Luna 2076 – Page 4 – The Geopolitics of Lunar Colonization

Satellite Constellations, the Kessler Effect, and Military Superiority

November 6, 2020

A satellite constellation — DARPA illustration

As the United States military machine becomes increasingly dependent upon constellations of satellites for its command, control and communications, potential adversaries such as China and Russia have become experimenting with methods to destroy or disable the satellites. Now U.S. strategists are sounding the alarm about anti-satellite weapons, or ASATs, reports GeekWire.

“We built [the command and control satellites] as if we were in a benign domain.” said Lt. Gen. John Shaw, commander of the U.S. Space Force’s Space Operations Command. But it’s becoming increasingly clear that space is becoming “a contested domain.”

Adding complexity to the strategic thinking about space is a potential phenomenon sometimes referred to as the Kessler syndrome. Donald J. Kessler wrote in 1979 how the density of objects in Low EarthOrbit could get high enough that collisions between objects could cause a cascade — creating debris that struck other objects, thus creating more debris. The movie “Gravity” was based on a scenario in which the Russians shot down a defunct satellite, creating a cloud of debris moving at 20,000 to 50,000 miles per hour. Apparently, military thinkers give such a scenario credence. more “Satellite Constellations, the Kessler Effect, and Military Superiority”

Coming Soon: the Cislunar Highway Patrol System

November 5, 2020

An important duty assumed by the embryonic U.S. Space Force will be tracking objects in cislunar space (the area between the Earth and Moon). The Air Force Research Laboratory’s Space Vehicles Directorate is now investigating technologies to undertake the task, reports Space News.

“It’s a brave new world for the [Department of Defense] to embark on,” said Capt. David Buehler, manager of the AFRL experiment named CHPS, for Cislunar Highway Patrol System. Said he:

“If we’re going to protect and defend, the Space Force is going to need to understand the environment, have space domain awareness capabilities to be able to know where everything is out there.”

Tracking objects in cislunar space presents significant technical challenges. One is estimating the trajectory objects that are subject to the gravity of both Earth and the Moon. Said Buehler: “As you go further and further beyond GEO, you start to have these weird, non-closed trajectories, they no longer look like orbits, they’re more open-ended trajectories.”

The distances are vaster than tracking objects in Earth orbit, and the brightness of the Moon creates problems for sensors. more “Coming Soon: the Cislunar Highway Patrol System”

Challenges of Building a Lunar Telecommunications Infrastructure

November 2, 2020

Building a wireless communications infrastructure on the Moon will face challenges not found on Earth, but the end result could be superior communications.

In addition to power and shelter, a lunar base station will need a way to communicate with Earth, with astronauts outside the habitat, and with lunar rovers. Anticipating that need, NASA has awarded Nokia Bell Labs and 13 other companies, including SpaceX and Lockheed-Martin, five-year contracts totaling more than $370 million to demonstrate key infrastructure technologies on the lunar surface, reports IEEE Spectrum.

The antennas and base stations will need to be ruggedized for the harsh, radiation-intensive environment, plus a lunar day-light cycle in which temperatures swing more than 250ºC between light and shadow. Because every piece of hardware in the network must be transported from Earth, equipment needs to be hardened for stresses such as vibration, shock and acceleration from launch and landing.

Designers also want to avoid polluting the lunar surface with radio signals that might interfere with radio astronomy. Radio Frequency Interference (RFI) “can be mitigated at the source with appropriate shielding and precision in the emission of signals,” writes Emma Alexander, a physicist writing for The Conversation. “Astronomers are constantly developing strategies to cut RFI from their data. But this increasingly relies on the goodwill of private companies.”

The good news is that the lack of an atmosphere and absence of terrestrial obstructions such as trees and buildings likely will mean better signal propagation.

Moon May Contain Billions of Tons of Buried Ice

October 26, 2020

Left: Cumulative ejecta deposited outside of craters. Right: Ejecta deposited inside these craters after they formed.

Scientists who have modeled 4 billion years of the Moon’s meteor-impact history have concluded that the Moon holds more water than previously believed. Much of it is buried, as much as 10 meters deep.

“We looked at the entire time history of ice deposition on the Moon,” said Keven Cannon, a planetary scientist at the Colorado School of Mines and lead author of the study in Geophysical Research Letters. “If the coldest regions have been stable and accumulating ice for billions of years, then some could have very substantial deposits, but they might be buried up to 10 meters deep or more.” more “Moon May Contain Billions of Tons of Buried Ice”

Molecular Water Found in Clavius Crater

October 26, 2020

The Stratospheric Observatory for Infrared Astronomy (SOFIA) has detected evidence of molecular water in the regolith of Clavius Crater, a large crater visible from Earth in the Moon’s southern hemisphere. The airborne SOFIA observatory, a partnership between NASA and the German Aerospace Center, flies in a modified Boeing 747SP aircraft above the atmospheric water that blocks ground observation.

Satellites have had detected “hydrates” in the lunar regolith but could not distinguish between OH (hydroxyl) and H20 (molecular water). SOFIA was able to measure the precise being vibration of the H-O-H molecular bond at 6.1 µm in the infrared.

SOFIA targeted high lunar latitudes near the South Pole where low temperatures could allow migrating water to transiently remain on the surface and high hydroxyl abundances could create and trap water when impacted by small meteorites. Although Clavius has a relatively high concentration of water by lunar standards, says NASA, it is roughly one-hundredth of the water found in the Sahara desert. more “Molecular Water Found in Clavius Crater”

Yes, Plants Can Grow in Lunar Regolith, But Not All Thrive

October 22, 2020

plants growing in lunar and Martian soil simulants. Photo credit: Wamelink et al, Open Agriculture, 2019.

Long-term colonization of the Moon will require settlers to grow much of their own food, and they won’t have any soil rich in organic matter to start with. Hydroponics is one alternative. Growing plans in mineral-rich lunar regolith is another.

Dutch researchers with Wageningen University & Research have been testing a variety of vegetables to see how well they fare in regolith — tomatoes, rye, watercress, leeks, quinoa, peas, radish, spinach, arugula and chives.

The researchers couldn’t use real lunar regolith, but they created a substitute with similar chemical composition from volcanic ash near Flagstaff, Arizona. (To simulate Martian material, they found ash from Hawaii.) Regolith has only a small amount of reactive nitrogen, a critical element for life, and it can store only 30% as much water as organic Earth soil can.

The researchers set up trays containing the lunar regolith, Martian regolith and Earth soil, watered them each day, and studied the results over five months. Their findings, according to Smithsonian magazine:

Radishes, cress and rye could be harvested and produce seeds.
Tomatoes and peas could be harvested.
Chives and leeks grew slower than normal.
Quinoa produced flowers but no seeds.

more “Yes, Plants Can Grow in Lunar Regolith, But Not All Thrive”

LunaNet: An Internet for the Moon

October 20, 2020

Artist’s conception of LunaNet being used by astronauts Credit: NASA/Reese Patillo

NASA has issued a Request for Information to help it flresh out plans for LunaNet, a communications and navigation architecture for the Moon.

While communications at present are limited to portions of the Moon facing the Earth, LunaNet would allow robotic landers, rovers, scientific devices and astronauts to transit data to Earth through Moon-orbiting satellites or space stations from the far side or poles of the Moon.

According to GCN, LunaNet is expected to include three categories of services:

Networking services capable of moving data between nodes that adhere to confidentiality, integrity and availability requirements.
Position, navigation and timing services for orientation and velocity determination, as well as time synchronization and dissemination. These services could be used for search and rescue, surface navigation and location tracking
Science services providing situational alerts and scientific measurements that could support predictions of major solar eruptions that affect space weather.

China Plans Next Two Chang’e Missions

October 19, 2020

After the success of its Chang’e 4 lander on the far side of the Moon, China has laid out an ambitious roadmap for continued lunar exploration. Chang’e 6 is scheduled to head to the Moon in 2023 or 2024, and Chang’e 7 in 2024 with the aim of landing at the south pole.

Chang’e 7 will have multiple components, including an orbiter, a relay satellite, a lander, a rover, and a mini-flying craft. Scientific payloads will study volatile compounds and isotopes, and measure heat flow through the lunar soil, reports Space.com. The flying craft will carry instrumentation to measure water molecules in permanently shadowed areas.

Chang’e 8, scheduled for the late 2020s, also will focus on the south pole. That mission will test technology for using local resources and 3D-printing manufacturing.

Earth, Moon Shared Magnetosphere 4 Billion Years Ago

October 15, 2020

Earth’s magnetosphere. Credit: Futurismic.com

The Earth and Moon shared the same magnetic field some 3.5 billion to 4.1 billion years ago, and the Moon’s field helped shield the Earth from solar radiation that might have stripped away its atmosphere, concludes a NASA-led study published in the journal Science Advances.

“The Moon seems to have presented a substantial protective barrier against the solar wind for the Earth, which was critical to Earth’s ability to maintain its atmosphere during this time,” said Jim Green, NASA’s chief scientist and lead author of the study, as reported by Business Insider India.

The scientists created a computer model to simulate the behavior of the magnetic fields of the two orbs. The magnetospheres of the Moon and Earth would have been magnetically connected in the polar regions of each body. At certain times, the Moon’s magnetosphere would have served as a barrier to harsh solar radiation bombarding the Earth-Moon system.

The model also suggests that there was some atmospheric exchange as well. The Sun’s radiation would have charged neutral particles in the Earth’s upper atmosphere, enabling them to travel to the Moon along the lunar magnetic lines. The process might have contributed to the Moon maintaining a thin atmosphere, including nitrogen.

As the Moon cooled and lost its magnetosphere, solar wind stripped the atmosphere away.

Moon as Best Location for SETI Telescope

October 12, 2020

Radio image of the night sky. Credit: MPIA/Glyn Haslam

The far side of the Moon is one of the most radio-quiet locations in the Earth-Moon system, which makes it an favorable spot for the Search for Extraterrestrial Intelligence (SETI), which scans the skies for radio communications.

Radio telescopes on Earth are located in isolated parts of the globe with minimal radio pollution, but they can’t compare to the far side of the Moon for blocking out radio interference. The idea is not a new one, but it has gotten fresh life thanks to a white paper submitted to the National Academy of Sciences’ Planetary Science and Astrobiology Decadal Survey 2023-2032. The team is led by Eric J. Michaud, a mathematics undergraduate at UC Berkeley, reports Phys.org.

The need to establish a site for a radio telescope is pressing, says Dr. Pete Worden, former director of NASA’s Ames Research Center. “There is some urgency in establishing a lunar far-side radio-quiet reserve before we get the burgeoning problem we have in Earth orbit with optical interference from communications satellites. We are already concerned about the Chinese communications satellites—so this needs to be a global consensus now!”

Radio noise could be mitigated all the more if the telescope were located in a crater. Crater walls would block out interference from orbiters or spacecraft that will become increasingly common on the Moon.

A lunar location would have two big drawbacks: One would be the cost of delivering the telescope to the far side of the Moon. Another, assuming the main energy source was solar, would be the difficulty of storing enough energy to last a two-week lunar night.

An alternative to a ground facility would be a telescope deployed in lunar orbit. One bonus: the weightlessness of orbit would do away with the need for a supporting structure. But the nature of the Moon’s gravitational field means that most lunar orbits are inherently unstable, which creates a new set of problems.

As Michaud concedes, much work needs to be done before the dream of a lunar SETI observatory can be realized.

Bacon’s bottom line: If the technical hurdles can be addressed, a SETI mission could add impetus to building a lunar transportation and logistical infrastructure and possibly a justification for maintaining a scientific staff on the Moon. Scientific investigation will lead the way in early lunar development.