(3990) Heimdal Outer Main-belt Asteroid
Discovered on 25 September 1987 by P. Jensen at Brorfelde.
Where Heimdal is today
Seen from above the solar system on 2026-10-14: Heimdal is 3.21 au from the Sun and 2.53 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 3990 |
| Provisional designation | 1987 SO3 |
| Orbit class | Outer Main-belt Asteroid |
| Diameter | 35.7 km (#1,128 largest of 17,440 named asteroids with a measured size) |
| Albedo | 0.0670 |
| Rotation period | 45.8 hours |
| Absolute magnitude (H) | 11.01 |
| Orbital period | 7.83 years |
| Semi-major axis | 3.94 au |
| Perihelion – aphelion | 2.99 – 4.90 au |
| Eccentricity | 0.242 |
| Inclination | 9.50° |
| Closest distance between its orbit and Earth's (MOID) | 2.00 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.
Also discovered on 25 September 1987
More named asteroids discovered by P. Jensen
- (3459) Bodil
- (3782) Celle
- (3796) Lene
- (3830) Trelleborg
- (3858) Dorchester
- (3864) Soren
- (3948) Bohr
- (3956) Caspar
- (3989) Odin
- (4059) Balder
- (4088) Baggesen
- (4092) Tyr
← (3989) Odin · (3991) Basilevsky →