A MARTÍNEZ, HOST:
The Andromeda Galaxy is one of the most photographed star systems in the universe, so astronomer Robert Fesen was puzzled when colleagues told him about a new photo that seemed to show a massive gas cloud floating nearby.
ROBERT FESEN: And they returned a few weeks later saying, no, it's real. I still didn't believe it.
STEVE INSKEEP, HOST:
To double check, Mr. Fesen enlisted help from an amateur astrophotographer.
FESEN: He came back a few days later saying, it's actually real. It's extremely faint, but it's definitely real.
INSKEEP: That photographer, Bray Falls, says some of the world's biggest telescopes failed to catch this new feature because their lenses were trained on smaller objects.
BRAY FALLS: The reason the professionals didn't notice this is basically because it's too big. All the professional observatories have much greater focal length, so they're looking at very narrow fields of view to get lots of resolution. And so they straight up just missed it.
MARTÍNEZ: The new gas cloud, or nebula, has been named Strottner-Drechsler-Sainty Object 1 or, for short, SDSO-1.
INSKEEP: This is amazing. They didn't see the forest for the trees or didn't see the gas cloud for the something else. I don't know. Anyway, researchers want to know where SDSO-1 came from. And Fesen, who teaches at Dartmouth, is helping to find answers.
FESEN: It's a remarkably large nebulosity to be undetected for all this time up till now.
MARTÍNEZ: Fesen and other scientists will keep on looking, and Falls will keep on taking pictures.
FALLS: There is kind of, like, a golden age coming up in terms of planetary nebula discovery and all kinds of nebula discovery that's possible by amateurs. And this is - it's kind of like the start timer in, like, a race to find things, is what this signifies for me. Transcript provided by NPR, Copyright NPR.