433 Eros

433 Eros
NASA/JPL/JHUAPL · Public domain · source
Name	433 Eros
Discovered by	C. D. Perrine
Discovery site	Lick Observatory
Discovery date	1898-08-13
Mpc name	(433) Eros
Alt names	1898 DQ
Epoch	2026-01-01
Semimajor axis	1.458 AU
Eccentricity	0.223
Period	1.76 yr
Dimensions	34.4 × 11.2 × 11.2 km
Rotation period	5.27 h
Spectral type	S-type
Albedo	0.25
Absolute magnitude	11.2

433 Eros Eros is a near-Earth asteroid discovered in 1898 by astronomer C. D. Perrine at Lick Observatory, notable for being one of the first small bodies to be targeted by a dedicated spacecraft and for intensive study that linked asteroid properties to meteorites. Its discovery influenced surveys led by institutions such as the United States Naval Observatory, Harvard College Observatory, and later missions from Jet Propulsion Laboratory and NASA. Eros’s study intersects research by scientists associated with the Smithsonian Institution, Max Planck Institute for Solar System Research, and the International Astronomical Union.

Discovery and Naming

Discovered on 13 August 1898 by C. D. Perrine during observations at Lick Observatory on Mount Hamilton (California), Eros was quickly tracked by teams at Yerkes Observatory, Royal Greenwich Observatory, and Harvard College Observatory; subsequent orbit computations involved mathematicians connected to Royal Astronomical Society and observatories such as Potsdam Observatory. The asteroid received the name derived from the Greek god of love, reflecting classical naming practices codified by the International Astronomical Union; contemporaneous press coverage appeared in outlets like the New York Times and scientific journals published by the Royal Society. Early photometric and astrometric campaigns were coordinated with the United States Naval Observatory and balloon-borne programs influenced by researchers from the Smithsonian Institution.

Orbit and Classification

Eros follows an orbit that crosses the path of Mars and approaches the orbit of Earth, placing it in the Amor group of near-Earth objects catalogued by the Minor Planet Center and characterized under taxonomies developed at the Jet Propulsion Laboratory and by researchers at the Planetary Science Institute. Its semimajor axis and eccentricity were refined through astrometry by teams at Palomar Observatory, European Southern Observatory, and the Cerro Tololo Inter-American Observatory; orbit determinations utilized perturbation models from work by scholars affiliated with Caltech and the Massachusetts Institute of Technology. Close-approach predictions involve dynamics studied within the frameworks established at the Max Planck Institute for Astrophysics and simulation efforts sponsored by the European Space Agency and NASA.

Physical Characteristics

Eros is an elongated S-type asteroid whose composition was constrained through spectroscopy by researchers at Mount Wilson Observatory, Keck Observatory, and the Very Large Telescope; these studies linked mineralogy to ordinary chondrite meteorites curated at the Natural History Museum, London and the Smithsonian Institution National Museum of Natural History. High-resolution imaging from missions and ground-based adaptive optics at Mauna Kea Observatory and Gemini Observatory revealed a bilobed, heavily cratered shape with regolith processes studied by teams from Brown University, University of Arizona, and University of Colorado Boulder. Density and porosity estimates benefitted from work conducted at Jet Propulsion Laboratory and models advanced by researchers at the University of California, Berkeley and Stanford University; thermal inertia and Yarkovsky effects were analyzed in collaboration with scientists at the University of Bern and University of Pisa.

Exploration and Observations

Eros was the primary target of the NEAR Shoemaker mission developed by NASA and managed by Jet Propulsion Laboratory, with instruments provided by institutions including Johns Hopkins University Applied Physics Laboratory, German Aerospace Center, and University of California, Los Angeles. NEAR Shoemaker performed flybys and an orbital campaign delivering imagery and compositional data that were later interpreted by teams from Cornell University, Massachusetts Institute of Technology, and the University of Washington; the spacecraft’s final landing was celebrated by agencies such as NASA and observations coordinated with the International Astronomical Union. Subsequent radar observations were performed by facilities at Arecibo Observatory and Goldstone Deep Space Communications Complex, while follow-up spectroscopic monitoring involved European Southern Observatory and amateur networks affiliated with the American Astronomical Society and International Dark-Sky Association.

Potential Hazard and Future Missions

Eros’s orbit has been monitored by the Minor Planet Center, Jet Propulsion Laboratory’s Center for Near Earth Object Studies, and planetary defense programs at NASA and European Space Agency for impact probability assessments similar to protocols established after events studied by the B612 Foundation and workshops at the International Academy of Astronautics. While not classified as an imminent impactor, Eros figures into risk matrices used by United Nations Office for Outer Space Affairs-endorsed efforts and into resource-assessment studies considered by private firms like Planetary Resources and research groups at Colorado School of Mines. Proposed future missions by agencies such as NASA, ESA, and collaborations involving JAXA and Roscosmos include reconnaissance concepts, sample-return studies modeled on Hayabusa and OSIRIS-REx, and in-situ investigations informed by NEAR Shoemaker’s legacy and planning at institutes like Caltech and MIT.

Category:Minor planets