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Don Backer, astrophysicist and discoverer of millisecond pulsars, dies at 66

backer1.jpg Don Backer, an astrophysicist at the University of California, Berkeley who discovered the first millisecond pulsar, died on 25 July. He was director of Berkeley’s Radio Astronomy Laboratory and the Allen Telescope Array (ATA) in Hat Creek, California – a collection of 42 dishes that recently began scanning the sky and searching for extraterrestrial intelligence.

“Don was a terrific scientist, innovative, clear in his thinking, and renowned as a mentor by many around the world,” says Berkeley radio astronomer Geoff Bower, who will take over as interim director of the ATA. “His death leaves a huge hole personally and professionally in the department.”

Backer was born in Plainfield, New Jersey in 1943 and received his astronomy Ph.D. from Cornell University in Ithaca, New York in 1971. He was a post-doctoral researcher at the National Radio Astronomy Observatory in Charlottesville, Virginia and then a researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

He came to Berkeley in 1975 and, while there, studied black holes, pulsars, and, most recently, the emission spectrum of hydrogen from the early universe. In 1982, Backer and his colleagues discovered PSR B1937+21, the first known millisecond pulsar, an Earth city-sized star that rotates in a mere thousandth of a second. [corrected 7/28] The discovery astounded astronomers, who did not expect pulsars to rotate so fast.

Image Credit: Bob Rood


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    Jill Tarter said:

    Thanks to Bob Rood for that marvelous photo of Don – it captures his humanity, his enthusiasm, his curiosity, and the caring and thoughtful manner in which he worked with everyone of us. There really aren’t any words to say how much he is missed.

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    Barney Rickett said:

    Stunning loss to astrophysics and a personal loss to me. His discovery of the first milli-second pulsar opened a new era. Incidentally that pulsar is only 20 kilometer in diameter – way smaller than “Earth-sized”

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    Robert Magtibay said:

    I am greatly saddened by the loss of such a great mind. While employed at UCB’s Astronomy Dept., I was fortunate enough to spend a little time with him and others at the ATA sight in Hatcreek. It was a learning and exploring experience I will never forget. He took us hiking up Lassen and we even got to see the Lava tubes. It was like going exploring with one of your cool uncles…. I will always remember him as a free spirit with endless knowledge to share. I will truly miss him. My

    condolences to all his family and friends. Thank you Prof. Backer for the opportunity you had given me and for being such a “Cool Dude”. Rest in Peace…….

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    Duncan Lorimer said:

    Don was truly an amazing person. From the Galactic Center to Pulsars, the Interstellar Medium and Extragalactic Radio sources, his contributions to radio astronomy, signal processing and fundamental physics and astrophysics are widespread and substantial. As an advisor and mentor to generations of students and postdocs, Don imparted this knowledge effectively and generously. As the photo shows, his love for his work was carried by the glint in his eye and a never ending source of energy to remain at the cutting edge of astrophysics research. He will be deeply missed.

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    Adam Mann said:

    Thank you, everyone for your words. And thanks, Barney, for your comments. The post has been corrected.

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    Amanda said:

    He was both a brilliant astrophysicist and an all around extremely friendly guy.

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    Denial said:

    Millisecond pulsars? I wonder if it can be used to create an accurate clock.

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    Markjack said:

    The brightest candle pulses at 1.2 parsecs as fast.

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    Peter McCullough said:

    I second Jill Tarter’s comments and wish to send my condolences to Don’s family, friends and colleagues. Another characteristic evident in the photo is that Don is listening. One of my memories of Don from his middle to late 40’s, when I was in my 20’s and a graduate student, was that he was thoughtful and listened well.

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    Kate Ebneter said:

    Like Peter McCullough, I second Jill Tarter’s comments. My deepest condolences to his family, colleagues, and friends. Also like Peter, I was a graduate student at Berkeley in the 80s, and found Don to be one of the nicest people in the department. It’s very sad to hear of his passing at such an early age.

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