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We have used data obtained with the Fine Guidance Sensors on the Hubble SpaceTelescope to derive precise astrometric parallaxes for four classical novae:V603 Aql, DQ Her, GK Per, and RR Pic. All four objects exceeded the Eddingtonlimit at visual maximum. Re-examination of the original light curve data forV603 Aql and GK Per has led us to conclude that their visual maxima wereslightly brighter than commonly assumed. With known distances, we examine thevarious maximum magnitude--rate of decline (MMRD) relationships that have beenestablished for classical novae. We find that these four objects show a similarlevel of scatter about these relationships as seen in larger samples of novaewhose distances were determined using indirect techniques. We also examine thenebular expansion parallax method, and find that it fails for three of the fourobjects. In each case it was possible to find an explanation for the failure ofthat technique to give precise distance estimates. DQ Her appears to sufferfrom an anomalously high extinction when compared to field stars on its sightline. We suggest that this is likely due to local material, which may also bethe source of the IRAS detections of this object.

HST Fine Guidance Sensor Parallaxes for Four Classical Novae