A pair of once-in-a-lifetime comets is rocketing through our skies right now, and it's a rare treat because they won't be back for hundreds of years. The comets, C/2025 A6 (Lemmon) and C/2025 R2 (SWAN),

An astronomer in Italy caught a fortuitous image of the bright comet Lemmon seemingly entwined with the glowing trail of a "shooting star."

Comet Lemmon is moving quickly west of the Big Dipper, near bright Arcturus, while Comet SWAN lies beneath the three stars that form the Summer Triangle. About 90 minutes after sunset is when to look for both.

Comet C/2025 A6 (Lemmon) will pass through the neck of the great celestial serpent represented by the constellation Serpens Caput on the nights of Oct. 26-27.

Lemmon, which is a rare green comet, can be seen with the naked eye on Oct. 21, according to the Royal Astronomical Society, with peak visibility near Halloween. SWAN may be visible using binoculars or a telescope, according to Starwalk, a real-time astronomical app for stargazing.

The interstellar object 3I/ATLAS has gathered significant scientific attention, and soon it will reach its closest point to the sun.

The comets are visible in the northwest (Lemmon) and southwest (SWAN) about 90 minutes after sunset. Lemmon is moving quickly across the sky west of the Big Dipper, close to bright star Arcturus, while SWAN is beneath the three bright stars that comprise the Summer Triangle. At magntitude +4.4, Lemmon is by far the brighter and easiest to see.

Harvard Professor Avi Loeb discusses the mystery surrounding the 31/ATLAS comet and explains his argument that it has a 40% chance of being alien technology.

They also noted that iron was not detected alongside the nickel, an uncommon pattern in comets. Rahatgaonkar and Seligman suggested that the nickel may be locked in molecules that break apart easily under sunlight, releasing the metal at low temperatures.