2012年3月冥王星及卫星掩星事件摘要
1.冥王星掩星：
2.冥卫一 卡戎掩星
3.冥卫二 尼克斯掩星：
4.冥卫三许德拉
Notes:
C/A: geocentric closest approach, in arcsec
P/A: Planet position angle wrt to star at C/A, in deg
vel: velocity in plane of sky, in km/sec, positive= prograde, negative= retrograde
R: instrumental magnitude in UCAC2 system
J, H, K: 2MASS magnitudes (50.0 = not in 2MASS)
R*, J*, H*, K* are normalized magnitudes to a common
shadown velocity of 20 km/sec by the relationship:
Mag* = Mag_actual + 2.5*log10[velocity/20 (km/sec)]
Delta: Planet range to Earth, AU
long: East longitude of sub-planet point, deg, positive towards East
loc. t.= UT + long: local solar time at sub-planet point, hh:mm
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Selection criteria:
Maximum geocentrique closest approach considered: 0.33500000000000002 arcsec
Day light exclusion (range loc. t.): 12.0hs to 12.0 hs (t1 = t2 -> no exclusions)
List below has: 2 entries
Reference ephemeris: DE418/JPL_14
Offset applied to ephemeris off_ra(mas) = A * (t-t0) + B
Offset applied to ephemeris off_de(mas) = C * (t-t0) + D
t0 = 2005.0000000000000 yrs
A = 0.0000000000000000 (mas/yr)
B = -84.000000000000000 (mas)
C = 0.0000000000000000 (mas/yr)
D = -53.000000000000000 (mas)
pm = proper motion applied? (ok, no)
ct = uc (UCAC2); 2m (2MASS); fs (field star)
f = multiplicity flag
0 - no multiple entries per star in astrometry
1 - single position from 2 or more uc/2m entries
2 - single position from 1 uc/2m entry only
3 - fs position from entry with more N contributions
4 - fs position from entry with best (x,y) error
5 - fs position from entry with brightest R mag.
6 - fs position from average over all entries
(see details in Assafin et al. 2009)
E_ra, E_de: error of star position (mas); (9999 = no estimation)
pmra, pmde: star proper motion (mas); (9999 = no proper motion)
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,当Kp指数达到6或以上时，我国境内有可能观察到极光；当前极光活动水平
，极光为9时漠河可能见极光，
级，当地磁暴级别达到G2或以上时，我国境内有可能见极光
置顶卡
变色卡
千斤顶
显身卡
楼主