New studies struggle to explain the origin of the Moon

The uncertainty of science: Three new studies on the mystery of the origin of the Moon all appear to better confirm the theory that it was created when the Earth collided with a Mars-sized planet.

It is important to be aware of the uncertainties here. All these studies were done to try to address problems with the impact theory, and though they kind of answer the questions, they leave behind some important doubts.

Did the Moon’s axis shift 3.5 billion years ago?

The uncertainty of science: Because the concentrations of ice on the moon are thought to be located on opposite sides of the planet, both locations 5.5 degrees away from the poles, a team of scientists has proposed that these locations were once the Moon’s poles and that the axis got shifted 3.5 billion years ago when a gigantic volcanic hotspot on the surface erupted.

He and his colleagues assumed that when the ice was deposited, it was centered on the poles. But what kind of event could have moved the poles by 5.5°? Known asteroid impacts were too small or in the wrong location to do the job. Instead, the team hypothesizes that a 3.5-billion-year-old hot spot could have nudged the poles to their present-day position. Pouring out enormous amounts of lava, that hot spot created Oceanus Procellarum, the vast dark spot on the near side of the moon. The Procellarum region is known to have high concentrations of radioactive elements that would have been hot in ancient times. The research team theorizes that this heat would have created a less dense lens in the moon’s mantle that would have caused the axis to wobble into today’s position.

This theory requires that the Moon’s ice is at least this old, which is quite a stretch. Also, if the Procellarum eruption caused a pole shift, I wonder why the other large lunar eruptions, which created the Moon’s other mare, did not shift the poles further and in other directions.

Giant lava tubes possible on the Moon

New analysis of the lunar geology combined with gravity data from GRAIL now suggests that the Moon could harbor lava tubes several miles wide.

David Blair, a graduate student in Purdue’s Department of Earth, Atmospheric and Planetary Sciences, led the study that examined whether empty lava tubes more than 1 kilometer wide could remain structurally stable on the moon. “We found that if lunar lava tubes existed with a strong arched shape like those on Earth, they would be stable at sizes up to 5,000 meters, or several miles wide, on the moon,” Blair said. “This wouldn’t be possible on Earth, but gravity is much lower on the moon and lunar rock doesn’t have to withstand the same weathering and erosion. In theory, huge lava tubes – big enough to easily house a city – could be structurally sound on the moon.”

You can read their paper here. If this is so, then the possibility of huge colonies on the Moon increases significantly, as it will be much easier to build these colonies inside these giant lava tubes.

An iron rain fell on Earth early in its formation

New research attempting to explain why the Earth but not the Moon has so much iron splattered through its mantle has found that iron can be more easily vaporized during impacts than previously thought, and thus rained down on the planet during the early asteroid bombardment.

Principal investigator Kraus said, “Because planetary scientists always thought it was difficult to vaporize iron, they never thought of vaporization as an important process during the formation of the Earth and its core. But with our experiments, we showed that it’s very easy to impact-vaporize iron.” He continued, “This changes the way we think of planet formation, in that instead of core formation occurring by iron sinking down to the growing Earth’s core in large blobs (technically called diapirs), that iron was vaporized, spread out in a plume over the surface of the Earth and rained out as small droplets. The small iron droplets mixed easily with the mantle, which changes our interpretation of the geochemical data we use to date the timing of Earth’s core formation.”

The Moon’s gravity in turn wasn’t sufficient to pull its own iron vapor down. Thus, it does not have much iron in its mantle.

Yutu reveals a complex lunar geology

The uncertainty of science: The Chinese lunar rover Yutu has uncovered a much more complicated geology history than previously predicted at its landing site on the moon.

Those data paint a detailed portrait of the Chang’e 3 landing site, which sits just 165 feet (50 m) away from a 1,475-foot-wide (450 m) crater known as C1. C1 was gouged out by a cosmic impact that occurred sometime between 80 million and 27 million years ago, the study authors said.

Yutu studied the ground it rolled over, characterized the craters it cruised past and investigated an oddly coarse-textured rock dubbed Loong, which measures about 13 feet long by 5 feet high (4 by 1.5 m). Overall, the rover’s observations suggest that the composition of its landing site is quite different from that of the places visited by NASA’s Apollo missions and the Soviet Union’s Luna program.

The rover found 9 distinct layers, suggesting numerous and different past events that layered the surface.

Yutu lives!

Despite an engineering failure that has prevented it from roving after only a few days on the Moon, the Chinese lunar rover Yutu continues to reawaken after each long lunar night, surviving now far longer than its planned three month lifespan.

Since the rover arrived in late 2013, it has now functioned in the hostile lunar environment for more than a year. This, along with other successful long missions, suggests that Chinese space engineering has matured to a point that it has the ability to achieve some significant long term goals.

Earth’s other moon

Link here.

What you might not know is that the moon is not the Earth’s only natural satellite. As recently as 1997, we discovered that another body, 3753 Cruithne, is what’s called a quasi-orbital satellite of Earth. This simply means that Cruithne doesn’t loop around the Earth in a nice ellipse in the same way as the moon, or indeed the artificial satellites we loft into orbit. Instead, Cruithne scuttles around the inner solar system in what’s called a “horseshoe” orbit.

X-Prize contestants team-up to create head-to-head lunar race

The competition heats up: Two Google Lunar X-Prize contestants have teamed up to use the same rocket to get to the Moon together, where they will literally race head to head to see who travels the 500 meter distance first to win the prize.

At a press conference in Tokyo on Monday, the leaders of two Lunar X PRIZE teams—Astrobotic and HAKUTO—announced a plan in which the two teams’ robotic rovers will travel to the moon together and touch down on the lunar surface at the same time. They will then race each other to cover the 500 meters required to win the first place prize of $20 million.

John Thornton, head of Pittsburgh-based Astrobotic (a Carnegie Mellon University spin-off), said in a call with reporters that the partnership with HAKUTO (a spin-off from Tokyo University) represented the first step in realizing his team’s goal of turning robotic moon missions into a viable business. That mission won’t stop with this single partnership. He said the team was in talks with more than half of the other 16 GLXP competitors to carry their rovers to the moon, too, in exchange for sharing the cost of getting there and splitting prize money.

If this happens as they propose, we could be watching as many as ten rovers line up for the race.

South Korea unveils its own lunar rover

The competition heats up: South Korea has revealed its preliminary design for a lunar rover, set to launch in 2020 on a Korean-built rocket.

The article does not indicate whether this project has actually been approved or is merely being touted by Korea Institute of Science and Technology, which made the announcement. The cost to build it is estimated to be more than $7 billion, which seems quite exorbitant and over-priced.

Update: I had misread the conversion in the article from U.S. to Korean currency and thought the proposed cost for this mission was way more than it really is, which is about $7 million, a much more reasonable number. Thanks to Edward for the correction.

Private company offers to fly packages to Moon

Fly me to the moon! A company building a small lunar rover as part of the Google Lunar X-prize competition is now offering, for a small fee, to include private packages with its lander.

Astrobotic Technology on Thursday (Dec. 11) announced the launch of its new “MoonMail” program, which offers to send heirloom rings, family photos, locks of hair and other small personal items on the company’s first private moon mission set to launch in the next few years. With prices based on the item’s size, MoonMail rates start at $460 for a half-inch wide by 0.125-inch tall (1.27 by 0.3 centimeter) capsule and increase to $25,800 for a one by two-inch (2.54 by 5.08 cm) payload. “You can think of the pricing for it to be very similar to ‘it fits, it ships’ at the post office,” John Thornton, Astrobotic CEO, told collectSPACE.com in a call with reporters. “It is essentially a flat-rate box.”

They hope to launch on a Falcon 9. More interestingly, they want to land and explore one of the Moon’s skylight caves.

The first Griffin is slated to launch on a SpaceX Falcon 9 rocket and land at Lacus Mortis, or the “Lake of Death,” a plain of basaltic lava flows in the northeastern part of the moon as viewed from Earth. “There is a unique feature there called a ‘skylight,'” stated Thornton, adding that only about 300 of these sinkhole-like entrances into subsurface caves have been discovered on the moon. “What’s very unique about the skylight at Lacus Mortis is that its walls have collapsed creating a ramp into the cave. … Caves on the surface of the moon could be our natural shelter,” Thornton explained. “So our first mission goes to one of these caves where we hopefully think someday we could settle on the moon. We think it’s a fantastic location to place MoonMail, which ultimately will be a time capsule of our generation for future moon explorers.”

Chinese spacecraft reaches L2

The service module for China’s test lunar probe, that circled the Moon before returning to Earth, has reached L2 as planned.

As of Friday, the service module had been flying for 28 days, and was 421,000 kilometers away from Earth and 63,000 km from the moon. All experiments are going well. The service module was separated from the return capsule of China’s test lunar orbiter, which returned to Earth on Nov. 1 after circling the moon in its eight-day mission launched on Oct. 24.

…After two orbital transfers, the service module re-entered the elliptical orbit with an apogee of 540,000 km and a perigee of 600 km. During the flight, the service module again performed orbital transfer actions twice, and flew along the pre-set Earth-moon transfer orbit. On Nov. 23, it reached the perilune and with the lunar gravity it was able to undertake the orbit maneuver to fly to the L2 point.

This is brilliant management. They not only test return-to-Earth capability, they practice flying a robot ship in deep space, doing complex orbital maneuvers. In addition, depending on the equipment on the service module, they get a cheap unmanned probe for observing the near lunar environment.

Kickstarter campaign to fund lunar probe

The competition heats up: A private consortium of scientists and entrepreneurs is planning to fund its unmanned lunar lander with a Kickstarter campaign followed by private sales..

The mission is raising initial development funding through Kickstarter, the crowdfunding platform. Following the initial public phase the remaining funding requirements will be met through sales of ‘digital memory boxes’ in which donors can have their biographies recorded and taken to the Moon. These will also include a strand of hair so that their DNA can exist in space. The team has claimed that around one per cent of the global population who can afford a memory box will buy one. Also included in the time capsule will be record of life on Earth. The archive will include a record of human history and civilisation to date alongside a species database showing the biodiversity of animals and plants.

This is essentially a UK project, backed by the government but with little funding. They hope to launch in 2024, with two missions planned, the first to drill into the lunar soil and the second to bring back samples.

The Earth/Moon double planet, as seen by China’s Chang’e 5 probe

Earth/Moon as seen by Chang'e 5

China’s Chang’e 5 probe has taken a spectacular image of the Moon and Earth as it whips around the Moon on its circumlunar test flight.

Though China has released little additional information about the status of the mission, this image demonstrates that the vehicle is functioning well, sending back data, and that they are controlling its operation precisely and exactly as planned. The spacecraft is scheduled to return to Earth on November 1.

Meanwhile, China’s second lunar probe, Chang’e 2, now in solar orbit about 60 million miles from Earth, continues to operate four years after launch

LADEE impact site located

Lunar Reconnaissance Orbiter has spotted the impact crater formed when engineers sent the probe LADEE crashing into the lunar surface in April 2014.

Compared with asteroid and meteoroid impacts on the moon, LADEE was actually traveling pretty slow, ‘only’ 3,800 miles per hour (1,700 meters per second). That combined with the relatively low mass and density of the spacecraft, a fairly neat crater of only 10 feet (3 meters) across was created. The crater barely registered in LROC’s image resolution, making it a very difficult task to identify the fresh man-made divot.

Chinese lunar mission launches

The competition heats up: The Chinese have launched their next lunar mission, a fly-by around the Moon to test their return-to-Earth engineering in anticipation of a future sample return mission.

Chang’e 5-T1, one of the test models for Chang’e-5, was developed using a Chang’e 2 type spacecraft (acting like a service module) featuring the Chang’e-5 return capsule. This return capsule is very similar to the Shenzhou manned return technology, so it is assumed that it was developed using the Shenzhou as a baseline model. The service module will be used for trajectory corrections, power supply using two solar panels and batteries, along with telemetry and commands transmission to and from the control center.

Following launch, Chang’e 5-T1 will be injected into a lunar free-return orbit, loop behind the Moon once and return to Earth to test the high speed atmospheric reentry of a capsule returning from the translunar voyage at 11.2 km/s.

This launch marks the start of this nine day mission. Stay tuned for updates.

China to launch two payloads to the Moon

The competition heats up: On Thursday China plans to send a capsule on a mission around the Moon and back to Earth to test its heat shield.

The rocket’s upper stage, which will also round the Moon but not return to Earth, will also carry a privately funded cubesat designed to study the radiation levels during the entire journey.

Twenty minutes after launch on October 23, (at 1:59 p.m. U.S. Eastern time), the Long March’s upper stage will separate from the test capsule, and both will continue on a trajectory that takes them around the moon. The capsule will return to re-enter Earth’s atmosphere on October 31. In early discussions with the Chinese, LuxSpace was told that the upper stage [carrying the private cubesat] would re-enter the atmosphere as well, but it’s now expected to enter a wide, looping orbit around Earth. The main battery is only designed to last 10 days, although it may go longer.

Radio receivers on Earth will be able to tune in to 4M’s signal shortly after separation, and will be able to follow it as it rounds the moon, coming as close as 7,500 miles to the surface. The payload also includes a radiation sensor that will take measurements throughout the journey into Earth-moon space. Anyone with the proper equipment will be able to receive the compressed radiation data and decode it.

Though this private mission is definitely breaking new ground by sending a small payload to lunar space for very little money, the article is incorrect when it states that this is the first privately funded Moon mission. In 1997-1998 HGS 1, a Hughes commercial communications satellite that was placed in an incorrect orbit by a Russian rocket, was sent on a wide elliptical orbit to fly past the Moon twice and thus use this sling shot effect to get the satellite into a usable orbit.

Recent volcanism on the Moon

New data from Lunar Reconnaissance Orbiter suggests that lunar volcanism petered out slowly and occurred more recently that previously believed.

NASA’s Lunar Reconnaissance Orbiter (LRO) has provided researchers strong evidence the moon’s volcanic activity slowed gradually instead of stopping abruptly a billion years ago. Scores of distinctive rock deposits observed by LRO are estimated to be less than 100 million years old. This time period corresponds to Earth’s Cretaceous period, the heyday of dinosaurs. Some areas may be less than 50 million years old. Details of the study are published online in Sunday’s edition of Nature Geoscience. “This finding is the kind of science that is literally going to make geologists rewrite the textbooks about the moon,” said John Keller, LRO project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

In a way, this new conclusion is an example of science discovering the obvious. It seems to me quite unlikely that volcanic activity on the Moon would have “stopped abruptly” under any conditions. That’s not how these things work.

Yutu is slowly dying

China’s lunar rover Yutu, unable to move since its first few weeks on the moon, is slowly dying.

The rover is currently in good condition and works normally, but its control problem persists, said Yu Dengyun, deputy chief designer of China’s lunar probe mission. “Yutu has gone through freezing lunar nights under abnormal status, and its functions are gradually degrading,” Yu told Xinhua at an exclusive interview. He said that the moon rover and the lander of the Chang’e-3 lunar mission have completed their tasks very well. The rover’s designed lifetime is just three months, but it has survived for over nine.

As China’s first planetary rover mission, the limited roving success of Yutu is well balanced by its ability to continue functioning on the lunar survey for so long. The engineering data obtained from this mission will serve Chinese engineers well as they plan future missions.

Private lunar lander completes test landing

The competition heats up: One of the competitors in the Google Lunar X-Prize has successfully completed its first landing test, on Earth, of its lander.

The article does not really provide a lot of information about the test itself, spending most of its copy describing what the test was supposed to do. Still, they did complete it successfully, which means they will now revise, rebuild, and retest.

Russian umanned space program pushed back three years

Because of the increased workload imposed on Russia when the U.S. suddenly pulled out of the European ExoMars mission, the Russians have imposed a three year delay on their entire program of unmanned science probes.

Although all previously approved projects still remain on the table, the nation’s series of lunar missions face a domino effect of delays. Russia’s first post-Soviet attempt to land on the surface of the Moon was pushed back from 2016 to 2019. Known as Luna-Glob or Luna-25, the unmanned lunar lander was designed to test landing techniques for future lunar missions. On the political front, the successful landing of the Luna-Glob would be a signal to the international scientific community that Russia is back in the planetary exploration business after the 2011 fiasco of the Phobos-Grunt mission.

This report above is a more nuanced analysis than yesterday’s story about the presentation given by the head of the Russia’s Space Research Institute at Saturday’s science conference in Moscow. Today’s story gives the reasoning for the delays, as explained by the Russians themselves, as well as outlines the entire program more thoroughly.

The story describes a string of planned Russian lunar probes, beginning with Luna-Glob. This program was probably approved by the government when the U.S. decided to return to the Moon in 2004 under George Bush. The Russians don’t seem to be able any longer to be self-starters, but instead need the competition from the U.S. to get them jump-started.

Even so, while the U.S. has already flown most of the unmanned probes to the Moon that were proposed in 2004, the Russian program had not yet gotten off the ground.

How the Earth gave the Moon a lemon shape

Scientists have found that the Earth’s gravity combined with the Moon’s rotation forced the satellite to become “lemon-shaped.”

As the Moon solidified, its rotation caused it to elongate along its polar axis. But because the length of the Moon’s rotation was the same as its orbit, with one hemisphere always facing the Earth, the tidal force of the Earth’s gravity then pulled at the center, distorting the Moon’s shape so that one hemisphere bulged Earthward.

This theory is not new, but these new calculations are more robust, lending greater weight to it.

The first lunar close-up

Fifty years ago tomorrow Ranger 7 took the first close-up images of the Moon, just before the spacecraft crashed onto the surface.

“It was like looking at a soft quilt or something, no jagged edges on anything,” muses Jim Burke, as if he’s describing something every school kid hasn’t seen a hundred times. “It looked like fresh snow in a way, except it was grey instead of white.”

At the time—50 years ago tomorrow—Burke was one of the first people on Earth to see what the surface of the Moon looks like up close. Early on the morning of July 31, 1964, he joined his colleagues in poring over a series of printed photographs, the pockmarked Moon getting closer and closer until one final blurred image marked the moment when Ranger 7 impacted the surface, making its own brand-new crater. A stripe of static along one side of that last photo indicated the interruption of the final transmission.

The article details the frustrating history of the Ranger program, with the first six attempts all failing. Ranger 7 succeeded, however, working so well that the last image actually got truncated at impact. The full set of images revealed the surprising cratered history of the Moon, with the impact rate of large to small craters far more complex than expected.

Was Yutu stopped by rough ground?

One of the designers of the Chinese lunar rover Yutu said in a news interview today that the rocky nature of the Moon’s surface, far rougher than expected, was what caused it to stall.

The rover was tested in Beijing, Shanghai and the desert in northwestern China before its launch, but the terrain of the landing site proved to be much more rugged than expected, said Zhang Yuhua, deputy chief designer of the lunar probe system for the Chang’e-3 mission. “It is almost like a gravel field.”

Data from foreign researchers projected that there would be four stones, each above 20 cm, on average every 100 square meters, but the quantity and size of the stones that Yutu has encountered has far exceeded this expectation, Zhang said in an exclusive interview with Xinhua. “Experts’ initial judgement for the abnormality of Yutu was that the rover was ‘wounded’ by colliding with stones while moving,” she said. [emphasis mine]

The implication of the highlighted quote is that it isn’t their fault, it was the fault of those evil Americans and Russians who incorrectly estimated the roughness of the ground. This article also doesn’t fit the information released when Yutu first stalled, where they explained that their problem was partly an inability to retract equipment in preparation for lunar night. While this story could be true, it isn’t the whole story.

Looking Forward

In the past week there must have been a hundred stories written celebrating the 45th anniversary of Apollo 11. Here’s just a small sampling:

These articles try to cover the topic from all angles. Some looked at the wonders of the achievement. Others extolled the newspaper’s local community and their contribution. Some used the event to demand the U.S. do it again.

None of this interests me much. Though I passionately want humans, preferable Americans, back on the Moon exploring and settling it, this fetish with celebrating Apollo is to me becoming quite tiresome.
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