The Homunculus

by Albert Highe


Yeah, I have trouble pronouncing it too, but you probably recognize the Hubble image of it. http://www.space.com/images/h_eta_carinae_0105_02.jpg

The double-lobed nebula resulted when the star, Eta Carinae, erupted about 150 years ago. Eta Carinae is one of the largest and most luminous suns known, millions of times brighter than our sun. It lies within the vast Eta Carina Nebula.

While discussing observations of Eta Carina Nebula with Bob and David, Bob asked if I had looked at the homunculus. David added that he had seen both lobes. I had scanned the Eta Carina Nebula at low and high power, but hadn't looked closely at bright stars (what would be the point?). The next night, I revisited the nebula and the star, Eta, at 214X in the 13". The brighter lobe, facing toward us, was as plain as day. It was a bright ellipse, approximately 9" long, jutting out from Eta, easily visible with direct vision. It appeared to have a reddish hue. The fainter lobe, facing away, was visible with direct vision once I knew it was there. I also thought I detected structure in the lobes. At 300X, structure was unmistakable in the brighter lobe. After studying the area for several minutes, I called Bob and David over. We all made the same observations. After we returned home, I compared my notes to the Hubble image. Sure enough, our observations corresponded well. For example, in the Hubble image, the brighter lobe shows three darker regions: one spot just left and down from the central star, and another darker spot further out, and a larger dark zone along the lower edge. In the eyepiece, the two inner dark regions were visible as irregular dark patches. The zone along the lower edge showed up as a bite taken out of the smooth curve of the ellipse. The contrast of the dark patches was similar to details seen on Mars on good nights.

It was one of the more memorable objects of the trip. Be sure to take a look.


Posted on sf-bay-tac Apr 16, 2005 23:16:48 PT
Converted by report.pm 1.2 Apr 23, 2005 21:10:00 PT