Instruments flying past the comet will record optical information on the impact. In 2012, the European Space Agency hopes to have the Rosetta spacecraft orbit comet Wirtanen, take measurements, and place instruments on the comet. If successful, it will provide the critical information needed to test many theories described in this chapter. The greatest advance in understanding will come from testing conflicting predictions of better theories. This will require landing on and drilling into a comet.
New evidence spawns new theories, and the testing cycle begins again.
However, when only one explanation is taught and seldom questioned, the cycle stops. In science, we should never think we have a final or proven answer. This site best viewed with Netscape 6 or Internet Explorer 5.5 or greater.