Machholz Comet Babies Lead the Way (July 16, 2012)
Hi-res TIF (1.4M)
As it is making its fourth appearance in the SOHO/LASCO cameras, we didn't think that Comet 96P/Machholz could hold many more surprises for us. Shows how wrong you can be about comets! On July 14, 2012, just as Comet Machholz entered the LASCO C2 cameras, two of SOHO's ever-diligent comet hunters spotted a pair of much smaller, fainter comets a few hours ahead of Machholz. At first they thought that these were unrelated, but upon closer inspection, it became obvious that these two tiny objects were in fact fragments of Comet Machholz, forging out ahead of their parent body.
Fragmentation events like this are not that uncommon, particularly for Comet Machholz (see http://sungrazer.nrl.navy.mil/index.php?p=news/family_ties), but it is the first time this particular comet has been directly seen doing this! It is unknown exactly when this fragmentation happened, but given that the comets are some 1.4-million kilometers ahead of their parent, it was most likely around one orbit ago at their previous passage by the Sun. For them to be separated like this, they must have split apart at different speeds -- probably on the order of 25m/s (~45mph) according to approximate calculations. Assuming these fragments survive, they should precede Comet Machholz by half a day or more on its next return in late 2017.
More details of this exciting event can be found at the Sungrazer here: http://sungrazer.nrl.navy.mil/index.php?p=news/machholz_babies
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