The aim of China’s Chang’e 5 mission is to return samples of lunar soil to Earth by the end of 2020.
Chang’e 5 has landed on the Moon at 43.1°N, 51.8°W on December 1st at 10:11 a.m. EST / 15:11 UT. The mission touched down within a large landing ellipse in the Oceanus Procellarum, about 150 kilometers northeast of the Mons Rümker feature. Word of the successful landing trickled out from the Chinese space agency over China’s state-run CCTV network and social media. See shots from the landing below:
Here's a gif of the Chang'e-5 descent and landing while we wait for the full video footage. There's a hover phase in there, but altitude is impossible to discern. pic.twitter.com/3QFitC0vcC
— Andrew Jones (@AJ_FI) December 1, 2020
The timeline calls for sample collection before lunar sunset over the landing site on December 10th, which will mark the end for the solar-powered lander. The Chinese video-streaming site Bilibili might webcast the sampling attempt starting at 9:00 p.m. EST on December 1st (2:00 UT on December 2nd).
China Launches Ambitious Sample-return Mission to the Moon
A Long March 5 rocket roared to life over the Wenchang Satellite Launch Center in a brilliant predawn night shot today, launching China’s ambitious Chang’e 5 sample return mission to the Moon.
The launch occurred at 3:30 p.m. EST (20:30 Universal Time) on Monday, November 23rd (Tuesday, November 24th local time). As is often the case with high-profile launches, Chinese State Television CGTN broadcast the launch live.
The 8.2-ton (7,400-kilogram) mission includes the 3.8-ton (3,450-kilogram) Chang’e 5 lander, the largest payload China has sent to the Moon to date. The spacecraft aims to bring at least 2 kilograms (4.4 pounds) of lunar soil back to Earth for analysis. This would represent the first return of a sample from the Moon since the Soviet Union’s Luna 24 mission back in 1976, and the largest sample return since the Apollo era.
To accomplish this, China will use a return system very similar to the Apollo crewed missions of the 1960s and 1970s, with a lander, lunar ascent vehicle, orbiting service module, and return capsule.
China National Space Administration officials report that Chang’e 5 is healthy and is in an initial 23.5°-inclination orbit around Earth, prior to firing the Long March upper stage’s engine to head to the Moon. The European Space Agency (ESA) is assisting China with worldwide coverage for the mission. The plan is for Chang’e 5 to enter orbit around the Moon before landing near Mons Rümker in Oceanus Procellarum on the edge of the lunar nearside on or around November 27th.
Chang’e 5 is solar powered and will land around local lunar sunrise, maximizing its time during the lunar day (which lasts two weeks on Earth). It’s also worth noting that Chang’e 5 will experience a partial solar eclipse from its perspective during the November 30th penumbral lunar eclipse of the Moon, though there’s no word as of yet as to whether the team plans to capture the spectacle from the lunar surface.
An Ambitious Plan
After the spacecraft collects and stows a sample of the lunar regolith, the ascent vehicle will launch from the surface of the Moon on or around December 9th, just before lunar sunset over the site. This event will mark the first “lunar launch” in 44 years. The ascent vehicle will then perform an automated rendezvous with the service module in lunar orbit, transfer its precious cargo to the return capsule, then head back home. Its touchdown is set for December 16–17th over Inner Mongolia, the same area where China lands its crewed Shenzhou missions.
Entering Earth’s atmosphere from lunar orbit occurs at a much faster velocity than from a low-altitude Earth orbit, at 11 kilometers per second (25,000 mph) versus 8 km/s. Unlike the Apollo crewed returns, which employed heavy heat shielding for direct reentry, Chang’e 5 will skip off of Earth’s atmosphere one time before re-entering. China successfully practiced this sort of high-speed return from lunar orbit in 2014 with its Chang’e 5-T1 dress-rehearsal mission.
China’s complex Chang’e 5 lunar sample return mission is set to launch between 20:00-21:00 UTC (3-4 pm ET (04-05:00 am local tomorrow). It will seek to return the first lunar samples since the 1970s. Thread on the launch, spacecraft, science and more. pic.twitter.com/bxRxAfSnme
— Andrew Jones (@AJ_FI) November 23, 2020
Mons Rümker and the nearby landing site was specifically chosen because it’s thought to represent one of the newer geological features, which formed late on the otherwise ancient and pockmarked face of the Moon. Mons Rümker is a large volcanic formation, 70 km across and rising 1,100 meters above the surrounding lunar plain. The feature is similar to shield volcanoes on Earth and is one of a very few large volcanic features on the Moon visible with a backyard telescope.
The lander is equipped with a spectrometer, ground-penetrating radar, thermo-detector, and rotary-percussive drill located on the lander’s scoop arm, along with instruments for initial analysis of the soil upon acquisition.
Researchers are hoping that the sample will contain an example of pristine basaltic lunar mare material. Like the Apollo sample returns and the soon-to-return asteroid samples courtesy of Japan’s Hayabusa 2 and NASA’s Osiris-REX, whatever Chang’e 5 brings back will become a legacy sample, available for analysis for years to come as new studies and methods become available.
This is only the latest from the Chang’e initiative, which takes its name from the Chinese Moon goddess. The Chang’e 3 lander and Yutu (“Jade Rabbit”) rover explored Mare Imbrium in 2013, the Queqiao relay orbiter arrived in 2018, and the Chang’e 4 mission made the first soft landing on the lunar farside in early 2019.
Chang’e 5 was delayed to late 2020 largely due to issues with the new Long March 5 heavy-lift rocket needed to send the mission to the Moon. The rocket carried out its successful inaugural flight in late 2016, then suffered a failure in mid-2017 that grounded the launch system until a successful return to flight in late 2019. The most recent Long March 5 launch on July 23, 2020, sent China’s first Mars mission Tianwen 1 towards the Red Planet, for an arrival in early 2021.
Next up, China plans to send a second Chang’e 6 sample return mission to the Moon in the 2024 time frame. After that, China has plans for a robotic research station at the lunar South Pole, perhaps followed by eventual crewed lunar landings.