Table 3. Identifications and properties of the bluer cloud of post-AGB stars, mixed with the AGB stars, selected in the high-quality color-color diagram S65/S90 vs. S65/S160, presented in the right panel of Fig. 1.
Name | Other common name(s) | Relevant information |
|---|---|---|
IC 2149 | bipolar (in the process of forming?) (Vázquez et al., 2002) | |
NGC 2818 | in front of an open cluster C 0914-364, bipolar age 600–1000 yrs ? | |
Frosty Leonis Nebula | protoplanetary nebula, bipolar | |
NGC 3242 | Ghost of Jupiter | t ~ 2800 yrs (Steffen et al., 2008) |
NGC 6210 | t ~ 2000 yrs (Pottasch et al., 2009) | |
NGC 6826 | Blinking Nebula | almost circular, early evolutionary status t ~ 5000 yrs (Guerrero et al., 1998) |
NGC 7009 | Saturn Nebula | t ~ 7000 yrs (but not much evolved) (Sabbadin et al., 2004) |
Abell 78 | PN G081.2-14.9 | hydrogen-defficient “born-again PNe” after a He flash (Borkowski et al., 1993) |
NGC 7662 | Blue Snowball Nebula Caldwell 22 | triple shell; ellipsoidal t ~ 1050 yrs (Guerrero et al., 2004) |