April skies 2026

Sky looking North-west on Friday April 24 as seen from Adelaide at 20:20 ACST (click to embiggen). 

The First Quarter Moon is clearly visible above the horizon forming a triangle with  Jupiter and Porcyon. The Lunar X and V may be seen in a telescope or strong binoculars. The inset shows the telescopic view at this time. 

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes after sunset). 

 Comets:

 
C/2026 A1 (MAS): This is a Kreutz family comet, one of a group of related comets that pass close to the sun. Everyone was excited that it might become a super bright comet. However, it’s brightness increase stalled (everyone gasped) then started up again (everyone cheered), with what looked to be an eruption plume. 

Currently the two most likely outcomes are that the comet disintegrates before it reaches the sun (like comet ISON) or it breaks up after perihelion and forms a “headless” comet like C/2011 (W3) Lovejoy. In the latter case we may see a bright tail starching up from the horizon as twilight fades. 

There is still (given the restart in brightness) the possibility that the comet will survive, and we will see a decent comet. The comet has passed intact through the STEREO H1 imager and is in the field of view of the PUNCH (Polarimeter to Unify the Corona and Heliosphere) satellite, It has a magnitude of 6.5 and a tail extending more than 3 degrees. So fingers crossed for its survival.

There is the possibility the comet head will be around -3—4 magnitude, (about as bright as Venus), but it will fade rapidly and may be difficult to distinguish against the twilight by the time it is above the horizon in Australia. 

Western sky on the evening of Tuesday, April 7 as seen from Adelaide at 18:28 ACST ( 30 minutes after sunset, click to embiggen). If it hasn’t disintegrated,  Comet C/2026 A1 may be visible low in the twilight. 

C/2026 A1 perihelion is 4 April, the soonest we can see the comet head is probably the 6th or 7th depending on how bright it turns out to be. If there is a decent tail we should see it as the twilight fades. 

Look to the west, bright Venus will be your guide, the comet should be to the west and a bit below. As the twilight fades the comet and its tail may become more visible. As the days progress the comet gets higher, but it will also be dimming rapidly. 

We may see the tail in the late twilight, we may be in a C/2011 (W3) Lovejoy situation, where a bright, long headless tail was seen for a couple of days, or a C/2024 G3 Atlas situation, where a modest length but faint tail was visible in the late twilight for nearly a week.  Either would be good.

C/2025 R3 (PANSTARS): This is also getting a fair bit of attention. While not predicted to be as bright as C/2026 A1, it could be either a good binocular comet or a modest to good unaided eye comet, depending on multiple factors. C/2025 R3’s perihelion is 20 April and is closest to the earth on April 27. It may be visible in Australia from the 27th if the brightest predictions are correct and from the 30th if more modest predictions are correct.

Western sky on Thursday, April 30  as seen from Adelaide at 18:30 ACST (60 minutes after sunset, click to embiggen). Comet C/2025 R3 may be visible in the twilight.

C/2025 R3 is not a sungrazer, it only gets as close to the sun as between the orbits of Mercury and Venus. Magnitude predictions run anywhere between magnitude 8 (about as bright as Neptune) and 2.8 (about as bright as delta Crucis), not spectacular but easily visible after nautical twilight.