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46-614: The rotational axis of the Moon passes through Shackleton, near the rim. The crater is 21 km (13 miles) in diameter and 4.2 km (2.6 miles) deep. From the Earth, it is viewed edge-on in a region of rough, cratered terrain. It is located within the South Pole–Aitken basin on a massif . The rim is slightly raised about the surrounding surface and it has an outer rampart that has been only lightly impacted. No significant craters intersect

92-644: A cometary impact on the Moon would lie permanently frozen on or below the surface. However, the surface albedo of the crater floor matches the lunar far-side, suggesting that there is no exposed surface ice. This crater was named after Ernest Shackleton , an Anglo-Irish explorer of Antarctica from 1901 until his death in 1922. The name was officially adopted by the International Astronomical Union in 1994. Nearby craters of note include Shoemaker , Haworth , de Gerlache , Sverdrup , Slater , and Faustini . Somewhat farther away, on

138-615: A large mass of material had been identified deep within the crater. Chang'e 6 aims to collect sample from this crater, specifically within the Apollo basin . The existence of a giant far side basin was suspected as early as 1962 based on early Soviet probe images (namely Luna 3 and Zond 3 ), but it was not until wide-field photographs taken by the US Lunar Orbiter program became available in 1966-7 that geologists recognized its true size. Laser altimeter data obtained during

184-409: A commodity that is expensive to deliver directly from the Earth. This crater has also been proposed as a future site for a large infrared telescope . The low temperature of the crater floor makes it ideal for infrared observations, and solar cells placed along the rim could provide near-continuous power to the observatory. About 120 kilometers from the crater lies the 5-km tall Malapert Mountain ,

230-443: A dihydrate (melting point 97 °C). Protein crystals commonly have as much as 50% water content. Molecules are also labeled as hydrates for historical reasons not covered above. Glucose , C 6 H 12 O 6 , was originally thought of as C 6 (H 2 O) 6 and described as a carbohydrate . Hydrate formation is common for active ingredients . Many manufacturing processes provide an opportunity for hydrates to form and

276-566: A location called "Shackleton Heights", where his album's back-story takes place. Shackleton was the landing site for the Korean movie The_Moon (2024 film) South Pole%E2%80%93Aitken basin The South Pole–Aitken basin (SPA Basin, / ˈ eɪ t k ɪ n / ) is an immense impact crater on the far side of the Moon . At roughly 2,500 km (1,600 mi) in diameter and between 6.2 and 8.2 km (3.9–5.1 mi) deep, it

322-506: A low-velocity projectile around 200 km in diameter (compare to the 10 km diameter Chicxulub impactor ) that hit at a low angle (about 30 degrees or less), and hence did not dig very deeply into the Moon. Putative evidence for this comes from the high elevations north-east of the rim of the South Pole–Aitken basin that might represent ejecta from such an oblique impact. The impact theory would also account for magnetic anomalies on

368-439: A metal center or that have crystallized with the metal complex. Such hydrates are also said to contain water of crystallization or water of hydration . If the water is heavy water in which the constituent hydrogen is the isotope deuterium , then the term deuterate may be used in place of hydrate . A colorful example is cobalt(II) chloride , which turns from blue to red upon hydration , and can therefore be used as

414-456: A peak that is perpetually visible from the Earth , and which could serve as a radio relay station when suitably equipped. In 2006, NASA named the rim of Shackleton as a potential candidate for its lunar outpost , originally slated to be up and running by 2020 and continuously staffed by a crew by 2024. The location would promote self-sustainability for lunar residents, as perpetual sunlight on

460-463: A water indicator. The notation " hydrated compound ⋅ n H 2 O ", where n is the number of water molecules per formula unit of the salt, is commonly used to show that a salt is hydrated. The n is usually a low integer , though it is possible for fractional values to occur. For example, in a monohydrate n  = 1, and in a hexahydrate n  = 6. Numerical prefixes mostly of Greek origin are: A hydrate that has lost water

506-438: Is methane hydrate (also known as gas hydrate, methane clathrate, etc.). Nonpolar molecules such as methane can form clathrate hydrates with water, especially under high pressure. Although there is no hydrogen bonding between water and guest molecules when methane is the guest molecule of the clathrate, guest–host hydrogen bonding often forms when the guest is a larger organic molecule such as tetrahydrofuran . In such cases

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552-439: Is chloral hydrate , CCl 3 −CH(OH) 2 , which can be formed by reaction of water with chloral , CCl 3 −CH=O . Many organic molecules, as well as inorganic molecules, form crystals that incorporate water into the crystalline structure without chemical alteration of the organic molecule ( water of crystallization ). The sugar trehalose , for example, exists in both an anhydrous form ( melting point 203 °C) and as

598-527: Is almost always available for conversion into electricity using solar panels , potentially making them good locations for future Moon landings . The temperature at this site is also more favorable than at more equatorial latitudes as it does not experience the daily temperature extremes of 100 °C when the Sun is overhead, to as low as −150 °C during the lunar night. While scientific experiments performed by Clementine and Lunar Prospector could indicate

644-610: Is one of the largest known impact craters in the Solar System . It is the largest, oldest, and deepest basin recognized on the Moon . It is estimated that it was formed approximately 4.2 to 4.3 billion years ago, during the Pre-Nectarian epoch (with radiometric dating of lunar zircons proposed to originate from the basin suggesting a precise age of 4.338 billion years ). It was named for two features on opposite sides of

690-411: Is possible that the crash did not excavate deeply enough into the regolith to liberate significant quantities of water vapor. From Earth-based radar and spacecraft images of the crater edge, Shackleton appears to be relatively intact; much like a young crater that has not been significantly eroded from subsequent impacts. This may mean that the inner sides are relatively steep, which may make traversing

736-427: Is referred to as an anhydride ; the remaining water, if any exists, can only be removed with very strong heating. A substance that does not contain any water is referred to as anhydrous . Some anhydrous compounds are hydrated so easily that they are said to be hygroscopic and are used as drying agents or desiccants . In organic chemistry, a hydrate is a compound formed by the hydration, i.e. "Addition of water or of

782-529: The Clementine mission . This interpretation, however, is not universally agreed upon within the scientific community. Radar images of the crater at a wavelength of 13 cm show no evidence for water ice deposits. Optical imaging inside the crater was done for the first time by the Japanese lunar orbiter spacecraft Kaguya in 2007. It did not have any evidence of significant amount of water ice, down to

828-526: The alternate history television drama series For All Mankind . In the program, astronauts in a fictionalized version of the Apollo 15 mission land near Shackleton in 1971 and discover water ice in the crater walls. Later, the United States and the Soviet Union establish competing, crewed bases next to the crater to take advantage of the ice for drinking, oxygen and other uses. Shackleton

874-575: The Apollo 15 and 16 missions showed that the northern portion of this basin was very deep, but since these data were only available along the near-equatorial ground tracks of the orbiting command and service modules , the topography of the rest of the basin remained unknown. The geologic map showing the northern half of this basin and with its edge depicted was published in 1978 by the United States Geological Survey . Little

920-581: The Clementine mission. Most recently, the composition of this basin has been further constrained by the analysis of data obtained from a gamma-ray spectrometer that was on board the Lunar Prospector mission. The South Pole–Aitken basin is the largest, deepest and oldest basin recognized on the Moon. The lowest elevations of the Moon (about −9000 m) are located within the South Pole–Aitken basin. The Moon's tallest mountains are found around

966-479: The Lunar Prospector mission demonstrate that the inner walls of Shackleton are similar in reflective characteristics to those of some sunlit craters. In particular, the surroundings appear to contain a significant number of blocks in its ejecta blanket, suggesting that its radar properties are a result of surface roughness, and not ice deposits, as was previously suggested from a radar experiment involving

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1012-438: The Moon. Hydrate In chemistry , a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understood. Hydrates are inorganic salts "containing water molecules combined in a definite ratio as an integral part of the crystal " that are either bound to

1058-422: The basin's rim – they have summit elevations of up to 8500 m and base-to-peak heights of up to 7000 m. Because of this basin's great size, the crust at this locale is expected to be thinner than typical as a result of the large amount of material that was excavated due to an impact. Crustal thickness maps constructed using the Moon's topography and gravity field imply a thickness of about 30 km beneath

1104-479: The basin: the lunar South Pole at one end and the crater Aitken on the northern end. The outer rim of this basin can be seen from Earth as a huge mountain chain located on the Moon's southern limb, sometimes informally called "Leibnitz mountains". On 3 January 2019, the Chang'e 4 , a Chinese spacecraft, landed in the basin, specifically within a crater called Von Kármán . In May 2019, scientists announced that

1150-459: The bolide ought to have excavated vast amounts of mantle materials from depths as great as 200 km below the surface. However, observations thus far do not favor a mantle composition for this basin and crustal thickness maps seem to indicate the presence of about 10 kilometers of crustal materials beneath this basin's floor. This has suggested to some that the basin was not formed by a typical high-velocity impact, but may instead have been formed by

1196-500: The crater Shackleton. At the end of this mission in July 1999, the spacecraft was crashed into the nearby crater Shoemaker in the hope of detecting from Earth-based telescopes an impact-generated plume containing water vapor. The impact event did not produce any detectable water vapor, and this may be an indication that the hydrogen is not in the form of hydrated minerals , or that the impact site did not contain any ice. Alternatively, it

1242-489: The eastern hemisphere of the lunar near side, are the larger craters Amundsen and Scott , named after two other early explorers of the Antarctic continent. From the perspective of the Earth , this crater lies along the southern limb of the Moon, making observation difficult. Detailed mapping of the polar regions and farside of the Moon did not occur until the advent of orbiting spacecraft. Shackleton lies entirely within

1288-401: The elements of water (i.e. H and OH) to a molecular entity". For example: ethanol , CH 3 −CH 2 −OH , is the product of the hydration reaction of ethene , CH 2 =CH 2 , formed by the addition of H to one C and OH to the other C, and so can be considered as the hydrate of ethene. A molecule of water may be eliminated, for example, by the action of sulfuric acid . Another example

1334-403: The first lunar sample return from Apollo Basin on the far side of the Moon . This is China's second lunar sample return mission, the first was achieved by Chang'e 5 from the lunar near side four years earlier. It also carried a Chinese rover called Jinchan to conduct infrared spectroscopy of lunar surface and imaged Chang'e 6 lander on lunar surface. The lander-ascender-rover combination

1380-439: The floor of the basin has slightly elevated abundances of iron, titanium, and thorium. In terms of mineralogy, the basin floor is much richer in clinopyroxene and orthopyroxene than the surrounding highlands, which are largely anorthositic . Several possibilities exist for this distinctive chemical signature: one is that it might simply represent lower crustal materials that are somewhat richer in iron, titanium and thorium than

1426-615: The floor of this basin, in comparison to 60–80 km around it and the global average of about 50 km. The composition of the basin, as estimated from the Galileo , Clementine , and Lunar Prospector missions, appears to be different from typical highland regions. Most importantly, none of the samples obtained from the American Apollo and Russian Luna missions, nor the handful of identified lunar meteorites , have comparable compositions. The orbital data indicate that

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1472-555: The image resolution of 10 m per pixel. On November 15, 2008, a 34-kg probe made a hard landing near the crater. The Moon Impact Probe (MIP) was launched from the Indian Chandrayaan-1 spacecraft and reached the surface 25 minutes later. The probe carried a radar altimeter, video imaging system, and a mass spectrometer, which detected the presence of water during the descent. Some sites along Shackleton's rim receive almost constant illumination. At these locales sunlight

1518-444: The presence of water in the polar craters, the current evidence is far from definitive. There are doubts among scientists as to whether or not the hydrogen is in the form of ice, as well as to the concentration of this "ore" with depth below the surface. Resolution of this issue will require future missions to the Moon. The potential presence of water suggests that the crater floor could be "mined" for deposits of hydrogen in water form,

1564-614: The rim of the crater are almost continually illuminated by sunlight, spending about 80–90% of each lunar orbit exposed to the Sun . Continuously illuminated mountains have been termed peaks of eternal light and have been predicted to exist since the early nineteenth century. The shadowed portion of the crater was imaged with the Terrain Camera of the Japanese SELENE spacecraft using the illumination of sunlight reflected off

1610-436: The rim of the immense South Pole-Aitken basin , which is one of the largest known impact formations in the Solar System . This basin is over 12 kilometers deep, and an exploration of its properties could provide useful information about the lunar interior. A neutron spectrometer on board the Lunar Prospector spacecraft detected enhanced concentrations of hydrogen close to the northern and southern lunar poles, including

1656-463: The rim, and it is sloped about 1.5° toward the direction 50–90° from the Earth. The age of the crater is about 3.6 billion years and it has been in the proximity of the south lunar pole for at least the last two billion years. Because the orbit of the Moon is tilted only 1.5° from the ecliptic , the interior of this crater lies in perpetual darkness. Estimates of the area in permanent shadow were obtained from Earth-based radar studies. Peaks along

1702-416: The rim. The interior of the crater consists of a symmetrical 30° slope that leads down to a 6.6 km (4.1 miles) diameter floor. The handful of craters along the interior span no more than a few hundred meters. The bottom is covered by an uneven mound-like feature that is 300 to 400 m (980–1,310 ft) thick. The central peak is about 200 m (660 ft) in height. The continuous shadows in

1748-427: The sides relatively difficult for a robotic vehicle. In addition, it is possible that the interior floor might not have collected a significant quantity of volatiles since its formation. However other craters in the vicinity are considerably older, and may contain significant deposits of hydrogen , possibly in the form of water ice. (See Shoemaker (lunar crater) , for example.) Radar studies preceding and following

1794-451: The south polar craters cause the floors of these formations to maintain a temperature that never exceeds about 100 K (−173 °C; −280 °F). For Shackleton, the average temperature was determined to be about 90 K (−183 °C; −298 °F), reaching 88 K at the crater floor. Under these conditions, the estimated rate of loss from any ice in the interior would be 10 to 10 m/s. Any water vapor that arrives here following

1840-469: The south pole would provide energy for solar panels. Furthermore, the shadowed polar regions are believed to contain the frozen water necessary for human consumption and could also be harvested for fuel manufacture. The crater is a major landing site candidate for the Artemis program and could be explored by a crew starting in 2026 with a possible first lunar outpost in 2028. Shackleton plays prominently in

1886-412: The state of hydration can be changed with environmental humidity and time. The state of hydration of an active pharmaceutical ingredient can significantly affect the solubility and dissolution rate and therefore its bioavailability . Clathrate hydrates (also known as gas hydrates, gas clathrates, etc.) are water ice with gas molecules trapped within; they are a form of clathrate . An important example

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1932-400: The upper crust; another is that the composition reflects the widespread distribution of ponds of iron-rich basalts , similar to those that make up the lunar maria ; alternatively, the rocks in the basin could contain a component from the lunar mantle if the basin excavated all the way through the crust; and, finally, it is possible that a large portion of the lunar surface surrounding the basin

1978-561: Was also the site of the first lunar base in Mass Effect . It was chosen as a location due to its hypothesised water ice deposits. Shackleton was the location for the site of the Chinese National Space Agency moonbase Guang Han Gong-1 in the fictional podcast series Transmissions from Colony One . Pusher (musician) , in his album published in late September 2023 named "King of the Moon", heavily references

2024-432: Was known about the basin until the 1990s, when the spacecraft Galileo and Clementine visited the Moon. Multispectral images obtained from these missions showed that this basin contains more FeO and TiO 2 than typical lunar highlands, and hence has a darker appearance. The topography of the basin was mapped in its entirety for the first time using altimeter data and the analysis of stereo image pairs taken during

2070-483: Was melted during the impact event, and differentiation of this impact melt sheet could have given rise to additional geochemical anomalies. Complicating the matter is the possibility that several processes have contributed to the basin's anomalous geochemical signature. Ultimately, the origin of the anomalous composition of the basin is not known with certainty and will likely require a sample return mission to determine. China sent Chang'e 6 on 3 May 2024, which conducted

2116-555: Was separated with the orbiter and returner before landing on 1 June 2024 at 22:23 UTC. It landed on the Moon's surface on 1 June 2024. The ascender was launched back to lunar orbit on 3 June 2024 at 23:38 UTC, carrying samples collected by the lander, and later completed another robotic rendezvous and docking in lunar orbit. The sample container was then transferred to the returner, which landed on Inner Mongolia on 25 June 2024, completing China's far side extraterrestrial sample return mission. Simulations of near vertical impacts show that

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