| Red Rectangle |
| A red nebula around the star HD 44179, detected in 1975 during a survey of infrared sources. The emission, which is intrinsic to the nebula and not scattered or reflected light, is in a broad band in the red part of the spectrum, peaking at about 640 nanometres. It is the strongest known source of this red emission, which may be a result of luminescence from hydrogenated amorphous carbon dust. |