彗星LONEOS (C/2007 F1) 已经进入地球轨道以内,亮度大增,最新拍摄的照片上,绿色的彗星拖着一条暗弱的短尾,从地面的观测来看,彗星比预报明亮1等以上,9月29日实际亮度大约在8.2等,而当时的预报约10等,彗星继续向太阳靠近,并于10月27日经过近日点,日心距离在0.4AU,估计亮度可达4等左右,近日点前北半球的观测者可在傍晚西方低空搜索这颗彗星,近日点之后,彗星迅速向南移动,但与太阳的角距很小,地面观测条件很差。
C/2007 F1 (LONEOS)
C/2007 F1 (LONEOS)
Epoch 2007 Oct. 27.0 TT = JDT 2454400.5
T 2007 Oct. 28.7595 TT MPC
q 0.402372 (2000.0) P Q
z -0.000216 Peri. 153.7117 +0.9137883 +0.3906744
+/-0.000018 Node 172.8882 -0.0827780 -0.0889004
e 1.000087 Incl. 116.0843 +0.3976667 -0.9162261
Date TT R. A. (2000) Decl. Delta r Elong. Phase m1 m2
2007 09 27 11 55.28 +27 58.8 1.595 0.877 29.6 34.4 10.4
2007 10 02 12 11.74 +27 36.5 1.440 0.782 31.2 41.6 9.7
2007 10 07 12 32.23 +26 46.7 1.277 0.686 32.3 51.0 8.9
2007 10 12 12 58.53 +24 59.7 1.109 0.594 32.2 63.6 8.0
2007 10 17 13 32.90 +21 13.2 0.944 0.509 30.3 80.6 6.9
2007 10 22 14 16.80 +13 34.6 0.801 0.442 25.7 102.5 6.0
2007 10 27 15 06.90 +00 23.5 0.721 0.405 20.4 121.4 5.4
2007 11 01 15 53.05 -15 42.3 0.739 0.412 21.8 116.3 5.5
2007 11 06 16 27.14 -29 00.4 0.842 0.459 27.5 94.7 6.2
2007 11 11 16 49.82 -37 56.7 0.983 0.533 31.3 75.0 7.2
2007 11 16 17 05.21 -43 49.1 1.133 0.620 33.1 60.6 8.2
2007 11 21 17 16.54 -47 52.8 1.276 0.714 33.8 50.4 9.1
2007 11 26 17 25.69 -50 52.6 1.410 0.810 34.0 43.0 9.8
2007 12 01 17 33.69 -53 13.6 1.534 0.905 34.1 37.6 10.5
http://www.spaceweather.com/
COMET LONEOS: "Comet LONEOS (C/2007 F1) is here!" reports Tony Cook of Leeds, UK, who took this picture on Sept. 30th:
"Over the next month this comet is predicted to increase in brightness to 4th magnitude--barely visible to the naked eye but an easy target for backyard telescopes," he says. Comet LONEOS is not a frequent visitor to the inner solar system. One analysis suggests it was last in the neighborhood 42,000 years ago. It's equally possible, however, that the comet has never been close to the sun before; this could be its first plunge. The uncertainty adds suspense to Oct. 29th when LONEOS will approach the sun almost as close as Mercury. Will fresh veins of ice newly heated by sunlight burst forth to produce surprisingly bright jets and clouds? Stay tuned! Cook's Sept. 30th image "was taken under bright moonlight just before dawn," he adds. "Even under these difficult conditions a fine but faint linear tail can be seen. As the moon departs and the comet gets closer to the sun, the view can only get better and brighter!" Astrophotographers, if you wish to try to catch the comet, look below the handle of the Big Dipper for a green 8th magnitude fuzzball. |