C/2021 S3 PANSTARRS

Closest to Sun on 2024 Feb 14 at 1.32AU
Closest to Earth on 2024 Mar 15 at 1.30AU
Maximum magnitude 8 in Feb-March 2024
Orbital period N/A parabolic

C/2021 S3 PANSTARRS + NGC 5367 on 2023 December 16.

This dynamically new (first visit) comet was discovered on 2021 September 24th by the PANSTARRS 2 telescope located at Haleakala, Maui Hawaii.
The orbital viewing circumstances are not very favourable, but southerners are favoured in the leadup to perihelion,
with the comet maintaining visibility in predawn skies.

During December 2023, the comet can be found trekking eastwards in Centaurus, in the hour before dawn, brightening from magnitude 11.0 to 10.0.
The best period of visibility will be between December 11 to December 25, before moonlight begins to interfere.
On December 8, the comet is 3 degrees North of Centaurus A galaxy NGC 5128
On December 20, the comet is adjacent to magnitude 13 galaxy IC 4367

During January 2024, the comet continues its north-easterly trek through the constellations of Centaurus, Lupus and Scorpius,
best observed in the hour before dawn, brightening from magnitude 10.0 to 9.0
On January 6, the comet is 18’ South of magnitude 13 galaxy NGC 5843 in Lupus.
On January 15, it enters dark nebula Barnard 228
Moonlight interferes from January 23rd
On January 30, the comet lies 1 degree southeast of Antares in Scorpius and would make a great photo opportunity with wide field imaging equipment.

During February 2024, the comet continues its north-easterly trek through the constellations of Scorpius, Ophiuchus and Serpens,
best observed in the hour before dawn, brightening from magnitude 9.0 to 8.0
On February 1, the comet is 2 degrees East of Antares and would make a great photo opportunity with wide field imaging equipment
however moonlight interferes until the morning of February 8.
On February 13-14, it is within 30’ of magnitude 7.7 globular cluster Messier 9.
On February 15, it is adjacent to magnitude 8.3 globular cluster NGC 6356.
Moonlight interferes from the morning of February 23.

During March 2024, the comet continues its north-easterly trek through the constellations of Serpens, Aquila and Sagitta.
It remains in the morning sky best observed in the hour before dawn, steadily fading from magnitude 8.0 to 8.5
On March 1, the comet has reached maximum brightness of magnitude 8, sporting a nice dust tail.
On March 5, it is 30’ North of Eta Serpentis
On March 13, it lies a degree east of 4th magnitude open cluster IC 4756.
On March 18, it lies a degree east of 6th magnitude open cluster NGC 6709.
On March 20-21, it traverses the 8th magnitude open cluster NGC 6738.
On March 23, it lies a degree East of Zeta Aquilae
Moonlight interferes from March 24.
On the nights of March 30-31, the comet traverses the “Coat Hanger” asterism Collinder 399. Astrophotographers take note.

During April 2024, the comet becomes increasingly more difficult to observe from the southern hemisphere and now favours northern observers.
It continues its northerly trek through the constellations of Vulpecula and Cygnus.
It remains in the morning sky, best observed in the hour before dawn, steadily fading from magnitude 8.5 to 9.5.
On April 8, it lies 20’ East of emission nebula NGC 6813 in Vulpecula.
On April 18, it lies within a degree East of Eta Cygnii.
Moonlight interferes from April 22.
On April 24, it lies about 30’ West of the Crescent Nebula NGC 6888 in Cygnus.
On April 30, the comet traverses the Gamma Cygni Nebula IC 1318A.

During May 2024, the comet now favours northern observers. It continues its northerly trek through the constellation of Cygnus.
It remains in the morning sky, best observed in the hour before dawn, steadily fading from magnitude 9.5 to 10.5.
On May 13, it situates between stars Omega 1 and 2 Cygnii.
Moonlight interferes from May 22.

During June 2024, the comet is visible to northern observers, continuing its northerly trek through the constellations of Cygnus and Cephus.
It remains in the morning sky, best observed in the hour before dawn, steadily fading from magnitude 10.5 to 11.0.
On June 14, it lies 30’ West of magnitude 9.7 galaxy NGC 6946.
 

Observations


C/2021 S3 PANSTARRS ON 2023 November 03 at 17:45UT.
Using a C11 RASA f/2.2 + Canon 6D. 5 mins. FOV 1 deg. from Little Desert National Park, Victoria, Aus.
approximate mag 11.0. tail 15' in PA 248