(137924) 2000 BD19

Infobox Planet | discovery=yes | physical_characteristics = yes | bgcolour=#FFFFC0
name=(137924) 2000 BD₁₉
discoverer=LINEAR
discovered=January 26, 2000
alt_names="none"
mp_category=Aten asteroid, Mercury-crosser asteroid, Venus-crosser asteroid, Earth-crosser asteroid, Mars-crosser asteroid
epoch=February 26, 2000 (JD 2451600.5)
semimajor=131.109 Gm (0.876 AU)
perihelion=13.749 Gm (0.092 AU)
aphelion=248.470 Gm (1.661 AU)
eccentricity=0.895
period=299.681 d (0.82 a)
inclination=25.639°
asc_node=333.878°
arg_peri=324.184°
mean_anomaly=202.259°
avg_speed=23.85 km/s
dimensions=~1.6 km
mass=?×10^? kg
density=2 ? g/cm³
surface_grav=? m/s²
escape_velocity=? km/s
rotation=? d
spectral_type=?
abs_magnitude=16.74
albedo=0.1 ?
single_temperature=~297 KAn asteroid discovered by LINEAR in January of 2000, (137924) 2000 BD₁₉ (2000 BD₁₉, also written 2000 BD19) was soon after located by DANEOPS on Palomar plates from February 10, 1997. This allowed a reasonably precise orbit determination, and as a result it was spotted again on February 27, 2001 and January 21, 2002. 2000 BD₁₉ has the closest perihelion of any known asteroid (as of July 2004), at 0.092 AU —38% of Mercury's orbital radius. That and its high eccentricity (0.895) and inclination (25.7°), seem to indicate an inactive or extinct comet. It hasn't been caught displaying cometary activity so far.

One can estimate that 2000 BD₁₉'s surface temperature reaches ~920 K at perihelion, enough to melt lead and zinc, and nearly enough to melt aluminium. 2000 BD₁₉ is considered a good candidate for measuring the effects of Albert Einstein's General theory of relativity because of how close it comes to the Sun. [Margot, Jean-Luc [http://www.astro.cornell.edu/~jlm/NEAs/2000BD19/ Measuring asteroidal perihelion advance to measure solar oblateness and test general relativity] , retrieved Dec 222007]

When it was discovered, it beat 1995 CR's record for both asteroid with the smallest perihelion and for Aten asteroid with the highest eccentricity. With a high eccentricity, not only does 2000 BD₁₉ get close to the Sun, but it also travels relatively far away from it. It has the third largest aphelion of any Aten asteroid and is one of the few Aten asteroids that is also a Mars crosser.

References

* [http://cfa-www.harvard.edu/mpec/K00/K00C49.html MPEC 2000-C49]