Physical world and mathematics

Ian Heilbron

Sir Ian Morris Heilbron (1886–1959) was a Scottish organic chemist, a world authority on squalene who helped introduce DDT, contributed to penicillin chemistry, and won the Davy and Royal Medals.

Ian Joughin

Ian Joughin is a glaciologist at the University of Washington's Applied Physics Laboratory known for measuring and modeling the flow of the Greenland and Antarctic Ice Sheets.

Sep 20, 2026

Ian Manners (1961–2023) was a British-Canadian chemist who pioneered organometallic polymers and crystallization-driven self-assembly, holding a Canada 150 Research Chair at the University of Victoria.

Ian McDougall (geochronologist)

Ian McDougall (1935–2018) was an Australian geochronologist at the Australian National University known for argon dating, the geomagnetic reversal time-scale, and dating Turkana Basin hominin sites.

Ian Morison

Ian Morison (1943–2024) was a British radio astronomer at the University of Manchester's Jodrell Bank Observatory who helped develop the MERLIN array and served as the 35th Gresham Professor of Astronomy from 2007 to 2011.

Ian Robinson (physicist)

Ian K. Robinson is a condensed-matter physicist who established surface X-ray diffraction as a standard technique and pioneered Bragg coherent diffraction imaging, holding chairs at University College London and Brookhaven National Laboratory.

Ian Stewart (mathematician)

Ian Stewart, born in Folkestone in 1945, is a British mathematician who spent his career at the University of Warwick studying dynamical systems and symmetry, and has written more than 120 books.

Ian W. D. Dalziel

Ian W. D. Dalziel is a British-born field geologist and tectonicist known for mapping the Southern Andes and West Antarctica and for work on the supercontinent Rodinia.

Ian W. Hamley

Ian W. Hamley, born 1965, is a soft-matter physical chemist and Diamond Professor of Physical Chemistry at the University of Reading, known for research on block copolymer and peptide self-assembly.

Sep 20, 2026

Ian Walmsley

Ian A. Walmsley is a British quantum optics scientist known for the SPIDER pulse-measurement technique and the first demonstration of Boson Sampling, and Provost of Imperial College London from 2018 to 2025.

Iapetus (moon)

Iapetus is the third-largest moon of Saturn, a cratered icy body with one hemisphere dark and one bright and an equatorial ridge up to 20 km high.

IAU designated constellations

The IAU designated constellations are the 88 sky regions into which the International Astronomical Union divided the entire celestial sphere, fixed in 1922 and bounded by published coordinate lines.

Ib Madsen

Ib Madsen, born 1942 in Copenhagen, is a Danish algebraic topologist who spent 37 years at the University of Aarhus, proved Mumford's conjecture, and shared the 2011 Ostrowski Prize.

Ibandronate

Ibandronate, also called ibandronic acid, is a nitrogen-containing bisphosphonate drug sold in the United States as Boniva since 2003 for treating and preventing postmenopausal osteoporosis.

Oct 21, 2026

Ibcasertib

Ibcasertib (chiauranib, CS2164) is an oral multi-kinase inhibitor from Chipscreen Biosciences targeting Aurora B, VEGFRs, PDGFRs, c-KIT, and CSF-1R; phase I MTD 50 mg/day, phase III in ovarian cancer and small cell lung cancer.

IBM Quantum

IBM Quantum is IBM's full-stack quantum computing program, offering cloud access to superconducting quantum processors since 2016, the open-source Qiskit software, and a roadmap toward fault-tolerant systems.

IBM Research

IBM Research is IBM's research and development division, a global network of laboratories founded in 1945 as the Watson Scientific Computing Laboratory at Columbia University.

Oct 22, 2026

IBM RXN for Chemistry

IBM RXN for Chemistry is a free, web-based platform from IBM Research, launched in 2018, that uses artificial intelligence to predict chemical reaction products and plan retrosynthetic routes.

IBMX

IBMX, also called 3-isobutyl-1-methylxanthine, is a synthetic xanthine derivative that potently inhibits phosphodiesterases, raising cAMP and cGMP; it is widely used in cell culture and signaling research.

Ibn al-Haytham (الحسن بن الهيثم)

Ibn al-Haytham, also known as Alhazen or Alhacen, was a mathematician, physicist, and astronomer born in Basra around 965 who spent most of his career in Cairo.

Ibotenic acid

Ibotenic acid is a neurotoxic amino acid found in Amanita muscaria and related mushrooms, first isolated in Japan in the 1960s and used in neuroscience research.

IBTrACS

IBTrACS, the International Best Track Archive for Climate Stewardship, is a NOAA dataset that unifies global tropical cyclone best-track records from multiple meteorological agencies, spanning the 1840s to the present.

IC 10

IC 10 is a small irregular dwarf galaxy in the constellation Cassiopeia and a member of the Local Group, the closest-known starburst galaxy, discovered by Lewis Swift in 1887.

IC 1101

IC 1101 is a supergiant elliptical galaxy at the center of the Abell 2029 cluster and the largest known galaxy, about 1.7 million light-years wide.

IC 1127

IC 1127, also cataloged as Arp 220, is a pair of merging spiral galaxies in the constellation Serpens, about 250 million light-years away, and the nearest ultra-luminous infrared galaxy.

IC 1396

IC 1396, also known as Sharpless 2-131, is a large emission nebula and open star cluster in Cepheus, ionized by the multiple star HD 206267 and home to the Elephant's Trunk Nebula.

IC 1613

IC 1613, or Caldwell 51, is a dwarf irregular galaxy in Cetus about 2.3 million light-years away whose low dust makes it a key distance calibrator.

IC 1805

IC 1805, also known as Melotte 15, is a young open star cluster in Cassiopeia, embedded in the Heart Nebula, containing 8 or 9 O-type stars.

IC 2149

IC 2149 is a planetary nebula in the constellation Auriga, a shell of gas thrown off by an aging star, about magnitude 10.6 and roughly 8 arcseconds wide.