Roger Angel

Last updated
Roger Angel

FRS
Born
James Roger Prior Angel

(1941-02-07) February 7, 1941 (age 83) [1]
Nationality American, British
Education Oxford (B.A., Ph.D.)
California Institute of Technology (M.S.)
Known for Spin casting
Lobster-eye optics
Space sunshade
Scientific career
Fields Astrophysics, Optics
Institutions Columbia University
University of Arizona

James Roger Prior Angel (born February 7, 1941) is a British-American astrophysicist known for telescope design and the development of spin casting, a technique used to produce mirrors for several of the largest optical telescopes in the world. [1] [2] He is a Regents' Professor of Astronomy and Optical Sciences at the University of Arizona. [3]

Contents

Education

He graduated from St Peter's College, Oxford, with a BA, in 1963, from California Institute of Technology, with an MA in 1966, and from the University of Oxford, with a D Phil, in 1967. [1]

Career and research

He has taught at Columbia University. He is a Fellow of the Royal Society. He was elected a Fellow of the American Academy of Arts and Sciences in 1990. [4]

In 1979, he proposed the lobster-eye optics principle for X-rays. [5]

In 2006, Angel proposed assembling a space sunshade to mitigate global warming by placing trillions of 0.6-meter, 1-gram disks of refractive material into stable orbit between the Earth and the Sun (Lagrange point 1, or L1). The disks would be launched in stacks of 800,000 by electromagnetic acceleration and transported to L1 (1.5 Gm from Earth) via ion propulsion. After separation the individual disks would remain in place by autonomously modulating solar radiation pressure. Together the cloud of disks would deflect 2% of solar radiation onto the Earth, enough to counteract the warming effect of a 100% increase in atmospheric carbon dioxide from pre-industrial levels. He concluded that such a sunshield "could be developed and deployed in ≈25 years at a cost of a few trillion dollars, <0.5% of world gross domestic product (GDP) over that time." [6]

On August 23, 2012, Angel and his inventions were the subject of a story on NPR's Morning Edition . [7]

Awards

Related Research Articles

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Lobster-eye optics are a biomimetic design, based on the structure of the eyes of a lobster with an ultra wide field of view, used in X-ray optics. This configuration allows X-ray light to enter from multiple angles, capturing more X-rays from a larger area than other X-ray telescopes. The idea was originally proposed for use in X-ray astronomy by Roger Angel in 1979, with a similar idea presented earlier by W. K. H. Schmidt in 1975. It was first used by NASA on a sub-orbital sounding rocket experiment in 2012. The Lobster Eye Imager for Astronomy, a Chinese technology demonstrator satellite, was launched in 2022. The Chinese Einstein Probe, launched in 2024, is the first major space telescope to use lobster-eye optics. Several other such space telescopes are currently under development or consideration.

References

  1. 1 2 3 "Roger Angel | American astronomer | Britannica".
  2. Gibbs, Wayt (December 1, 2005). "Breaking the Mold". Scientific American.
  3. "J. Roger Angel". The University of Arizona. Retrieved April 2, 2024.
  4. "Book of Members, 1780-2010: Chapter A" (PDF). American Academy of Arts and Sciences . Retrieved April 18, 2011.
  5. Hartline, Beverly Karplus (4 January 1980). "Lobster-Eye X-ray Telescope Envisioned". Science. 207 (4426): 47–47. doi:10.1126/science.207.4426.47. ISSN   0036-8075 . Retrieved 29 December 2023.
  6. Angel, Roger (2006-11-14). "Feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1)". Proceedings of the National Academy of Sciences. 103 (46): 17184–17189. doi:10.1073/pnas.0608163103. ISSN   0027-8424. PMC   1859907 . PMID   17085589.
  7. Palca, Joe (2012-08-23). "Telescope Innovator Shines His Genius On New Fields". NPR .
  8. "Fellowships Reward Bright Stars", Associated Press, The Free Lance-Star, Terri Likens, June 19, 1996
  9. "J. Roger P. Angel - Lightweight Mirrors for Astronomical Telescopes". National Inventors Hall of Fame . Retrieved June 4, 2016.