NGC 4361: A planetary nebula to crow about

NGC 4361 is an attractive planetary nebula in Corvus, the Crow. Image: Adam Block.

Amidst the myriad spring galaxies lies NGC 4361, a large and bright planetary nebula located in the southern constellation of Corvus, the Crow. Locating it means dipping low towards the murkier skies close to the horizon, but it’s well worth the extra effort to find and observe it.

Corvus lies south of the ‘bowl’ of Virgo asterism.NGC 4361 forms the apex of an upside-down triangle with magnitude +2.9 Algorab (delta [d] Corvi) and magnitude +2.6 Gienah (gamma [g] Corvi), the northern pair of stars in Corvus’ irregular quadrilateral-shaped asterism of third-magnitude stars. It lies about 2.5° from both stars. NGC 4361 culminates at around 11.30pm BST at an elevation of just short of 20°. 


NGC 4361 lies within in Corvus’ main quadrilateral-shaped asterism, with the Antennae galaxies located 3.5° south-west of Gienah (gamma Corvi), the star at the north-west of the quadrilateral. AN graphic by Greg Smye-Rumsby.

NGC 4361 appears clearly as a nebula through a 150mm (six-inch) telescope at a power of 50x, though a small telescope will struggle to show it as anything other than an ‘out-of-focus star’ at low power. Image show a delightful object, covering almost 2’ at its fullest.

As interesting as NGC 4361 is it’s not Corvus’ stand out object. This accolade falls on the remarkable Antennae galaxies, the colliding NGC 4038 and NGC 4038. The pair lie just over 5° west of NGC 4361, so it’ll be a waste if you miss out on trying to find and observe them. 

NGC 4038 and NGC 4039 are popularly called the Antennae for the streamers of stars, gas and dust stripped out from both galaxies as a result of their violent celestial encounter. They are located just to the west of the Corvus’ aforementioned asterism; sweep 3.5° south-west of Gienah (gamma [γ] Corvi, magnitude +2.6). Both are rather small and similarly-bright galaxies (magnitude +10.7, with NGC 4039 to the south slightly the larger, spanning 3.2’ x 2.2’ as opposed to 2.6’ x 1.8’ for NGC 4038. Owing to the Antennae’s low altitude from the UK, a 150mm (six-inch) telescope shows the pair as just a fuzzy halo about 2.5’ across.

Deep amateur images can show some of the turmoil and destruction that the encounter has unleashed, including the amazing ‘antennae’.

The amazing Antennae galaxies NGC 4038 (top) and NGC 4039. Image: Basudeb Chakrabarti.