization is applied. Lean body mass-based SUV (SUV[sublbm] ) also showed a positive correlation with weight, which again was less evident when normalized to bsa (SUV[subbsa-lbm;). The measured liver SUV[subbw] was 1.1±0.3, a much lower value than in our adult population (1.9±0.3). The liver SUV[subbsa] was 7.3±1.3. The tumor sites had an SUV[subbw] of 4.0±2.7 and an SUV[subbsa] of 25.9±15.4 (65% of the patients had neuroblastoma). The bsa-based SUVs were more constant across the pediatric ages and were less dependent on body weight than the SUV[subbw] . These results indicate that SUV calculated on the basis of body surface area is a more uniform parameter than SUV based on body weight in pediatric patients and is probably the most appropriate approach for the follow-up of these patients. [ABSTRACT FROM AUTHOR]