... D rad Bacteria: Candidate Astronauts . ... Known as an extremophile, bacteria such as D. M27: Not A Comet . ... Comet C 2001 Q4 (NEAT) . ... Comet C 2002 T7 (LINEAR) . ... Discovered by the the Lincoln Near Earth Asteroid Research (LINEAR) project in October of 2002, comet C/2002 T7 is now visiting the inner solar system, making its closest approach (see animation by L. Koehn) to the Sun tomorrow, April 23rd. ... No comets of comparable brightness have graced the skies of Earth since then. ...