Discover the cosmos!
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2025 September 30
Explanation:
Comet Lemmon is brightening and moving into morning northern skies.
Besides
Comet SWAN25B and
Comet ATLAS,
Comet C/2025 A6 (Lemmon) is now the third comet
currently visible with binoculars and on long camera exposures.
Comet Lemmon was discovered early this year
and is still headed into the inner
Solar System.
The comet will round the Sun on November 8, but first it will pass its nearest to the Earth — at about half the
Earth-Sun distance
— on October 21.
Although the brightnesses of comets are
notoriously hard to predict, optimistic estimates have
Comet Lemmon
then becoming visible to the unaided eye.
The comet should be best seen in predawn skies until mid-October,
when it also becomes visible in evening skies.
The
featured image showing the comet’s split and rapidly changing ion
tail
was taken in
Texas,
USA late last week.