98 articles
Henry Rishbeth
Henry Rishbeth was a British ionospheric physicist, trained at Cambridge under J. A. Ratcliffe, whose definitive studies of the F2 layer earned the Royal Astronomical Society's Gold Medal in 2001.
Ian Axford
Ian Axford (1933–2010) was a New Zealand space physicist who led the Max Planck Institute for Aeronomy and shaped theories of the magnetosphere and cosmic rays.
J. A. Ratcliffe
J. A. Ratcliffe, known as John Ashworth Ratcliffe, was a British radio physicist at Cambridge who helped prove radio waves reflect from the ionosphere and trained wartime radar scientists.
J. Randall Jokipii
J. Randall Jokipii, born Jack Randolph Jokipii (1939–2022), was an American space physicist at the University of Arizona known for his theory of cosmic-ray transport in the heliosphere.
Jack R. Jokipii
Jack R. (Randy) Jokipii (1939–2022) was an American space plasma and cosmic-ray physicist, Regents Professor at the University of Arizona, known for quasi-linear theory and the 22-year cosmic-ray cycle.
Jacques Blamont
Jacques-Émile Blamont (1926–2020) was a French astrophysicist who founded France's first space laboratory, the Service d'aéronomie, and became the first scientific and technical director of CNES.
James A. Van Allen
James A. Van Allen (1914–2006) was an American space scientist at the University of Iowa who discovered Earth's radiation belts via Explorer 1 in 1958.
James C. G. Walker
James C. G. Walker (1939–2022) was a South African-born scientist, professor at the University of Michigan, best known for research on the origin and evolution of Earth's atmosphere.
James Dungey
James Wynne Dungey (1923–2015) was a British space scientist who proposed in 1961 that Earth's magnetosphere is open, via magnetic reconnection, the foundation of modern magnetospheric physics.
Jenifer Haselgrove
Jenifer Haselgrove, born Jenifer Wheildon Brown in 1930, is a British physicist whose Haselgrove equations became a standard tool for computing how radio waves travel through the ionosphere.
Johannes Geiss
Johannes Geiss (1926–2020) was a German-Swiss experimental physicist at the University of Bern, best known for leading the Apollo Solar Wind Composition experiment on the Moon.
John Alexander Simpson
John Alexander Simpson (1916–2000) was an American physicist at the University of Chicago who built the particle detectors that made the first cosmic-ray measurements at Mars, Jupiter, and Saturn.
John Campbell Brown
John Campbell Brown (1947–2019) was a British solar physicist who held Glasgow's Regius Professorship of Astronomy and served as the 10th Astronomer Royal for Scotland.
John Evershed
John Evershed (1864–1956) was an English astronomer who discovered the Evershed effect, the radial outflow of gases from sunspot centers, in 1909 while directing the Kodaikanal Observatory in India.
John Paul Wild
John Paul Wild (1923–2008) was an Australian radio physicist who classified the Sun's radio bursts, built the Culgoora radioheliograph, developed the Interscan landing system, and chaired CSIRO from 1978 to 1985.
John R. Winckler
John R. (Jack) Winckler was an American experimental physicist at the University of Minnesota who discovered auroral X rays and made the first confirmed visual documentation of sprites.
Jørgen Christensen-Dalsgaard
Jørgen Christensen-Dalsgaard, born 1950 in Kolding, Denmark, is a Danish astrophysicist at Aarhus University known for pioneering helioseismology, the study of the Sun's interior through its oscillations.
Joseph Kaplan
Joseph Kaplan (1902–1991) was an American physicist at UCLA who studied the light of the upper atmosphere, helped create aeronomy, and chaired the US committee for the International Geophysical Year.
Joseph Wyan Chamberlain
Joseph Wyan Chamberlain (1928–2004) was an American astronomer and geophysicist specializing in the aurora, airglow, and planetary atmospheres; an airglow band system bears his name.
Judith Lean
Judith Lean is an American solar physicist at the Naval Research Laboratory whose models of solar irradiance variability quantify the Sun's role in climate change.
Juri Toomre
Juri Toomre is an astrophysicist at the University of Colorado Boulder and a JILA fellow since 1974, known for research on the Sun's interior through convection, dynamos, and helioseismology.
Justin C. Kasper
Justin C. Kasper is an experimental space plasma physicist who led the SWEAP instrument on NASA's Parker Solar Probe and won a 2010 PECASE award.
Kazunari Shibata
Kazunari Shibata (柴田 一成) is a Japanese solar astrophysicist at Kyoto University known for his unified model of solar flares and the discovery of superflares.
Kinsey Anderson
Kinsey Anderson (1926–2012) was an American space physicist and UC Berkeley professor who built balloon, rocket, and satellite instruments to study Earth's aurora, solar flares, and the solar wind.
Knut Ångström
Knut Ångström (1857–1910) was a Swedish physicist at Uppsala University who built the standard instruments for measuring solar radiation, and whose 1900 carbon dioxide experiment set back greenhouse climate theory for decades.
Kristian Birkeland
Kristian Birkeland (1867–1917) was a Norwegian physicist whose 1896 solar-particle theory of the aurora founded space plasma physics, and who co-invented the Birkeland–Eyde nitrogen fixation process behind Norsk Hydro's fertilizer industry.
Lennard Fisk
Lennard Fisk is an American space physicist at the University of Michigan, known for his 1974 theory of anomalous cosmic rays and his service as a NASA associate administrator.
Leo Goldberg
Leo Goldberg (1913–1987) was an American astronomer known for pioneering studies of the sun from space, including the first recognition of coronal holes in solar wind data.
Leonard Culhane
Leonard Culhane, known as Len Culhane, is a solar and X-ray astronomer who led UK spectrometers from the Ariel satellites to Hinode, winning the 2006 RAS Gold Medal.
Lorenzo Sironi
Lorenzo Sironi is an astrophysicist at Columbia University who studies the plasma physics of black holes and neutron stars through simulations, and received the 2025 PECASE award.