The Egg Nebula (also known as RAFGL 2688 and CRL 2688) is a bipolar protoplanetary nebula approximately 3,000 light-years away from Earth. Its peculiar properties were first described in 1975 using data from the 11 μm survey obtained with sounding rocket by Air Force Geophysical Laboratory (AFGL) in 1971 to 1974.

1997年5月12日 · The Egg Nebula, also known as CRL 2688, is shown on the left as it appears in visible light with the Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2) and on the right as it appears in infrared light with Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS).

CRL 2688是一个距离我们约1kpc，动力学年龄约为250年的原行星状星云。 其所处的特殊演化阶段，使其成为研究晚型星及其星周包层演化的理想实验室。

2022年4月6日 · We present observations of the carbon-rich protoplanetary nebula CRL 2688 made with the Institut de Radioastronomie Millimétrique 30 m telescope in the 3 and 2 mm bands. In total, 196 transition lines belonging to 38 molecular species and isotopologues are detected, among which, to the best of our knowledge, 153 transition lines and 13 species ...

2022年4月6日 · We present observations of the carbon-rich protoplanetary nebula (PPN) CRL 2688 made with the Institut de Radioastronomie Millimetrique (IRAM) 30 m telescope in the 3mm and 2mm bands.

1997年12月30日 · We have discovered, within the dark lane that bifurcates the bipolar lobes of CRL 2688, a compact source of unpolarized light. Our imaging polarimetry shows that this source is not the post-asymptotic giant branch star that illuminates the nebula; we conclude that the compact source is a companion star.

2011年10月25日 · We constructed a two-dimensional dust scattering model of stellar radiation through CRL2688 that successfully reproduces the details of the nebular geometry, its integrated spectral energy distribution, and nearly all of its color variations.

During the Air Force Cambridge Research Laboratory (AFCRL) Rocket Surveys, Price and Walker discovered a strong infrared emission from object CRL 2688 (AF 803-2935) in 1974. Martin Cohen identified this infrared source with an oval nebula on the photo plates of the «Palomar Observatory Sky Survey» (POSS).

2012年1月17日 · CRL 2688 shows a faint spherical nebulosity out to angular radii r ∼ 40'' from the star. We call this region the nebular "envelope" within which thin spherical shells mimic the conspicuous co-centric rings or arcs of varying size and brightness.

We constructed a two-dimensional dust scattering model of stellar radiation through CRL 2688 that successfully reproduces the details of the nebular geometry, its integrated spectral energy distribution, and nearly all of its color variations.