UPDATE: Early eye-witness reports indicate that comet A3 is not yet a naked-eye object. It’s best seen by taking images, which you can learn more about doing here.
What time will comet A3 be visible tomorrow? If you’ve been watching the incoming (and perfectly safe) space rock, also known as Comet Tsuchinshan-ATLAS (C/2023 A3), this week you’ll have seen the crescent moon glide past it, becoming slimmer and more delicate each night. You may not have realized it, but you were watching the moon gradually approach the sun, which it will eclipse on Oct. 2.
Yes, the new moon on Oct. 2 will obscure the center of the sun’s disk in a spectacular annular solar eclipse. For more on that, see below. For now, let’s consider exactly when and where you need to look to see comet A3 with your naked eyes on Wednesday, Oct. 2.
Comet A3 reached its perihelion — the closest it gets to the sun — on Sept. 27 and will get closest to Earth on Oct. 12, when it will pass about 44 million miles (71 million km) from Earth.
It’s currently visible in in the east before sunrise, its bright tail arching away from the sun, but you do need to be up very early and have a clear view of the eastern horizon.
Where To See Comet A3: Wednesday, Oct. 2:
Position: east-southeast, 19.5 degrees from the sun in Leo
Time: an hour before sunrise where you are (around 07:00 in the U.S.)
Expected magnitude: +4.5
Comet’s distance from the sun: 61.6 million km
Comet’s distance from Earth: 106.2 million km
This morning, comet A3 will be visible a close to the east-southeast an hour before sunrise, now with no moon in sight since it’s inching towards the sun to becomes a new moon.
The comet should be visible just above east-southeast about 75 minutes before sunrise and will be best seen in astronomical darkness, which will last until about 60 minutes before sunrise.
Oct.2’s ‘Ring Of Fire’ Solar Eclipse
On Oct. 2 a “ring of fire” will be visible for over six minutes as a spectacular annular solar eclipse occurs — but only for those in the southern hemisphere.
Visible only from a narrow path through the Pacific Ocean to the Atlantic Ocean, via Easter Island, southern Chile and southern Argentina, a smaller-than-average moon will cross the sun’s disk to cover only its center, causing a ring of light around the new moon. The entire event can only be viewed safely through solar eclipse safety glasses.
Expect stunning images from among the moai monoliths of Easter Island and from the fjords and mountains of Patagonia.
The following solar eclipse will occur on March 29, 2025, when the extreme northeastern U.S. states will get a view of a sun rising in the east while partially eclipsed. It will occur precisely one lunar year after the total solar eclipse on April 8, 2024.
Check my feed every day this week and next for a daily “comet tracker” with sky-charts and tips for viewing Comet A3.
Wishing you clear skies and wide eyes.
