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November 25th, 2020
Credit: Big Ear Radio Telescope
In search for extraterrestrial intelligence circles, the famous “Wow!” signal appears to be a still-standing indication of detecting other starfolk.
Reports Alberto Caballero, an amateur astronomer and one of the founders of The Exoplanets Channel: “As of October 2020, the WOW! Signal remains the strongest candidate SETI signal.”
The Wow! signal was a strong narrowband radio signal received on August 15, 1977 by Ohio State University’s Big Ear radio telescope.
Astronomer Jerry Ehman discovered the anomaly a few days later while reviewing the recorded data – writing on the computer printout “Wow!” He also circled the string 6EQUJ5 representing the signal’s intensity variation over time. The entire signal sequence lasted for the full 72-second window during which Big Ear was able to pick the signal up.
The Big Ear Observatory
Courtesy of North American Astrophysical Observatory
Candidate source
In Caballero’s paper – “An approximation to determine the source of the WOW! Signal” – he reports on his analysis of the thousands of stars in the WOW! Signal region that could have the highest chance of being the real source of the signal, providing that it came from a star system similar to ours.
A candidate source, Caballero surmises, is named 2MASS 19281982-2640123, “an ideal target to conduct observations in the search for potentially habitable exoplanets.”
In red, the two regions where the Wow! signal could have originated.
Source: Alberto Caballero/Pan-STARRS/DR1
Wanted: more information
However, Caballero points out that more information is needed in order to determine that 2MASS 19281982-2640123 is indeed a Sun-like star, he adds.
“Moreover, another 14 potential Sun-like stars in the WOW! Signal region were found in the Gaia Archive, but the estimations on their luminosity were unknown,” Caballero explains.
“In any case, since all these stars are located in the same part of the sky, it is ideal to search for exoplanets in the whole region where the WOW! Signal could have come from,” he concludes.
To read the Caballero paper — “An approximation to determine the source of the WOW! Signal” — go to:
https://arxiv.org/ftp/arxiv/papers/2011/2011.06090.pdf
Also, take a read of: “The Big Ear Wow! Signal – What We Know and Don’t Know About It After 20 Years,” written by Dr. Jerry R. Ehman (Last Revision: February 3, 1998)
Go to: http://www.bigear.org/wow20th.htm
Just for you “SETI whisperers” out there: In late 1997, after almost 40 years of operation, the Big Ear radio ceased operation. The telescope was destroyed in early 1998. An adjacent 9-hole golf course was expanded into 18 holes and about 400 homes were planned for construction on the nearby land owned by those developers.
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Curiosity Mast Camera Left photo taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech/MSSS
NASA’s Curiosity Mars rover is now carrying out Sol 2952 duties.
Curiosity Mast Camera Left image acquired on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech/MSSS
Curiosity Mast Camera Left image taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech/MSSS
Curiosity Mast Camera Left image taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech/MSSS
Curiosity Mast Camera Left image taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech/MSSS
Curiosity’s Location: Sol 2951. Distance Driven 14.59 miles (23.49 kilometers). Credit:
NASA/JPL-Caltech/Univ. of Arizona
Curiosity rolled up a particularly steep (roughly 20 degrees) slope. Image taken by rover’s Left Navigation Camera on Sol 2950 November 23, 2020
Credit: NASA/JPL-Caltech
NASA’s Curiosity Mars rover is now performing Sol 2952 tasks.
Curiosity Front Hazard Avoidance Camera Left B image acquired on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech
“Our weekend drive stopped a bit shorter than planned when Curiosity played it safe rolling up a particularly steep (~20 degrees) slope,” reports Michelle Minitti, a planetary geologist at Framework in Silver Spring, Maryland. But even with the rover parked at a tilt, we could still accomplish all our desired science at this stage of our drive back up Mount Sharp.”
Curiosity Right B Navigation Camera image taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech
Texture and chemistry
A recent plan calls for making another observation of rock texture and chemistry with the robot’s Mars Hand Lens Imager (MAHLI) and Alpha Particle X-Ray Spectrometer (APXS), respectively, of “Saughieside Hill,” part of the bedrock making up the arcuate benches the rover has been traversing over the last couple of weeks.
The Chemistry and Camera (ChemCam) will measure the chemistry of another nearby bedrock target, “Gathersnow Hill,” which sits at the edge of the lip that halted Curiosity’s drive, Minitti explains.
Mastcam is set to image the layered structure of Gathersnow Hill in stereo, and more broadly, will acquire mosaics that capture the structures of the bedrock both behind and ahead of the rover.
Curiosity Left B Navigation Camera image taken on Sol 2951, November 24, 2020.
Credit: NASA/JPL-Caltech
Minitti adds that ChemCam gets in on the imaging action, taking a small Remote Micro-Imager (RMI) mosaic of stratigraphic features in the target “Hamar.”
Drive ahead
“After a roughly 30 meters drive [98 feet], Curiosity will image the area around her with Navcam and Mastcam in preparation for activities over the upcoming American Thanksgiving long weekend,” Minitti says, “as well as the sky with a late day Mastcam image to measure the amount of dust in the atmosphere and a Navcam movie looking for clouds.”
“On Sol 2952, we will acquire an autonomously-targeted ChemCam analysis of the bedrock near the rover at our new post-drive location, a midday Navcam measurement of the amount of dust in the atmosphere, and a Navcam movie looking for clouds,” Minitti reports.
Curiosity Rear Hazard Avoidance Left B Camera image taken on Sol 2950, November 23, 2020.
Credit: NASA/JPL-Caltech
Monitoring extravaganza
On the final sol of the 2951-2953 plan, Mars researchers are slated to have an environmental monitoring extravaganza with a ChemCam passive observation of the sky, Navcam and Mastcam measurements of the amount of dust in the atmosphere, Navcam images and movies to look for dust devils, and an APXS measurement of atmospheric argon,” Minitti adds.
Dynamic Albedo of Neutrons (DAN), Radiation Assessment Detector (RAD), and Rover Environmental Monitoring Station (REMS) measurements run regularly across the three sols of the plan.
“All told, Curiosity will stay as busy as a shopper hitting those early Black Friday deals,” Minitti concludes.
Credit: CAST
China’s Chang’e-5 Moon mission faces a complex set of step-by-step stages to collect and return lunar samples back to Earth.
The craft’s departure atop a Long March-5 Y5 booster from the Wenchang Spacecraft Launch Site occurred at 4:30 a.m. Beijing time.
Credit: CCTV/Inside Outer Space Screengrab
Weighing 8.2 tons, Chang’e-5 consists of an orbiter, a lander, an ascender and a returner.
On track
“According to the report of the aerospace control center, the Long March-5 rocket was in normal flight and the Chang’e-5 spacecraft has accurately entered the preset orbit,” said Zhang Xueyu, director of southwest China’s Xichang Satellite Launch Center and chief director of the Chang’e-5 mission.
Credit: ESA
Chinese Tianlian relay satellites were utilized in the launch of Chang’e-5.
Meanwhile, two space tracking ships from China’s Yuanwang fleet — Yuanwang-5 and Yuanwang-6 — completed their maritime monitoring of the Chang’e-5 probe launch in the Pacific Ocean on Tuesday morning. The maritime monitoring process lasted a total of 1,100 seconds. The two ships sent accurate real-time data to spacecraft control centers in Beijing and Wenchang, according to China’s Xinhua news agency.
Credit: New China TV/Inside Outer Space screengrab
The European Space Agency (ESA) is supporting the mission by tracking the spacecraft during two of the mission’s most critical phases and is providing on-call back-up for China’s own ground stations.
Credit: New China TV/Inside Outer Space screengrab
Next stages
“The next ten stages of Chang’e-5 mission include key orbital corrections, capture of the spacecraft when it reaches the Moon’s orbit, the separation of the orbiter, lander, ascender and returner of Chang’e-5, touching down the Moon’s surface, lunar sampling, lunar surface takeoff, lunar orbit rendezvous and docking, transfer of samples, departing from the Moon’s orbit, returning to Earth and reentering the Earth’s atmosphere,” Xie Jianfeng, chief engineer of the Chang’e-5 mission, told China Central Television (CCTV).
Ascender departs Moon with samples. Credit: New China TV/Inside Outer Space screengrab
Docking of ascender with orbiter-returner. Credit: New China TV/Inside Outer Space screengrab
The lander-ascender is targeted to touch down on the northwest region of Oceanus Procellarum — also known as the Ocean of Storms — on the near side of the Moon in early December.
Rocks and regolith
Following touchdown, within 48 hours, a robotic arm is to scoop up rocks and regolith on the lunar surface. Also a drill will bore into the ground. About 4.4 pounds (2 kilograms) of samples are expected to be collected and sealed in a container in the spacecraft.
Lunar samples head for Earth landing. Credit: New China TV/Inside Outer Space screengrab
With its lunar collectibles onboard, the ascender will take off, and dock with the orbiter-returner in orbit. Following transfer of the samples to the returner, the ascender will separate from the orbiter-returner.
Around December 15 the returner will reenter the Earth’s atmosphere using a skip maneuver, then land under parachute at the Siziwang Banner in north China’s Inner Mongolia Autonomous Region.
Skip reentry. Credit: New China TV/Inside Outer Space screengrab
The entire flight will last more than 20 days.
Only two other countries, the United States via the Apollo program, and the former Soviet Union’s robotic Luna program, have brought samples back from the Moon. If everything goes well, Chang’e-5 would be the first robotic lunar sample return mission since Luna 24 in 1976.
Credit: New China TV/Inside Outer Space screengrab
Milestone mission
“The Chang’e-5 lunar mission is China’s first attempt to retrieve planetary soil sample from an extraterrestrial body and return to Earth. There are many firsts,” said Zhao Huanzhou, deputy chief engineer of Chang’e-5 lunar mission at Beijing Aerospace Flight Control Center in an interview with CCTV. “This mission features the most intensive and demanding control tasks, the most emergency branches and the most fault modes in China’s aerospace history,” Zhao said.
Credit: New China TV/Inside Outer Space screengrab
“We could call it a milestone mission,” said Peng Jing, deputy chief designer of the Chang’e-5 probe from the China Academy of Space Technology under the China Aerospace Science and Technology Corporation. “Its success will help us acquire the basic capabilities for future deep space exploration such as sampling and takeoff from Mars, asteroids and other celestial bodies,” Peng said.
New China TV has released a video detailing the various aspects of the Chang’e-5 lunar sample mission.
Go to:
CCTV Video News Agency has issued this video regarding the Chang’e-5 mission. Go to:
https://www.youtube.com/watch?v=b9J64y3j54o
Credit: CAST
Given success of China’s Chang’e-5 mission to haul back to Earth lunar specimens, the Chinese National Space Administration (CNSA) is establishing procedures to share the material with international colleagues.
Lin Yangting, professor with the Institute of Geology and Geophysics of Chinese Academy of Science, told China Global Television Network that researchers need to hand in proposals for studying the samples beforehand, and follow a series of procedures prescribed by the CNSA.
“Now the procedure is still being discussed, it has not been fixed,” Lin said. “The procedure will be announced on the website of the CNSA…so we will apply for it. We will submit our application with a research proposal. There will be a committee to screen your application and then make the decision if you will get the samples or not.”
China’s Chang’e-5 lunar mission will attempt to haul back to Earth samples of the Moon.
Credit: CNSA/CLEP
ESA exchanges
Liu said that lunar-sample-related exchanges between Chinese scientists and their counterparts from the European Space Agency (ESA) have already begun, and further joint efforts can be realized within a new mechanism.
Roughly three years ago, the CNSA contacted ESA to discuss cooperation between European scientists and Chinese scientists working on lunar samples. “So we have discussed about this many times. And we are going to establish a joint scientist team, and this team will have several working groups. So we will work together on the new lunar samples,” Liu said.
New China TV has released a video detailing the various aspects of the Chang’e-5 lunar sample mission. Go to:
Credit: CAST
(Washington, DC) Today, House Science, Space, and Technology Committee Ranking Member Frank Lucas emphasized the risk the Chinese Communist Party (CCP) poses to American international leadership in science and technology following the launch of the CCP’s Chang’e-5 mission to the Moon.
“The launch of Chang’e-5 is a significant step by China towards their goal of establishing a long-term presence on the Moon. The nation that leads in space will dictate the rules of the road for future technological development and exploration, and the influence of the People’s Liberation Army (PLA) in the CCP’s space program makes China a particularly irresponsible and dangerous candidate. Advancements by the CCP also jeopardize American international competitiveness in science and technology. We can no longer take America’s leadership in space for granted and must continue supporting the men and women of the American space program aspiring to launch crewed missions to the Moon, Mars, and beyond.”
The China Task Force Report, an actionable plan to respond to the Chinese Communist Party’s growing influence, discusses China’s plans for space exploration and recommends that the U.S. ensure its leadership in the commercial space sector and maintain its commitment to human exploration of space: “While the U.S. views space exploration as a way to expand human knowledge, create new technologies, and discover new phenomena, the CCP seeks to establish leadership in space for the purpose of keeping the CCP in power and as a show of economic and national security strength,” the Report reads. “Unlike the U.S., which has a civilian agency (NASA) overseeing space exploration, the PLA manages the People’s Republic of China’s (PRC) space program. The CCP dedicates high-level attention and funding for space while also aggressively attempting to acquire U.S. space startup companies and technology, both through legitimate means and coercion and theft.
“If the PRC succeeds in its efforts to launch its first long-term space station module in 2022, it will have matched the U.S.’ nearly 40-year progression from first human spaceflight to first space station module in less than 20 years,” the report continues. The CCP is vocal about plans to establish a human base on the Moon. The U.S. should be concerned about the technological innovations and leadership role for the CCP that could come from missions crewed by PRC-nationals to the Moon.”
The image above, peeking over the deck of Curiosity with Navcam, gives an impression of the laminated outcrops along the way. Photo taken by Left Navigation Camera onboard NASA’s Mars rover Curiosity on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech
NASA’s Curiosity Mars rover is now performing Sol 2949 tasks.
Curiosity Front Hazard Avoidance Camera Right B image taken on Sol 2949, November 22, 2020.
Credit: NASA/JPL-Caltech
“While it doesn’t rain in Gale crater, Curiosity is quite familiar with wind, and she watches out for the atmospheric phenomena around herself,” reports Susanne Schwenzer, a planetary geologist at The Open University; Milton Keynes, U.K.
“As we are again in the dust storm season, Curiosity monitors the environment even more closely,” Schwenzer notes. A current plan includes a Navcam line of sight imaging activity and Mastcam basic tau – both to watch the opacity in the atmosphere.
Two images from the Mast Camera (Mastcam) on NASA’s Curiosity rover depicting the change in the color of light illuminating the Martian surface since a dust storm engulfed Gale Crater. The left image shows the “Duluth” drill site on Sol 2058 (May 21, 2018); the right image is from Sol 2084 (June 17, 2018).
Credit: NASA/JPL-Caltech/MSSS
“Those are not from the typical cadence of activities Curiosity performs outside the dust storm season but are added especially now due to the potential for increased regional dust activity,” Schwenzer adds. “Curiosity also watches out for dust devils again in this plan. So, while it doesn’t rain at Gale crater, there is still a lot to watch out for!”
Curiosity Left B Navigation Camera image acquired on Sol 2949, November 22, 2020.
Credit: NASA/JPL-Caltech
Portfolio of bedrock targets
On the rocky side, Curiosity will perform an Alpha Particle X-Ray Spectrometer (APXS) measurement on the target ‘Giova,’ which is a bedrock target.
Curiosity Mast Camera Left image taken on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech/MSSS
The robot’s Chemistry and Camera (ChemCam) will look at the same target and add to its portfolio of bedrock targets by investigating the targets ‘Green Blett’ and ‘Gribun.’
“The team decided to focus on the bedrock because we are on the move again, and we are expecting to see changes in the bedrock chemistry as we travel along the landscape,” Schwenzer reports.
On the road again
With so much to look at, Mastcam is really busy in a current plan, imaging several of those outcrops, and taking a larger workspace image, too, Schwenzer says.
Curiosity Mast Camera Left image taken on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech/MSSS
“On top of it all, and to the delight of the mineralogists like me, there also is a multispectral image of the target Giova – to be taken after the [Dust Removal Tool] DRT and APXS activity,” Schwenzer notes. “After so much atmospheric science, geochemistry and imaging for sedimentology, Curiosity gets on the road again, rolling along those beautiful benches and outcrops that have so much to tell about the geologic and geochemical history of Gale crater!”
Curiosity’s Location as of Sol 2943. Distance Driven 14.52 miles (23.37 kilometers).
Credit: NASA/JPL-Caltech/Univ. of Arizona
Long March-5 at the launch pad. Chinese Lunar Exploration Program (CLEP) insignia: a lunar crescent with two footprints at its center. The symbol resembles the Chinese character for “Moon.”
Credit: CCTV/Inside Outer Space screengrab
China is marching forward on the launch next week of the Chang’e-5 lunar mission – a complicated undertaking to haul back to Earth samples of the Moon.
Chang’e-5 spacecraft being readied for its lunar sample return mission.
Credit: CCTV via Andrew Jones screengrab
In preparation, south China’s Wenchang Space Launch Center rolled out to the launch pad the lunar probe’s carrier rocket, the Long March-5.
China space tracking ship sails for Chang’e-5 mission
Credit: China state-affiliated media
China’s second-generation space tracking ship, Yuanwang-3, departed on November 19 to support the Chang’e-5 mission.
Four-part spacecraft
The Chang’e-5 spacecraft weighs over eight tons and is comprised of four parts: an orbiter, a returner, an ascender and a lander.
China’s Chang’e-5 lunar mission will attempt to haul back to Earth samples of the Moon.
Credit: CNSA/CLEP
The lander will collect the lunar samples, place those collectibles in a vessel aboard the ascender, which will dock with the orbiter and returner that is circling the moon. The samples will then be transferred to the returner. After separation, the returner re-enters the Earth’s atmosphere, expected to parachute into north China’s Inner Mongolia in mid-December.
Practice session for upcoming launch of Chang’e-5 mission.
Credit: CCTV-Plus/Inside Outer Space screengrab
The robotic mission goal is to land on the Moon then haul back to Earth some 4 pounds (2 kilograms) of lunar regolith, possibly from as deep as 6.5 feet (2 meters) below the lunar surface.
If the mission is successful, China will become the third country in the world that is capable of bringing back samples from the Moon – after the United States and the former Soviet Union.
Chang’e-5 is the first robotic lunar sample return mission since the Soviet Union Luna 24 mission returned samples from Mare Crisium in 1976, 44 years ago.
Simulation of Long March-5 launch has been carried out by a network of centers.
Credit: CCTV-Plus/Inside Outer Space screengrab
Joint exercise
Meanwhile, a lunar exploration mission joint exercise before a projected November 24 launch has been carried out.
Technicians practice for next week’s launch of the Chang’e-5 mission.
Credit: CCTV-Plus/Inside Outer Space screengrab
The exercise to debug and practice control tasks involved the Beijing Flight Control Center, the Wenchang Space Launch Site, Xi’an Satellite Measurement and Control Center, and the Yuanwang Survey Fleet. During this joint exercise, the flight control center simultaneously inspected the execution of multiple tasks.
Go to this CCTV-Plus video (in Chinese):
http://pv.news.cctvplus.com/2020/1121/8166522_Preview_1615.mp4
Curiosity Right B Navigation Camera image taken on Sol 2946, November 19, 2020.
Credit: NASA/JPL-Caltech
NASA’s Curiosity Mars rover is now performing Sol 2948 tasks.
Curiosity Right B Navigation Camera photo acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech
“We are continuing our ‘benches’ mini-campaign and the current bench is spread out before us like a brick road on our way to our next stop,” reports Scott Guzewich, an atmospheric scientist at NASA’s Goddard Space Flight Center.
Curiosity Left B Navigation Camera photo acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech
Curiosity is continuing to study these erosion-resistant rock layers as the robot drives steadily toward the sulfate unit of Mt. Sharp.
Distant terrains
A recent plan passed on an opportunity for additional contact science and instead chose a variety of remote sensing with the rover’s Chemistry and Camera (ChemCam) and Mastcam.
Curiosity Chemistry & Camera Remote Micro-Imager (RMI) photo acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech/LANL
Laser shots as viewed by Curiosity Chemistry & Camera Remote Micro-Imager (RMI), acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech/LANL
Outside of two nearby targets for ChemCam Laser Induced Breakdown Spectroscopy (LIBS), ChemCam was looking forward to the sulfate unit with a long-distance image. “In this way,” Guzewich notes, “ChemCam almost works like the rover’s binoculars to see detail in distant terrains!”
Charged up
Also in the plans, a long dust devil movie and cloud monitoring activities.
“To best maintain the rover’s battery, we like to maintain a medium-to-high level of charge, but not too close to 100% charged,” Guzewich adds. “In fact, on occasion, we keep the rover awake so the battery doesn’t get too close to fully charged.”
A new science activity is included in the rover’s plan whenever this is needed.
“It’s a combination of our cloud and dust devil movies and today we’ll include it in the evening of Sol 2948 to look for both of these atmospheric processes,” Guzewich concludes.
Curiosity Left B Navigation Camera photo acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech
Curiosity Left B Navigation Camera photo acquired on Sol 2947, November 20, 2020.
Credit: NASA/JPL-Caltech
Curiosity’s Location as of Sol 2943, Distance Driven 14.52 miles (23.37 kilometers)
Credit: NASA/JPL-Caltech/Univ. of Arizona
Credit: SOM
As part of the European Space Agency’s Moon Village initiative, a lunar community study has been carried out by architecture, interior design, engineering and urban planning firm Skidmore, Owings & Merrill (SOM).
The detailed village design was done in collaboration with ESA and the Department of Aeronautics and Astronautics of the Massachusetts Institute of Technology (MIT).
Their proposal has undergone rigorous examination by ESA experts at the Agency’s mission-evaluating Concurrent Design Facility (CDF).
Multiple habitats making up Moon Village.
Credit: SOM
No show-stoppers
This review process flagged various issues but found no show-stoppers – perhaps an important step for establishing such domiciles on the Moon in years to come.
“This study is clearly looking into the future, beyond the horizon of currently planned lunar exploration activities,” explains Advenit Makaya, study leader at ESA. “But it has been a very interesting exercise for the various ESA experts, to collaborate with architecture experts, to identify and address the drivers and ways in which this innovative design could be deployed on the Moon.”
Architectural firm Skidmore, Owings & Merrill has designed a semi-inflatable four-level Moon Village habitat. The four-person crew quarters would be on the ground floor to maximize radiation protection.
Credit: SOM
Inflatables
As a starting point, SOM took the Bigelow Aerospace inflatable BEAM module currently attached to the International Space Station. SOM designed a semi-inflatable shell structure to offer the highest possible volume to mass ratio. Once the semi-inflatable structure inflated on the lunar surface, it would reach approximately double its original internal volume.
Ground floor crew quarters.
Credit: SOM
Shackleton crater site
The chosen site: the rim of Shackleton crater at the lunar South Pole. Avoiding the crippling temperature extremes of the Moon’s two-week days and nights, this location offers near-continuous sunlight for solar power, an ongoing view of Earth and access to potential lunar water ice deposits in adjacent permanently-shadowed craters.
Shackleton Crater, the floor of which is permanently shadowed from the Sun, appears to be home to deposits of water ice. A new study sheds light on how old these and other deposits on the Moon’s south pole might be.
Credit: NASA/GSFC/Arizona State University
Once the first habitat is in place, the SOM team envisages additional modules joining it in turn, customized for specific functions such as research, manufacturing, food culture and tourism – allowing the base to expand into a village, then eventually a city.
Take a look at the full Concurrent Design Facility (CDF) study here at:
http://esamultimedia.esa.int/docs/cdf/Moon_Village_v1.1_Public.pdf
