Nov. 4th held a real treat: NASA’s EPOXI mission made a very
successful close encounter with a comet known as Hartley 2. In
fact this encounter is the closest a man-made object has ever
come to any comet – coming within 435 miles/700 km. This is only
the fifth time a spacecraft has “visited” a comet in this way.
Many may recall the “Deep Impact” mission which launched in 2005
and aimed to rendezvouz with comet Tempel 1. It did just that on
July 4th, 2005. That mission involved the spectacular release of
a washing machine-size probe, known as the “impactor,” which
collided with the comet, releasing material which was imaged by
the Deep Impact spacecraft (which is, in comparison approx the
size of a VW beetle). Scientists used the data and spectra they
observed as a means of better understanding the nature and
composition of the comet. Although the Deep Impact spacecraft
had completed its mission, NASA scientists saw potential for
continuing to use the still functioning craft and set about
determining a new sci