Karen Harvey Prize for Prof. Dr. Hui Tian
Professor Tian studies dynamic phenomena in the Sun’s atmosphere; his research group is a partner group of the Max Planck Institute for Solar System Research.
Prof. Dr. Hui Tian, who leads a partner group of the Max Planck Institute for Solar System Research (MPS) at Peking University in China, has received this year's Karen Harvey Prize of the Solar Physics Division of the American Astronomical Society (AAS). The AAS thus honors Tian's contributions to the understanding of small-scale and dynamic processes in the solar atmosphere. Processes of this kind may hold the key to understanding how the Sun heats its outermost envelope, the corona, to one million degrees and catapults solar wind particles into space. The award ceremony took place online. Scientists from around the world followed Tian's award lecture on the internet.
The Sun’s outer layers cannot be seen with the naked eye: trapped by strong magnetic fields, the hot plasma that flows there mainly emits extreme ultraviolet light and X-rays. Yet these layers are essential to answering some of the most exciting questions researchers still have about our star. How is it possible, that with a million degrees the Sun’s corona is more than a hundred times hotter than its visible surface? Where does the energy come from to accelerate the solar wind, the never-stalling stream of charged particles from the Sun, into space and to produce violent outbursts of radiation?
To learn more, scientists must not only look very closely at our star, but also in quick succession. The decisive processes are likely limited to small regions measuring only a few hundred kilometers and take place within a few minutes. Investigating such processes on the Sun is a challenge. Prof. Dr. Hui Tian analyses observational data from space probes such as NASA’s Solar Dynamics Observatory (SDO) and Interface Region Imaging Spectrograph (IRIS) as well as from the Japanese probe HINODE and combines these with ground-based observations from the most powerful solar telescopes on Earth, such as the Big Bear Solar Observatory in the USA.
Tian’s approach includes breaking down the ultraviolet from the Sun into its individual wavelengths. This makes it possible, among other things, to determine temperatures and speeds of the solar plasma. In this way, Tian found that intermittent high-speed plasma jets supply the corona with mass and energy. By collaborating with MPS colleagues, he also systematically investigated the properties of short-lived and small-scale bursts of ultraviolet radiation, and discovered several new types of dynamic events in sunspots. In addition, he and collaborators performed the first measurement of the global coronal magnetic field, and found persistent low-amplitude oscillations in coronal loops.
Prof. Dr. Hui Tian studied at Wuhan University in China and received his doctorate from Peking University. During his PhD study, he had a productive stay at the Max Planck Institute for Solar System Research in Germany for two years as a visiting student. After research stays at the High Altitude Observatory and the Harvard Smithsonian Center for Astrophysics in the USA, Tian accepted an appointment at Peking University in 2015. In 2016, his research group became a partner group of MPS. Recently, Tian was appointed director of the Key Laboratory of Solar Activity of the Chinese Academy of Sciences. Among his several awards are the Distinguished Young Scientist Award of the National Science Foundation of China and the Young Researcher Award of the Plasma Physics Department of the Asia-Pacific Association of Physical Societies.
Each year, the American Astronomical Society awards the Karen Harvey Prize to a young scientist who is still at the beginning of his or her scientific career and has already made important contributions to the study of the Sun.