(528381) 2008 ST291

Last updated

(528381) 2008 ST291
2008 ST291-orbit.png
Orbit of (528381) 2008 ST291
Discovery [1] [2]
Discovered by M. E. Schwamb
M. E. Brown
D. L. Rabinowitz
Discovery site Palomar Obs.
Discovery date24 September 2008
Designations
(528381) 2008 ST291
2008 ST291
TNO  · SDO
res 1:6 [3]
Orbital characteristics [4]
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 3
Observation arc 9.27 yr (3,385 d)
Aphelion 157.437 AU (23.5522 Tm)
Perihelion 42.3114440 AU (6.32970193 Tm)
99.8742972 AU (14.94098220 Tm)
Eccentricity 0.5763530
998.30 yr (364,629 d)
23.349°
0° 0m 3.6s / day
Inclination 20.758°
330.97°
324.65°
Physical characteristics
549  km (est.) [5]
584 km(est.) [3]
612 km [6] [7] [a]
345–773 km [7] [b]
0.09 (assumed) [3] [5]
22.24 [6]
4.4 [1] [4]
4.3 [6]
4.6 [5]

    (528381) 2008 ST291, provisional designation 2008 ST291, is a 1:6 resonant trans-Neptunian object located in the outermost region of the Solar System that takes almost a thousand years to complete an orbit around the Sun. [5] It was discovered on 24 September 2008 by American astronomers Megan Schwamb, Michael Brown and David Rabinowitz at the Palomar Observatory in California, with no known earlier precovery images. [1]

    Contents

    Numbering and naming

    This minor planet was numbered by the Minor Planet Center on 18 May 2019 ( M.P.C. 114657). [8] As of 2019, it has not been named. [1]

    Orbit and classification

    Orbit comparison of 2008 ST291, Pluto and Neptune 2008ST291-orbit.png
    Orbit comparison of 2008 ST291, Pluto and Neptune

    2008 ST291 is located at the 1:6 Neptune resonance of 99 AU meaning that it completes roughly 1 orbit for every 6 orbits Neptune makes. [3] It orbits the Sun at a distance of 42.3–157.5  AU once every 998 years and 4 months (semi-major axis of 99.89 AU). Its orbit has an eccentricity of 0.58 and an inclination of 21° with respect to the ecliptic. [4] Currently located at 60.9  AU from the Sun, [6] the object came to perihelion in 1954. [4]

    Physical characteristics

    Based on an absolute magnitude of 4.4, [1] 2008 ST291 is estimated by the Johnston's Archive to be about 584 kilometres (363 mi) in diameter, assuming a typical albedo of 0.09 for trans-Neptunian objects. [3] Astronomer Mike Brown estimates a slightly smaller 549 km from the same albedo and a fainter 4.6 magnitude. [5] The Asteroid Dynamic Site records a brighter 4.3 magnitude, which calculates to 612 km using the same albedo (and same formula as Johnston's); using the average of these magnitudes and a standard assumed minor planet albedo range of 0.25 ~ 0.05, possible sizes of 345 to 773 km are produced.

    See also

    Notes

    1. ↑ Based on AstDyS magnitude and same 0.09 albedo as Brown and Johnston, using Bruton formula
    2. ↑ Based on averaged magnitude of 4.433 and typically assumed minor planet albedo range of 0.05 ~ 0.25, using Bruton formula

    References

    This page is based on this Wikipedia article
    Text is available under the CC BY-SA 4.0 license; additional terms may apply.
    Images, videos and audio are available under their respective licenses.