{"id":61089,"date":"2024-07-03T14:18:18","date_gmt":"2024-07-03T14:18:18","guid":{"rendered":"https:\/\/www.africa-press.net\/south-sudan\/all-news\/scientists-estimate-moons-finsen-crater-is-3-5-billion-years-old"},"modified":"2024-07-03T14:39:02","modified_gmt":"2024-07-03T14:39:02","slug":"scientists-estimate-moons-finsen-crater-is-3-5-billion-years-old","status":"publish","type":"post","link":"https:\/\/www.africa-press.net\/south-sudan\/all-news\/scientists-estimate-moons-finsen-crater-is-3-5-billion-years-old","title":{"rendered":"Scientists Estimate Moon\u2019s Finsen Crater is 3.5 Billion Years Old"},"content":{"rendered":"

Africa-Press – South-Sudan. <\/strong><\/span>A team of researchers led by a Chinese Academy of Sciences (CAS) professor determined that the absolute model age (AMA), or geologic age, of the Finsen crater on the moon\u2019s far side is around 3.5 billion years.<\/p>\n

A new study to be published in the January 2021 edition of planetary science journal Icarus estimated the AMA crater degradation rate of the lunar Finsen crater.<\/p>\n

The team, led by CAS Prof. Di Kaichang, of the State Key Laboratory of Remote Sensing Sciences, Aerospace Information Research Institute, relied on information obtained by China\u2019s Chang’e-4 probe, which landed on the far side of the moon on January 3, 2019.<\/p>\n

A CAS memo republished by Phys.org on Friday revealed that the team used a digital orthophoto map and digital elevation model data produced by the Chang’e-4 probe to outline a flat and homogeneous area on the Finsen crater\u2019s floor that was later used to manually map out craters nearby.<\/p>\n

Scientists calculated the AMA of the Finsen crater by \u201cfitting the obtained crater size-frequency distribution (CSFD) to standard lunar cratering chronology,\u201d the release stated.<\/p>\n

\u201cBoth cumulative and differential fits revealed an AMA of ~3.5 Ga [billion years], indicating Finsen crater was Imbrium-aged.\u201d<\/p>\n

The crater degradation rate at Finsen, calculated by current depth of the 25 largest craters in the defined area, was found to be around 21 \u00b1 3 meters per billion years.<\/p>\n

Comparatively, \u201chowever, the rate is much slower than that on other airless rocky bodies, for example, average degradation rate on [the asteroid] Vesta is 350 m\/Gyr [billion years], and on [the asteroid] Gaspra is 100-1000 m\/Gyr. One of the most likely reasons is that craters on asteroids are easily degraded or even erased by mass movements caused by impact-induced global seismic shaking.\u201d<\/p>\n

The growth rate of the regolith – the loose layer of dust and rock fragments that sits atop solid rock – at the Chang’e-4 probe landing site was also calculated to be about 3.4 meters per billion years. As solid rock breaks and wears away, the regolith increases in depth.<\/p>\n

The release detailed that the regolith growth rate at the Chang’e-4 probe landing site is greater than that of almost all Apollo mission landing sites – except that of Apollo 16. The release highlighted that this could mean there is \u201ca low weathering resistivity of Finsen crater ejecta to the harsh space environment.\u201d<\/p>\n\r\n