Planck team receives Gruber cosmology prize
May 15, 2018
Last week the Gruber foundation announced that this year’s cosmology prize is awarded to the Planck team, which includes scientists at the Max Planck Institute for Astrophysics (MPA). From 2009 to 2013 the European Space Agency’s Planck observatory collected data that has provided cosmology with the definitive description of the universe on the largest and smallest scales. “These measurements,” the Gruber Prize citation reads, “have led to the determination of cosmological parameters (matter content, geometry, and evolution of the universe) to unprecedented precision.”
The Planck team and the Principal Investigators of the two instruments, Nazzareno Mandolesi and Jean-Loup Puget, will divide the $500,000 award, with the Planck team receiving $250,000 and Mandolesi and Puget $125,000 each. The Prize will be awarded on August 20, at the General Assembly of the International Astronomical Union, in Vienna, Austria.
The Planck observatory consisted of two instruments, each tuned to its own portion of the electromagnetic spectrum and both invisible to the human eye. The High Frequency Instrument, under the direction of Puget, studied the universe in the far-infrared regime; the Low Frequency Instrument, under the direction of Mandolesi, observed at longer wavelengths in the microwave regime. Two MPA directors, Simon White and Rashid Sunyaev, were co-Investigators on these instruments and secured long-term support from the German Aerospace Center for a team at MPA. Led since 2003 by Torsten Enßlin, this team contributed essential software infrastructure to the project, the mission simulation package, a work-flow engine, and a data management system.
Using Planck, astronomers were able to observe the earliest cosmic light with unprecedented precision. This Cosmic Microwave Background (CMB) is the relic radiation from Big Bang and it allows us to see the moment that the universe had cooled enough for neutral hydrogen to form and for photons and matter to decouple and go their separate ways. That “flashbulb” moment, just 380,000 years after the Big Bang itself, provides a sort of snapshot—a “baby picture” of the universe long before any stars or galaxies had formed.
Planck provided a new census of today’s universe: 26.8 percent dark matter, 68.3 percent dark energy, and 4.9 percent ordinary matter. The observatory also found extremely robust evidence that the geometry of the universe is “flat”—that parallel lines truly never meet—a key prediction of so-called “inflationary” theories for the very early evolution of the universe and for the origin of all structure within it. Planck not only vastly improved the study of the fluctuations in the CMB that, billions of year later, would grow into the structures we see around us today. Planck was also able to trace those fluctuations back in time more precisely, verifying a 35 year-old prediction of inflationary theories which propose that all cosmic structure originated as quantum fluctuations of the vacuum itself a tiny fraction of a second after the initial Big Bang.
MPA scientists participated in a variety of aspects of the scientific preparation and exploitation of the mission. In particular, they were involved in cosmological studies and studies of the Sunyaev-Zeldovich effect, a distortion of the spectrum of the CMB caused by hot gas in galaxy clusters lying between us and the last scattering surface. The theory behind this effect was first described by Rashid Sunyaev, almost 50 years ago, long before he became a director at MPA, but it took almost 30 years to obtain the first convincing observational detections and Planck has provided detailed measurements for far more clusters than ever before.