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Blobrana · L

RE: Asteroid 2009 HD21

Blobrana · L

2009 HD21
Earth Impact Risk Summary

Torino Scale (maximum)	0
Palermo Scale (maximum)	-2.80
Palermo Scale (cumulative)	-2.50
Impact Probability (cumulative)	4.3e-07
Number of Potential Impacts	193

V_impact	19.79 km/s
V_infinity	16.35 km/s
H	18.2
Diameter	0.779 km
Mass	6.5e+11 kg
Energy	3.1e+04 MT
all above are mean values weighted by impact probability

Analysis based on
25 observations spanning 1.6658 days
(2009-Apr-20.32627 to 2009-Apr-21.99209)

Source

Blobrana · L

2009 HD21
Earth Impact Risk Summary

Torino Scale (maximum)	0
Palermo Scale (maximum)	-3.20
Palermo Scale (cumulative)	-2.59
Impact Probability (cumulative)	4.9e-07
Number of Potential Impacts	390

V_impact	18.62 km/s
V_infinity	14.91 km/s
H	18.2
Diameter	0.771 km
Mass	6.3e+11 kg
Energy	2.6e+04 MT
all above are mean values weighted by impact probability

Analysis based on
22 observations spanning 1.0082 days
(2009-Apr-20.32627 to 2009-Apr-21.33448)

Source

Blobrana · L

Orbital elements:
2009 HD21                                           PHA, Earth MOID = 0.0017 AU
Epoch 2009 June 18.0 TT = JDT 2455000.5                 MPC
M 327.94391              (2000.0)            P               Q
n   0.37032342     Peri.  139.62936     +0.76028944     +0.64958398
a   1.9205042      Node   179.85327     -0.64650135     +0.75679830
e   0.5185068      Incl.   17.90763     -0.06321371     +0.07278035
P   2.66           H   18.2           G   0.15           U   9

MPEC 2009 - H29