Rosseland-forelesningen 2016 i opptak
21. april holdt Bart De Pontieu årets Rosseland-forelesning "Living with our nearest star". Se foredraget i opptak.
Sammendrag av forelesningen:
The Sun is our nearest star. It provides a unique laboratory to study, from relatively close by, physical processes that occur throughout the wide expanse of the universe.
We also live in the Sun's atmosphere. The Sun's radiation is critical to life on Earth, while solar storms and resulting space weather can put at risk satellites, power grids and other critical infrastructure. A better understanding of what drives the violent dynamics and relentless heating of the Sun's atmosphere is thus not only of interest to solar physicists, but also to astrophysicists, and to our increasingly high-tech civilization.
Fortunately the Sun has never been scrutinized as closely as now: technological advances have enabled a flotilla of satellites and telescopes to study the Sun at unprecedented spatial, temporal and spectral resolution, while advances in computing, driven by Moore's law, now allow realistic numerical modeling of the complex physical processes that dominate the Sun's atmosphere.
I will discuss some recent exciting discoveries that highlight the synergy between numerical modeling and observations with NASA's Interface Region Imaging Spectrograph (IRIS) and Solar Dynamics Observatory (SDO), and JAXA/NASA's Hinode spacecraft as well as ground-based telescopes. These discoveries provide insight into what heats the solar atmosphere to millions of degrees, what drives violent solar eruptions, and how the Sun provides us with glimpses of what occurs in distant astrophysical objects such as accretion disks.
Bart De Pontieu is a principal physicist at Lockheed Martin’s Solar & Astrophysics Laboratory which is part of Lockheed Martin Advanced Technology Center in Palo Alto, California. De Pontieu is the science lead for NASA’s solar satellite Interface Region Imaging Spectrograph (IRIS) which was built by Lockheed Martin and which has been observing the Sun’s atmosphere since its launch in 2013. He is also adjunct professor at the Institute of Theoretical Astrophysics at the University of Oslo. His research focuses on using high-resolution observations and numerical models to understand the physical processes that cause the rapid rise of temperatures from 10,000 degrees to millions of degrees in the low solar atmosphere. Throughout De Pontieu’s involvement with half a dozen NASA missions, he has prioritized public outreach through lectures, class-room visits and websites.