天文學獎
2020

2020年度邵逸夫天文學獎頒予羅傑・布蘭福德 (Roger D Blandford) 以表彰他對理論天體物理學的根本性貢獻，特別是在活躍星系核的基本理解、相對論性噴流的形成和準直、黑洞的能量提取機制和激波中的粒子加速及其相關的輻射機制。羅傑・布蘭福德是美國史丹福大學文理學院盧克・布魯森講座教授、物理學教授暨粒子物理學及天文物理學教授。

羅傑・布蘭福德是當代最出色的全方位理論天體物理學家之一。他關注極為廣泛的天體物理學問題，作出了重大貢獻，堪稱為一位罕有的「全才」科學家。他是引力透鏡效應模擬和詮析方面的先驅。他對來自費米太空船的γ射線數據的分析，和引力波的研究，均有建樹。他在研究領域最重要的貢獻，是對活躍星系核及其相對論性噴流的基本理解。

In 1918, the American astronomer Heber Curtis used the Crossley Reflector at Lick Observatory in California to take optical photographs of nearby galaxies. When observing M87, the central elliptical galaxy in the Virgo galaxy cluster 53 million light years from the Sun, Curtis noted the lack of a spiral structure and observed a “curious straight ray … apparently connected with the nucleus by a thin line of matter”. This measurement heralded the discovery of radio jets, the ejection of highly collimated, relativistic plasma streams or “blobs”, from a central energy source. Forty years later radio astronomers in the UK and Australia discovered a new class of “radio stars” not obviously connected with bright optical nebulae. Caltech astronomer Maarten Schmidt then used the large 5 m Hale telescope on Palomar to identify a faint, compact optical nebula associated with one of these radio stars, 3C273. Schmidt interpreted the substantial (16%) redshift of all spectral lines in the optical spectrum as being caused by the expansion of the Universe. If so, 3C273 must be 2.4 billion light years from us, 45 times further away than M87, and the optical luminosity of the faint compact speck would have to be about one thousand times greater than the 100 billion stars of our Milky Way. Thus began the subject of quasars, quasi-stellar radio sources. Many quasars and other somewhat less spectacular “active galactic nuclei” (AGN) exhibit powerful radio jets.