Gravitational Field of the Moon

1966 ◽  
pp. 1-8
Author(s):  
Dirk Brouwer
Keyword(s):  
Nature ◽  
1966 ◽  
Vol 212 (5059) ◽  
pp. 271-271 ◽  
Author(s):  
C. L. GOUDAS ◽  
Z. KOPAL ◽  
Z. KOPAL
Keyword(s):  

1997 ◽  
Vol 165 ◽  
pp. 281-286
Author(s):  
Natasha Petrova

The study of lunar rotation has attracted considerable interest with the advent of the epoch of exploration of the Solar system by space technology. A series of works on an investigation of the lunar gravitational field carried out with the help of artificial lunar satellites have greatly advanced our possibility for that study. The problem concerning the landing on the lunar surface of spacecraft, and the creation of durable lunar bases, impose heavy demands on the accuracy of theoretical description of orbital and rotational motion of the Moon.The development of the observational technology with the help of radio-and laser ranging (LLR) provides at the present time measurements of the distance to a given point on the Moon with an accuracy of about 2 cm, probably improved in the future to about 5mm (Banerdt, 1995). By using differential VLBI measurement with extragalactic radio sources angularly near the Moon, it should be possible to obtain routine estimates of angular position of the beacon to 0.1 mas from each observation (Baudry, 1995). Therefore, combining VLBI and LLR techniques will provide a means of achieving new objectives, and that calls for the development of the theories adequate to an accuracy for observations.


1941 ◽  
Vol 3 (10) ◽  
pp. 691-729 ◽  

Vito Volterra was born at Ancona on 3 May 1860, the only child of Abramo Volterra and Angelica Almagià. When he was three months old the town was besieged by the Italian army and the infant had a narrow escape from death, his cradle being actually destroyed by a bomb which fell near it. When he was barely two years old his father died, leaving the mother, now almost penniless, to the care of her brother Alfonso Almagia, an employee of the Banca Nazionale, who took his sister into his house and was like a father to her child. They lived for some time in Terni, then in Turin, and after that in Florence, where Vito passed the greater part of his youth and came to regard himself as a Florentine. At the age of eleven he began to study Bertrand’s Arithmetic and Legendre’s Geometry , and from this time on his inclination to mathematics and physics became very pronounced. At thirteen, after reading Jules Verne’s scientific novel Around the Moon , he tried to solve the problem of determining the trajectory of a projectile in the combined gravitational field of the earth and moon: this is essentially the ‘restricted Problem of Three Bodies’, and has been the subject of extensive memoirs by eminent mathematicians both before and after the youthful Volterra’s effort: his method was to partition the time into short intervals, in each of which the force could be regarded as constant, so that the trajectory was obtained as a succession of small parabolic arcs. Forty years later, in 1912, he demonstrated this solution in a course of lectures given at the Sorbonne.


Science ◽  
2019 ◽  
Vol 364 (6445) ◽  
pp. eaat2965 ◽  
Author(s):  
L. Iess ◽  
B. Militzer ◽  
Y. Kaspi ◽  
P. Nicholson ◽  
D. Durante ◽  
...  

The interior structure of Saturn, the depth of its winds, and the mass and age of its rings constrain its formation and evolution. In the final phase of the Cassini mission, the spacecraft dived between the planet and its innermost ring, at altitudes of 2600 to 3900 kilometers above the cloud tops. During six of these crossings, a radio link with Earth was monitored to determine the gravitational field of the planet and the mass of its rings. We find that Saturn’s gravity deviates from theoretical expectations and requires differential rotation of the atmosphere extending to a depth of at least 9000 kilometers. The total mass of the rings is (1.54 ± 0.49) × 1019 kilograms (0.41 ± 0.13 times that of the moon Mimas), indicating that the rings may have formed 107 to 108 years ago.


The Moon ◽  
1972 ◽  
Vol 3 (4) ◽  
pp. 388-402 ◽  
Author(s):  
William H. Michael ◽  
W. Thomas Blackshear

1965 ◽  
Vol 21 ◽  
pp. 67-79
Author(s):  
Harold Jeffreys

The author discusses various determinations of zonal and tesseral harmonics of the Earth's gravitational field, the values of the solar parallax, and the constants related to the figure of the Moon and its motion.


Sign in / Sign up

Export Citation Format

Share Document