Discovery [1] | |
---|---|
Discovered by | J. Palisa |
Discovery site | Austrian Naval Obs. |
Discovery date | 2 November 1875 |
Designations | |
(153) Hilda | |
Pronunciation | /ˈhɪldə/ [2] |
A875 VC; 1935 GD | |
Main belt ( Hilda) | |
Adjectives | Hildian /ˈhɪldiən/ [3] |
Orbital characteristics [1] | |
Epoch 31 July 2016 ( JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 121.05 yr (44215 d) |
Aphelion | 4.5341 AU (678.29 Gm) |
Perihelion | 3.4225 AU (512.00 Gm) |
3.9783 AU (595.15 Gm) | |
Eccentricity | 0.13971 |
7.935 yr (2,898.3 d) 7.94 yr (2898.3 d) | |
51.690 ° | |
0° 7m 27.156s / day | |
Inclination | 7.8249° |
228.16° | |
38.617° | |
Jupiter MOID | 0.569657 AU (85.2195 Gm) |
TJupiter | 3.023 |
Physical characteristics | |
Dimensions | 170.63±3.3 km [1] |
Mass | ~5.2×1018 kg |
Equatorial
escape velocity | ~ 6 m/s |
5.9587 h (0.24828 d) [1] | |
0.0618±0.002 [1] | |
P [4] | |
7.48 [1] | |
Hilda ( minor planet designation: 153 Hilda) is a large asteroid in the outer main belt, with a diameter of 170 km. [1] The spectrum matches that of a P-type asteroid. [4] It was discovered by Johann Palisa on 2 November 1875, from the Austrian Naval Observatory at Pula, now Croatia. [1] The name was chosen by the astronomer Theodor von Oppolzer, who named it after one of his daughters. [5]
Hilda gives its name to an asteroid group called the Hilda group (or Hildas for short). It is not a true asteroid family, since the members are not physically related, but rather share similar orbital elements. The Hildas are locked in a 2:3 orbital resonance with Jupiter; [6] since Jupiter takes 11.9 years to orbit the Sun while Hilda takes 7.9 years, [1] Jupiter orbits the Sun twice for every 3 orbits that Hilda completes. There are over 1,100 other objects known to be in a 2:3 resonance with Jupiter. [6]
The orbital plane of 153 Hilda is inclined at an angle of 7.82° to the plane of the ecliptic. It has an orbital eccentricity (ovalness) of 0.13971. [1] Multiple light curves of the asteroid provide a consistent rotation period of approximately 5.9585 h [7]
Discovery [1] | |
---|---|
Discovered by | J. Palisa |
Discovery site | Austrian Naval Obs. |
Discovery date | 2 November 1875 |
Designations | |
(153) Hilda | |
Pronunciation | /ˈhɪldə/ [2] |
A875 VC; 1935 GD | |
Main belt ( Hilda) | |
Adjectives | Hildian /ˈhɪldiən/ [3] |
Orbital characteristics [1] | |
Epoch 31 July 2016 ( JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 121.05 yr (44215 d) |
Aphelion | 4.5341 AU (678.29 Gm) |
Perihelion | 3.4225 AU (512.00 Gm) |
3.9783 AU (595.15 Gm) | |
Eccentricity | 0.13971 |
7.935 yr (2,898.3 d) 7.94 yr (2898.3 d) | |
51.690 ° | |
0° 7m 27.156s / day | |
Inclination | 7.8249° |
228.16° | |
38.617° | |
Jupiter MOID | 0.569657 AU (85.2195 Gm) |
TJupiter | 3.023 |
Physical characteristics | |
Dimensions | 170.63±3.3 km [1] |
Mass | ~5.2×1018 kg |
Equatorial
escape velocity | ~ 6 m/s |
5.9587 h (0.24828 d) [1] | |
0.0618±0.002 [1] | |
P [4] | |
7.48 [1] | |
Hilda ( minor planet designation: 153 Hilda) is a large asteroid in the outer main belt, with a diameter of 170 km. [1] The spectrum matches that of a P-type asteroid. [4] It was discovered by Johann Palisa on 2 November 1875, from the Austrian Naval Observatory at Pula, now Croatia. [1] The name was chosen by the astronomer Theodor von Oppolzer, who named it after one of his daughters. [5]
Hilda gives its name to an asteroid group called the Hilda group (or Hildas for short). It is not a true asteroid family, since the members are not physically related, but rather share similar orbital elements. The Hildas are locked in a 2:3 orbital resonance with Jupiter; [6] since Jupiter takes 11.9 years to orbit the Sun while Hilda takes 7.9 years, [1] Jupiter orbits the Sun twice for every 3 orbits that Hilda completes. There are over 1,100 other objects known to be in a 2:3 resonance with Jupiter. [6]
The orbital plane of 153 Hilda is inclined at an angle of 7.82° to the plane of the ecliptic. It has an orbital eccentricity (ovalness) of 0.13971. [1] Multiple light curves of the asteroid provide a consistent rotation period of approximately 5.9585 h [7]