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Introductory remarks by S. Kulkarni on the occasion of the viewing of
"Gehrels Maniac Lecture, September 29, 2015" (an event organized
by Kasliwal).
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https://www.youtube.com/watch?v=lG08SL8fDDk
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7 Feb 2017, Hameetman Auditorium, Caltech campus
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Neil Gehrels passed away yesterday. Until his untimely death Neil
was the Chief of Astro-particle Physics Laboratory at GSFC and College
Park Professor at the University of Maryland until his untimely
death yesterday. He grew up in an astronomical family. His father was
Tom Gehrels who worked with Gerard Kuiper and transformed University
of Arizona into a powerhouse of astronomy and planetary astronomy.
[I recommend the interested student to read the book "Under Desert
Skies" to get a glimpse of Neil's upbringing].
Neil attended the University of Arizona and graduated with a degree
in music and physics in 1976. He then came to Caltech and worked
with Rochus ("Robbie") Vogt . When Robbie became the Provost Neil
switched to Stone at the Space Radiation Laboratory. The title of
his PhD thesis was "Energetic oxygen and sulfur ions in the Jovian
magnetosphere". His key thesis paper was the discovery of oxygen
and sulfur Jupiter's magnetosphere, which given that Jupiter is a
gas giant and so the expected dominant elements is Hydrogen and
Heliuma, was a surprise. Gehrels & Stone attributed this anomaly
to the volcanos on Io. Following graduation he went to GSFC and
stayed there until his death. At GSFC his interests switched to
gamma-ray astronomy and hard X-ray astronomy. His early achievement
was the detection of a strong gamma-ray line (847 keV arising from
decay of Cobalt 56) from SN 1987A.
Neil had an amazing career in space astrophysics in two distinct
capacities. First, he was an incredibly productive astronomer:
53,535 citations, 749 refereed papers and an h-index of 116 (on the
day of his death).
Next, most astronomers aspiring to be leaders in space astronomy
would be happy if they got to lead or play a prominent role in one
mission in their life. One may think that his claim to fame is
being the Principal Investigator of the Swift Gamma-Ray Burst
Mission. However, he was much more than that. He was the Project
Scientist for the Compton Gamma Ray Observatory (one of the four
Great Observatories), the US Mission Scientist of the ESA-Russian
Integral, Deputy Project Scientist for the Fermi Gamma-ray Space
Telescope and Project Scientist for the WFIRST mission. The latter
came about because of his early involvement in proposing the SANP
Dark Energy mission (led by Perlmutter & Levi). Neil's work was
recognized by the Rossi Prize of the AAS and the Draper medal of
the National Academy of Scinces (amongst other awards). Neil was a
core member of the LIGO Science Team.
Clearly, Neil was an exceptional leader. He lead but in a harmonious
fashion. He was everyone's friend and yet at the same time saw
missions go from concept to very productive facilities. I saw this
in action when Swift Gamma-ray Burst mission was proposed. I was
on the opposing team. Swift won. Immediately, Neil called me up
and asked me to join the Swift Science Team. I event went to Cape
Canaveral to see the launch (but came back empty handed; the flight
was canceled four times owing to hurricanes). The move to invite
me to the science team was certainly strategic: after all I was a
very active player in GRB astronomy especially in radio and almost
unique access to optical followup (in that era). However, his
gesture also led to a lifelong friendship. Neil managed to inspire
loyalty and I cannot recall ever saying no to any request that Neil
made. This combination of being a genuine friend whilst making
strategic moves is rare. In fact I know no other such person in my
life.
I would like to end by summarizing three notable papers.
A. Gehrels et al. (2004) The Swift Gamma-ray burst mission (1930
citations). The large number of citations is no surprise. Swift had
remarkable success across many branches of astronomy: SNe, GRBs,
TDEs, flare stars, AGN, magnetars, etc.
B. Atwood et al. (2009). Fermi GLAST (1702). Fermi had a big impact
in the field of quasars, Galactic gamma-ray sources, gamma-ray
bursts and unexpectedly in the field of millisecond pulsars.
C. Gehrels (1986). Confidence limits for Poisson statistics (1325).
Neil was most proud of this paper.
We all will miss Neill. However, I take comfort that Neil led a
vigorous life of research and discovery. Neil built missions that
made it possible for many astronomers such as myself to make stunning
discoveries about our Universe and at the same time was a most
effective leader who accomplished big missions with a gentle style.
[Note added after the event: About ten days prior to this event
the President of the Tel Aviv University called me and informed me
that the Dan David Foundation was recognizing Gehrels, Udalski and
me for our contributions to the development of Time Domain Astronomy
(TDA). The Foundation has three themes: past, present and future.
TDA is seen (and correctly so) as the future area of inquiry in
Astronomy. The recognition not only comes with cash (always welcome)
but also festivities (colloquia, talks) in Israeli Universities
during the third week of May. I was looking forward to meeting
Neil in May when on Monday I learnt of Neil's untimely death.]