Hubble's Variable Nebula is a curious reflection nebula enveloping the bright star R Monocerotis. The variability of R Monocerotis was discovered at Athen's Observatory in 1861, but it wasn't until 1916 that Edwin Hubble discovered that the nebula itself varies even over time scales as short as a few weeks.Carl Lampland at Lowell Observatory made an intensive study of this object over a period of 30 years and recorded 900 images. He found that the nebula changed by as much as 1" arc displacement in just 4 days. These changes are presumed to be caused by shadows cast on the nebulosity by dark material orbiting the star R Monocerotis.
These images taken three months apart show a slight change in the appearance of the nebula. They are both a series of 4x20 sec exposures with the 50 cm Newtonian. A false colour palette has been applied to the inset images to accentuate the detail. I hope to get a whole series during the course of this winter and construct an animated gif showing variations on time scales of a few weeks.
1999 January 9th
Images below are again 4x20 sec exposures. The image on the right has been processed with a Lucy-Richardson algorithm, which has accentuated a dark rift which has now appeared on the west side of the nebula. Both images have been resampled in PSP vs. 5 to enlarge the image scale.
1999 March 9th
A bright region has now just appeared north of R Monocerotis. This feature was first noted by Tom Polakis imaging from Arizona. It is the bright spot just above the star that is illuminating the nebula. Take a look here at his fine animation over a period of two months. This is an 8x20 sec exposure with 50cm f/4 and SX CCD.
Worth Hill Observatory Index
