Ghost of Jupiter

NGC 3242, Caldwell 59 · Planetary nebula in Hydra

Magnitude
7.7
Size
0.42′ × 0.35′
Effective surface brightness
20.5 mag/arcsec²
Best months
Feb, Mar, Apr
Declination
-19°
Filter
Dual-band recommended

A bright, blue-green planetary the apparent size of Jupiter. Very bright per pixel; keep subs short.

Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.

How long with each smart telescope

Total integration for a solid image of the Ghost of Jupiter, default sub length, recommended filter, and how much of each frame it fills. Click a cell for the full Bortle 1 to 9 table.
TelescopeIn frameBortle 3 (rural)Bortle 5 (suburban)Bortle 7 (urban edge)
ZWO Seestar S5010 s subs, dual-band11 px9 min52 subs9 min56 subs12 min74 subs
ZWO Seestar S50 Pro10 s subs, dual-band11 px9 min57 subs10 min62 subs14 min82 subs
ZWO Seestar S3010 s subs, dual-band6 px9 min57 subs10 min62 subs13 min80 subs
ZWO Seestar S30 Pro10 s subs, dual-band7 px10 min61 subs11 min66 subs14 min87 subs
DwarfLab DWARF 315 s subs, dual-band9 px11 min46 subs13 min51 subs17 min69 subs
DwarfLab DWARF mini15 s subs, dual-band6 px8 min34 subs9 min37 subs12 min49 subs
DwarfLab Draco30 s subs, dual-band17 px15 min30 subs15 min30 subs15 min30 subs
DwarfLab DWARF II15 s subs8 px24 min98 subs31 min124 subs59 min235 subs
Vaonis Vespera II10 s subs11 px7 min40 subs9 min54 subs19 min114 subs
Vaonis Vespera Pro10 s subs15 px15 min92 subs20 min120 subs41 min247 subs
Vaonis Vespera 310 s subs10 px6 min38 subs9 min52 subs18 min109 subs
Vaonis Vespera Pro 210 s subs15 px14 min87 subs19 min115 subs39 min236 subs
Unistellar eQuinox 24 s subs19 px7 min102 subs8 min124 subs14 min217 subs
Unistellar Odyssey4 s subs27 px33 min496 subs38 min574 subs1 h 01 min915 subs
Celestron Origin10 s subs17 px5 min30 subs5 min30 subs5 min32 subs
Celestron Origin Mark II10 s subs20 px5 min30 subs5 min30 subs7 min44 subs

Open in the calculator

Imaging the planetary nebula

Planetary nebulae are small but intensely bright per pixel in OIII and H-alpha, so they respond very well to a dual-band filter and do not need much time for the main shell. The faint outer halos most of them have are a different proposition and need hours. Keep subs short if the central region saturates.

Per-telescope pages