Buys-Ballot (crater)
Encyclopedia
Buys-Ballot is an oddly-shaped lunar
crater
that is located on the far side of the Moon
. It lies just to the northwest of the small lunar mare
named Lacus Luxuriae
, and southeast of the crater Freundlich
. Other nearby craters of note are Anderson
to the southwest and Dante
to the northeast.
This formation has a distinctive shape for a crater, having a prominent extension to the south that nearly doubles the dimension compared to the width across the maximum west-east cross-section. It vaguely resembles a pear, with the thinner end to the south and the bulge to the north. Despite the odd shape, this crater has not been significantly eroded and only a few tiny craterlets mark the interior or the rim.
Running down the middle of the crater along its longest dimension is a ridge that divides the southern part in half. This ridge extends as far north as the widest part before coming to an end. The floor at this widest part has been partially resurfaced by basalt
ic lava
, leaving an oval area around the northern edge of the central ridge surrounded by a patch of material with a lower albedo
than the surroundings. The remainder of the interior floor is somewhat rough and irregular, particularly in the southern half.
Attached to the northern end of the crater is another odd formation consisting of the satellite craters Buys-Ballot Y and Z. These two nearly resemble mirror images of each other, being joined down the center by a narrow ridge line and extending nearly twice as far to the north as their individual widths in the east-west direction. The main difference between the two is that there is a concentric formation at the north end of the crater Y. The interior surfaces of both craters are irregular.
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
that is located on the far side of the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
. It lies just to the northwest of the small lunar mare
Lunar mare
The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...
named Lacus Luxuriae
Lacus Luxuriae
Lacus Luxuriae is a small lunar mare on the Moon. It is located at 19.0° N, 176.0° E and is 50 km in diameter....
, and southeast of the crater Freundlich
Freundlich (crater)
Freundlich is a lunar crater that is located on the far side of the Moon. It lies midway between the craters Trumpler to the north-northwest and the irregular Buys-Ballot to the south-southeast. This crater has a circular rim that is more heavily eroded at the northern and southern ends...
. Other nearby craters of note are Anderson
Anderson (crater)
Anderson is a lunar impact crater that is located on the far side of the Moon. It is located to the northwest of the crater Sharonov, and the satellite crater Sharanov X is attached to the southeast rim of Anderson. To the northeast is the peculiar formation Buys-Ballot, and to the east-southeast...
to the southwest and Dante
Dante (crater)
Dante is a lunar crater that is located on the far side of the Moon. It lies in the northern hemisphere exactly opposite the prime meridian facing the Earth. The nearest craters of note are Larmor to the north and Morse to the southeast. To the southwest is the oddly shaped Buys-Ballot.This crater...
to the northeast.
This formation has a distinctive shape for a crater, having a prominent extension to the south that nearly doubles the dimension compared to the width across the maximum west-east cross-section. It vaguely resembles a pear, with the thinner end to the south and the bulge to the north. Despite the odd shape, this crater has not been significantly eroded and only a few tiny craterlets mark the interior or the rim.
Running down the middle of the crater along its longest dimension is a ridge that divides the southern part in half. This ridge extends as far north as the widest part before coming to an end. The floor at this widest part has been partially resurfaced by basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
ic lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...
, leaving an oval area around the northern edge of the central ridge surrounded by a patch of material with a lower albedo
Albedo
Albedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...
than the surroundings. The remainder of the interior floor is somewhat rough and irregular, particularly in the southern half.
Attached to the northern end of the crater is another odd formation consisting of the satellite craters Buys-Ballot Y and Z. These two nearly resemble mirror images of each other, being joined down the center by a narrow ridge line and extending nearly twice as far to the north as their individual widths in the east-west direction. The main difference between the two is that there is a concentric formation at the north end of the crater Y. The interior surfaces of both craters are irregular.
Satellite craters
By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Buys-Ballot.| Buys-Ballot | Latitude | Longitude | Diameter |
|---|---|---|---|
| H | 19.4° N | 179.5° E | 22 km |
| Q | 19.5° N | 172.7° E | 58 km |
| Y | 22.9° N | 174.0° E | 31 km |
| Z | 22.5° N | 174.5° E | 58 km |