154 Bertha

Discovery[1]
Discovered by| P. M. Henry
Discovery date| 4 November 1875
Designations

MPC designation

| (154) Bertha
Pronunciation| /ˈbɜːrθə/[2]

Alternative designations

| A875 VD
Minor planet category| Main belt
Orbital characteristics[3][4]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc| 130.75 yr (47758 d)
|{{{apsis}}}|helion}}| 3.44 astronomical unit|AU (515.21 Gm)
|{{{apsis}}}|helion}}| 2.95 AU (441.30 Gm)

Semi-major axis

| 3.20 AU (478.26 Gm)
Eccentricity| 0.077261
Orbital period| 5.72 years (2,087.9 d)
Average Orbital speed| 16.63 km/s
Mean anomaly| 125.046°
Mean motion| 0° 10m 20.734s / day
Inclination| 20.9724°
Longitude of ascending node| 36.7441°

|{{{apsis}}}|helion}}

| 159.722°
Earth MOID| 1.95 AU (291.94 Gm)
Jupiter MOID| 1.53 AU (229.03 Gm)
TJupiter| 3.087
Physical characteristics
Dimensions| 184.93±3.6 km[3]
186.85±1.83 km[5]
Mass| (9.19±5.20)×1018 kg[5]
Mean density| 2.69±1.52 g/cm3[5]

Equatorial surface gravity

| 0.0517 m/s²

Equatorial escape velocity

| 0.0978 km/s
Rotation period| 25.224 h (1.0510 d)[3][6]
Geometric albedo| 0.0480±0.002[3]
0.0483 ± 0.0107[7]
Physics| ~156 K

Spectral type

| C[7]
Absolute magnitude (H)| 7.58,[3] 7.530[7]

154 Bertha is a main-belt asteroid. It was discovered by the French brothers Paul Henry and Prosper Henry on 4 November 1875, but the credit for the discovery was given to Prosper. It is probably named after Berthe Martin-Flammarion, sister of the astronomer Camille Flammarion.[8]

Observations performed at the Palmer Divide Observatory in Colorado Springs, Colorado in during 2007 produced a light curve with a period of 22.30 ± 0.03 hours and a brightness range of 0.10 ± 0.02 in magnitude. A 1998 measurement gave a value of 27.6 hours, which doesn't fit the PDO data.[9] In 2011, observations from the Organ Mesa Observatory in Las Cruces, New Mexico were used to determine a rotation period of 25.224 ± 0.002 hours with a brightness variability of 0.10 ± 0.01 magnitude, ruling out previous studies.[6]

This is classified as a C-type asteroid[7] and it has an estimated diameter of about 187 km.[5]

## References

1. ↑ "Discovery Circumstances: Numbered Minor Planets". International Astronomical Union - Minor Planet Center. https://minorplanetcenter.net//iau/lists/NumberedMPs000001.html.
2. ↑ Bertha (3rd ed.), Oxford University Press, September 2005, http://oed.com/search?searchType=dictionary&q=Bertha (Subscription or UK public library membership required.)
3. ↑ 3.0 3.1 3.2 3.3 3.4 Yeomans, Donald K., "154 Bertha", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=154, retrieved 12 May 2016.
4. ↑ "The Asteroid Orbital Elements Database". Lowell Observatory. http://ftp.lowell.edu/pub/elgb/astorb.html.
5. ↑ 5.0 5.1 5.2 5.3 Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: pp. 98–118, doi:10.1016/j.pss.2012.03.009, Bibcode: 2012P&SS...73...98C. See Table 1.
6. ↑ 6.0 6.1 Pilcher, Frederick (April 2012), "Rotation Period Determinations for 31 Euphrosyne, 65 Cybele, 154 Bertha 177 Irma, 200 Dynamene, 724 Hapag, 880 Herba, and 1470 Carla", The Minor Planet Bulletin 39 (2): pp. 57–60, Bibcode: 2012MPBu...39...57P.
7. ↑ 7.0 7.1 7.2 7.3 Pravec, P. et al. (May 2012), "Absolute Magnitudes of Asteroids and a Revision of Asteroid Albedo Estimates from WISE Thermal Observations", Asteroids, Comets, Meteors 2012, Proceedings of the conference held May 16–20, 2012 in Niigata, Japan (1667), Bibcode: 2012LPICo1667.6089P. See Table 4.
8. ↑ Schmadel, Lutz D. (2012), Dictionary of Minor Planet Names (6th ed.), Springer, p. 27, ISBN 3642297188, https://books.google.com/books?id=aeAg1X7afOoC&pg=PA27.
9. ↑ Warner, Brian D. (September 2007), "Asteroid Lightcurve Analysis at the Palmer Divide Observatory", The Minor Planet Bulletin, Bibcode: 2007MPBu...34...72W.

## External links

* Lightcurve plot of 154 Bertha[Usurped!], Palmer Divide Observatory, B. D. Warner (2007)
* Asteroid Lightcurve Database (LCDB), query form (info )
* Dictionary of Minor Planet Names, Google books
* Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
* Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
* 154 Bertha at AstDyS-2, Asteroids—Dynamic Site
* Ephemeris * Observation prediction * Orbital info * Proper elements * Observational info
* 154 Bertha at the JPL Small-Body Database
* Close approach * Discovery * Ephemeris * Orbit diagram * Orbital elements * Physical parameters

* v
* t
* e

Minor planets navigator

* 153 Hilda
* 154 Bertha
* 155 Scylla

* v
* t
* e

Small Solar System bodies

Minor planets|

* Designation
* Groups
* List
* Moon
* Meanings of names

Asteroid|

* Aten asteroid
* Asteroid belt
* Family
* Jupiter trojan
* Near-Earth
* Spectral types

Distant minor planet|

* Centaur
* Damocloid
* Neptune trojan
* Trans-Neptunian object
* Detached
* Kuiper belt
* Oort cloud
* Scattered disc

Comets|

* Extinct
* Great
* Halley-type
* Hyperbolic
* Long-period
* Lost
* Main-belt
* Near-parabolic
* Periodic
* Sungrazing

Other|

* Meteoroids

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/154 Bertha. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:154_Bertha&oldid=4559056"
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template