Astronauts orbiting Earth not too long ago photographed not one however two comets whereas an aurora present danced beneath them.
The Worldwide House Station (ISS) Expedition 73 crew took a number of photos of comets Lemmon (C/2025 A6) and SWAN (C/2025 R2) in latest weeks that had been simply posted to NASA‘s web site and social media pages after the top of the lengthy authorities shutdown.
Comets are small our bodies fabricated from ice and mud; once they method our solar, radiation strain and warmth give them spectacular tails. Auroras are mild exhibits that occur when charged particles from the solar work together with Earth’s environment and magnetic area, whereas airglow is luminescence attributable to chemical reactions excessive within the environment.
NASA did not say who on the crew took the images, however they give the impression of being similar to photos taken by Japan Aerospace Exploration Company (JAXA) astronaut Kimiya Yui. Yui, in contrast to the NASA crew, was capable of hold posting on social media channel X in the course of the shutdown. (The NASA astronauts had been allowed to carry out solely important duties in the course of the shutdown, resembling ISS science and upkeep.)
Yui supplied descriptions of his images as effectively. “You may … distinguish between the 2 kinds of tails: ion and mud,” Yui wrote (in Japanese; translation by xAI’s Grok device) on Oct. 20 of a Lemmon picture with the comet backdropped by a starry, bluish-purple sky. (NASA posted a comparable picture from that very same day on its web site.)
Extra photos got here shortly. “After a busy day involves an finish, I have been persevering with to take images to assuage my fatigue. These days, my supply of therapeutic has been Lemmon-chan, I suppose?” Yui posted on X with a collection of photos on Oct. 22. “I discover myself considering issues like, ‘What sort of expression will you present me right now, I ponder?’ and heading towards the window, and that second feels as fulfilling as heading out on a date.”
Yui despatched out one other picture collection on Oct. 21, noting modifications in Lemmon’s brightness and tail — in addition to modifications in Earth’s environment. Each the Oct. 21 and Oct. 22 photograph units on Yui’s feed are much like an Oct. 23 picture on NASA’s web site.
Then, on Oct. 24, Yui discovered Lemmon showing to soften right into a spectacular aurora of inexperienced and yellow mild, which seems to be like an entry on NASA’s picture web site. Lemmon was 57.2 million miles (92.1 million kilometers) from Earth and the ISS was above Fargo, North Dakota when the picture was taken.
“It was identical to a mermaid swimming by means of a sea of auroras,” Yui mentioned of Lemmon. He added the present was “too magnificent” to make use of the acquainted “chan” honorific when referring to Lemmon, so he selected to undertake the extra formal “Lemmon-san.”
That very same day, Yui pivoted his consideration to what NASA identifies as Comet SWAN, which was about 27.2 million miles (43.8 million km) from Earth on the time. “Because the comet approaches the solar, the alternatives to {photograph} it from the ISS have turn into very quick,” Yui famous of the picture, which exhibits SWAN floating above inexperienced and yellow bands of airglow off the coast of Newfoundland and Labrador, Canada.
It is uncommon to have two brilliant comets seen within the sky at roughly the identical time, and particularly uncommon for them to peak in brightness so shut to one another: Lemmon and SWAN each had been at their brightest round Oct. 20 and Oct. 21.
Lemmon was found in January by College of Arizona astronomer David Carson Fuls in photos from the Mount Lemmon Survey, utilizing the college’s eponymous telescope close to Tucson. SWAN was present in September by Ukrainian newbie astronomer Vladimir Bezugly utilizing photos from the Photo voltaic Wind Anisotropies (SWAN) instrument on the European House Company‘s space-based Photo voltaic and Heliospheric Observatory (SOHO).
