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.

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.

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

A newly discovered comet is about to make its closest pass to Earth on Tuesday night. It should be visible over the Bay Area before it disappears — and won’t be seen again for more than a thousand years.

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.

Astronomer Gianluca Masi captured spectacular footage of a glowing meteor trail wrapping around the colossal tail of Comet Lemmon on Oct. 24, as the wandering solar system body approached the constellation Serpens Caput in Earth's sky.

A pair of once-in-a-lifetime comets are 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),