Fleming 1 is an unusual planetary nebula situated in the Centaurus constellation.
Yet it is not clear after who it was named
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Annes Astronomy News says:
Fleming 1 is a planetary nebula that lies about 10,000 light-years away in the constellation of Centaurus, while moving away from us at approximately 28.6 kilometers per second. It is named after the Scottish astronomer Williamina Fleming, who discovered the nebula in 1910.
(May 15, 1857 – May 21, 1911) was a Scottish astronomer active in the United States. During her career, she helped develop a common designation system for stars and cataloged thousands of stars and other astronomical phenomena. Among several career achievements that advanced astronomy, Fleming is noted for her discovery of the Horsehead Nebula in 1888
That article's Notable discoveries section says
During her career, Fleming discovered a total of 59 gaseous nebulae, over 310 variable stars, and 10 novae.
Most notably, in 1888, Fleming discovered the Horsehead Nebula on a telescope-photogrammetry plate made by astronomer W. H. Pickering, brother of E.C. Pickering. She described the bright nebula (later known as IC 434) as having "a semicircular indentation 5 minutes in diameter 30 minutes south of Zeta Orionis". Subsequent professional publications neglected to give credit to Fleming for the discovery. The first Dreyer Index Catalogue omitted Fleming's name from the list of contributors having then discovered sky objects at Harvard, attributing the entire work merely to "Pickering". However, by the time the second Dreyer Index Catalogue was published in 1908, Fleming and her female colleagues at the HCO were sufficiently well-known and received proper credit for their discoveries.
Fleming is also credited with the discovery of the first white dwarf:
The first person who knew of the existence of white dwarfs was Mrs. Fleming; the next two, an hour or two later, Professor E. C. Pickering and I. With characteristic generosity, Pickering had volunteered to have the spectra of the stars which I had observed for parallax looked up on the Harvard plates. All those of faint absolute magnitude turned out to be of class G or later. Moved with curiosity I asked him about the companion of 40 Eridani. Characteristically, again, he telephoned to Mrs. Fleming who reported within an hour or so, that it was of Class A.
— Henry Norris Russell13
Fleming published her discovery of white dwarf stars in 1910. Her other notable publications include A Photographic Study of Variable Stars (1907), a list of 222 variable stars she had discovered; and Spectra and Photographic Magnitudes of Stars in Standard Regions (1911).
She died of pneumonia in Boston on May 21, 1911
The quote by is from Notes on White Dwarfs and Small Companions Astronomical Journal, Vol. 51, p. 13 (1944)
Though effusing complements to Pickering, it seems that the first line "The first person who knew of the existence of white dwarfs was Mrs. Fleming" is meant to ensure some bit of historical record was set straight.
From this answer to Has great eyesight been necessary for astronomers?:
The title of a book on this subject The Glass Universe is likely a play on words, the photographic plates were made of glass, and so was the ceiling. (Space.com review, The Atlantic, Magiscenter, BBC interview in YouTube, NPR)