# 746 Marlu
**746 Marlu** (provisional designations A913 EJ and 1913 QY) is a large asteroid orbiting the Sun in the main portion of the asteroid belt between Mars and Jupiter. It was discovered on 1 March 1913 at [Heidelberg](https://www.edgepedia.org/heidelberg) by F. Kaiser. Marlu completes one revolution every 2,010 days (5.50 years), with a moderately eccentric and inclined orbit that carries it from 2.38 AU at perihelion to 3.85 AU at aphelion. It is not classified by NASA JPL as a potentially hazardous object, as the closest point between its orbit and [Earth's orbit](https://www.edgepedia.org/earths-orbit) is 1.41 AU.
| Key fact | Detail |
|---|---|
| Discovery | 1 March 1913, Heidelberg, by F. Kaiser; provisional designations A913 EJ and 1913 QY[1](https://astronomia.zcu.cz/planety/planetka-746) |
| Orbit | Semi-major axis 3.111 AU, eccentricity 0.236, inclination 17.48°, period 5.49 years (about 2,004 days)[2](https://www.spacereference.org/asteroid/746-marlu-a913-ej/shape) |
| Distance from the Sun | Perihelion 2.38 AU, aphelion 3.85 AU[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej) |
| Hazard status | Not a near-Earth object and not a potentially hazardous object; its orbit stays at least 1.41 AU from Earth's orbit[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej) |
## Orbit and classification
Marlu orbits the Sun in the main portion of the asteroid belt between Mars and Jupiter, completing one revolution every 2,010 days (5.50 years).[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej) Its orbit is moderately eccentric and inclined, carrying it from 2.38 AU at perihelion to 3.85 AU at aphelion.[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej)
Because its orbit does not bring it near Earth, NASA JPL has not classified Marlu as a potentially hazardous object, and orbital simulations by JPL's CNEOS show no close approaches to Earth.[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej) The closest point between its orbit and Earth's orbit is 1.41 AU.[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej)
## Physical properties
Three infrared surveys have measured Marlu's size and reflectivity: the [Infrared Astronomical Satellite](https://www.edgepedia.org/infrared-astronomical-satellite) (IRAS), the Japanese Akari satellite, and NASA's NEOWISE mission from the [Wide-field Infrared Survey Explorer](https://www.edgepedia.org/wide-field-infrared-survey-explorer) (WISE).
## Rotation and shape
A convex shape model from the DAMIT database, maintained by the Astronomical Institute of Charles University in Prague, gives a sidereal spin period of 7.78887 hours and two possible spin-axis solutions at ecliptic coordinates (202.0°, −66.0°) and (64.0°, −27.0°).[2](https://www.spacereference.org/asteroid/746-marlu-a913-ej/shape)
## Observation record
Marlu's orbit is determined from observations dating back to 12 September 1915, with 7,246 observations recorded by the IAU Minor Planet Center; it was last officially observed on 4 July 2023.[3](https://www.spacereference.org/asteroid/746-marlu-a913-ej) The Czech Planety database lists 8,332 observations across 46 oppositions spanning 1915 to 2026.[1](https://astronomia.zcu.cz/planety/planetka-746)
## References
1. [Planetka Marlu (746), Planety, University of West Bohemia](https://astronomia.zcu.cz/planety/planetka-746)
2. [Marlu Shape Model, Space Reference](https://www.spacereference.org/asteroid/746-marlu-a913-ej/shape)
3. [Asteroid Marlu, Space Reference](https://www.spacereference.org/asteroid/746-marlu-a913-ej)
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*Topic: Encyclopedia › Places and geography › Extraterrestrial places › Small bodies of the Solar System › Main-belt asteroids and numbered minor planets › Outer-belt asteroids*
*Initially written Oct 21, 2026 · Edited: Oct 25, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license