SPIE Astronomical Telescopes and Instrumentation 2016

Insights into dark energy and gravity waves as well as progress on building the Large Millimeter Telescope, Large Synoptic Survey Telescope, Thirty Meter Telescope, James Webb Space Telescope (JWST), and other major projects to probe the skies were in focus at SPIE Astronomical Telescopes + Instrumentation in Edinburgh earlier this year.

Plenary speakers and many of the 2400 other attendees also brought their latest insights and research into software and instrument design for CubeSats and ground- and space-based telescopes that explore our universe.

Plenary speaker Hitoshi Murayama, director of the Kavli Institute for the Physics and Mathematics of the Universe at University of Tokyo and a professor at University of California, Berkeley, used the somewhat terrifying prospect of a future “big rip” tearing apart the cosmos to introduce the topic of dark energy and how it might be measured.

The theory goes that if there is sufficient dark energy, the universe will at some point pull itself apart completely. The only problem, as Murayama noted candidly, is “we have no clue what dark energy is.”

What may help change that is a new piece of spectroscopy equipment being built for the 8.2m-diameter Subaru Telescope in Hawaii. Called the “Prime Focus Spectrograph,” it combines the giant 900 megapixel Hyper Suprime-Cam CCD detector with an array of 2400 optical fibers for spectroscopy and the very large field of view (1.5°) of Subaru.

That would allow a census of individual galaxies and their redshifts as seen from Earth, which in turn would give astrophysicists more information about the distribution of dark matter and energy.

The wide field of view from Subaru means this telescope could complete that census of redshifted stellar emission lines over the course of a 300-night survey, whereas similarly large instruments would take more than five years.

A plenary talk by Richard Ellis from the European Southern Observatory (ESO) also focused on how spectroscopy and adaptive optics are expected to aid the quest to understand how the universe transformed from a largely dark place to its most active period of star formation.

Ellis said the NIRSpec kit on board the JWST will look for signs of “reionization” of hydrogen just a few hundred million years after the Big Bang.

“The challenge is to witness and physically understand the birth of the first galaxies,” Ellis said, pointing out that while Hubble Space Telescope images have shown that star-forming galaxies were likely present in the first billion years of the universe, exactly when and how they were born remains a mystery.

“During this period, early stars and galaxies formed, and the universe became bathed in ultraviolet light for the first time,” Ellis said. “Sometime during this era, hydrogen in the intergalactic medium also transitioned from a neutral gas to one that was fully ionized.”

Ellis said he hopes JWST’s spectrograph and the emerging suite of ground telescopes now under construction can reveal what was going on during that first billion-year period. Recent data from the European Space Agency’s Planck satellite suggest that the reionization began after around 400 million years, which is later than had previously been thought.

Other plenary speakers included Martin Hendry, professor of gravitational astrophysics and cosmology at University of Glasgow (UK), and Monica Grady of the Open University (UK), who was a science advisor on a team that successfully orbited and landed a robotic probe on the surface of a comet in 2014.

Hendry’s team was involved with construction and installation of the twin Laser Interferometer Gravitational-Wave Observatories (LIGO) in the United States, and he detailed work that preceded LIGO’s discovery of gravitational waves last year.

Further gains in gravity-wave astronomy are expected to come from Advanced LIGO, detectors in Italy and Germany, ones being built in India and Japan, and even the LISA Pathfinder mission, Hendry said.

Grady described the dramatic story of the European Space Agency’s comet-chaser Rosetta mission, the first space mission to touch down on a comet. The probe, the Philae lander, arrived on comet 67P Churyumov-Gerasimenko in 2014 and produced data for 70 hours before its batteries died.

Improving and supporting gender equity in the astrophysics community were topics of discussion at several events during SPIE Astronomical Telescopes + Instrumentation 2016.

A lively discussion followed an SPIE Women in Optics talk by Dame Jocelyn Bell Burnell, whose discovery of pulsars led to her PhD supervisor being awarded the 1974 Nobel Prize in Physics.

Participants at a gender equity session chaired by Claire Max, director of the University of California Observatories, also raised awareness among conference organizers about policies excluding children from scientific conferences and exhibitions.

As a result, SPIE modified its rules to allow children to accompany their parents into conference activities in Edinburgh. SPIE is reassessing the policy for future SPIE meetings.

Extensive highlights from speakers, the 12 conferences, two-day exhibition, poster sessions, and other activities, plus recordings of the presentations from seven plenary talks are available on SPIE.org and optics.org.

SPIE Astronomical Telescopes + Instrumentation 2018 will be held 10-15 June in Austin, Texas (USA).

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