Posted on by Mark Thompson

Measuring How Much Dust Spacecraft Kick Up When they Land

The instrument called Radar Interferometry For Landing Ejecta set up inside of a vacuum chamber to simulate the atmosphere in space. Credit : University of Illinois

The arrival of spacecraft on alien worlds uses a number of different techniques from giant air bags to parachutes and small rockets. The use of rockets can pose a problem to onboard technology though as the dust kicked up can effect sensors and cameras and the landing site can be disturbed in the process. A team of researchers have developed a new instrument that can measure the dust that is kicked up on landing to inform future instrument design. 

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Posted on by Evan Gough

Incredible Descent Video of the Chinese Lander to the Lunar Far Side

China's Chang'e-4 lander on the lunar surface. Image Credit: CNSA/CLEP
China's Chang'e-4 lander on the lunar surface. Image Credit: CNSA/CLEP

On January 2nd, 2019, China’s Chang’e-4 lander made a successful landing on the far side of the Moon. The China National Space Administration (CNSA) and the Chinese Lunar Exploration Program (CLEP) report that after 9 days on the surface, the mission is in good shape. The Yutu-2 rover has been deployed and has begun exploring the Von Karman crater.

CNSA has released some video of the mission, including a video of Chang’e-4’s historic descent. Thanks to the hard-working people at the Planetary Society, and to Andrew Jones who reports on the Chinese Space Program, we have a handful of new videos and images of the Chang’e-4’s mission to enjoy.

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Posted on by Matt Williams

What Were the First Lunar Landings?

A picture of Earth taken by Apollo 11 astronauts. Credit: NASA

The moment that the Apollo-11 mission touched down on the Moon, followed by Neil Armstrong‘s famous words – “That’s one small step for [a] man, one giant leap for mankind” – is one of the most iconic moments in history. The culmination of years of hard work and sacrifice, it was an achievement that forever established humanity as a space-faring species.

And in the year’s that followed, several more spacecraft and astronauts landed on the Moon. But before, during and after these missions, a number of other “lunar landings” were accomplished as well. Aside from astronauts, a number of robotic missions were mounted which were milestones in themselves. So exactly what were the earliest lunar landings?

Robotic Missions:

The first missions to the Moon consisted of probes and landers, the purpose of which was to study the lunar surface and determine where crewed missions might land. This took place during the 1950s where both the Soviet Space program and NASA sent landers to the Moon as part of their Luna and Pioneer programs.

The Soviet Luna 2 probe, the first man-made object to land on the Moon. Credit: NASA
The Soviet Luna 2 probe, the first man-made object to land on the Moon. Credit: NASA

After several attempts on both sides, the Soviets managed to achieve a successful lunar landing on Sept. 14th, 1959 with their Luna-2 spacecraft. After flying directly to the Moon for 36 hours, the spacecraft achieved a hard landing (i.e. crashed) on the surface west of the Mare Serenitatis – near the craters Aristides, Archimedes, and Autolycus.

The primary objective of the probe was to help confirm the discovery of the solar wind, turned up by the Luna-1 mission. However, with this crash landing, it became the first man-made object to touch down on the Moon. Upon impact, it scattered a series of Soviet emblems and ribbons that had been assembled into spheres, and which broke apart upon hitting the surface.

The next craft to make a lunar landing was the Soviet Luna-3 probe, almost a month after Luna-2 did. However, unlike its predecessor, the Luna-3 probe was equipped with a camera and managed to send back the first images of the far side of the Moon.

The first US spacecraft to impact the Moon was the Ranger-7 probe, which crashed into the Moon on July 31st, 1964. This came after a string of failures with previous spacecraft in the Pioneer and Ranger line of robotic spacecraft. Prior to impact, it too transmitted back photographs of the Lunar surface.

The Ranger 7 lander, which became the first US spacecraft to land on the Moon. Credit: NASA
The Ranger 7 lander, which became the first US spacecraft to land on the Moon. Credit: NASA

This was followed by the Ranger-8 lander, which impacted the surface of the Moon on Feb. 20th, 1965. The spacecraft took 7,000 high-resolution images of the Moon before crashing onto the surface, just 24 km from the Sea of Tranquility, which NASA had been surveying for the sake of their future Apollo missions. These images, which yielded details about the local terrain, helped to pave the way for crewed missions.

The first spacecraft to make a soft landing on the Moon was the Soviet Luna-9 mission, on February 3rd, 1966. This was accomplished through the use of an airbag system that allowed the probe to survive hitting the surface at a speed of 50 km/hour. It also became the first spacecraft to transmit photographic data back to Earth from the surface of another celestial body.

The first truly soft landing was made by the US with the Surveyor-1 spacecraft, which touched down on the surface of the Moon on June 2nd, 1966. After landing in the Ocean of Storms, the probe transmitted data back to Earth that would also prove useful for the eventual Apollo missions.

Several more Surveyor missions and one more Luna mission landed on the Moon before crewed mission began, as part of NASA’s Apollo program.

Launch of Apollo 11. On July 16, 1969, the huge, 363-feet tall Saturn V rocket launches on the Apollo 11 mission from Pad A, Launch Complex 39, Kennedy Space Center, at 9:32 a.m. EDT. Onboard the Apollo 11 spacecraft are astronauts Neil A. Armstrong, commander; Michael Collins, command module pilot; and Edwin E. Aldrin Jr., lunar module pilot. Apollo 11 was the United States' first lunar landing mission. While astronauts Armstrong and Aldrin descended in the Lunar Module "Eagle" to explore the Sea of Tranquility region of the moon, astronaut Collins remained with the Command and Service Modules "Columbia" in lunar orbit. Image credit: NASA
Launch of Apollo 11 mission aboard a Saturn V rocket on July 16th, 1969. Credit: NASA

Crewed Missions:

The first crewed landing on the Moon was none other than the historic Apollo-11 mission, which touched down on the lunar surface on July 20th, 1969. After achieving orbit around the Moon in their Command Module (aka. the Columbia module), Neil Armstrong and Buzz Aldrin rode the Lunar Excursion (Eagle) Module down to the surface of the Moon.

Once they had landed, Armstrong radioed to Mission Control and announced their arrival by saying: “Houston, Tranquility Base here. The Eagle has landed.” Once the crew had gone through their checklist and depressurized the cabin, the Eagles’ hatch was opened and Armstrong began walking down the ladder to the Lunar surface first.

When he reached the bottom of the ladder, Armstrong said: “I’m going to step off the LEM now” (referring to the Lunar Excursion Module). He then turned and set his left boot on the surface of the Moon at 2:56 UTC July 21st, 1969, and spoke the famous words “That’s one small step for [a] man, one giant leap for mankind.”

About 20 minutes after the first step, Aldrin joined Armstrong on the surface and became the second human to set foot on the Moon. The two then unveiled a plaque commemorating their flight, set up the Early Apollo Scientific Experiment Package, and planted the flag of the United States before blasting off in the Lunar Module.

Aldrin on the Moon. Astronaut Buzz Aldrin walks on the surface of the moon near the leg of the lunar module Eagle during the Apollo 11 mission. Mission commander Neil Armstrong took this photograph with a 70mm lunar surface camera. While astronauts Armstrong and Aldrin explored the Sea of Tranquility region of the moon, astronaut Michael Collins remained with the command and service modules in lunar orbit. Image Credit: NASA
Buzz Aldrin on the Moon during the Apollo 11 mission, with the reflection of Neil Armstrong visible in his face plate. Credit: NASA

Several more Apollo missions followed which expanded on the accomplishments of the Apollo-11 crew. The US and NASA would remain the only nation and space agency to successfully land astronauts on the Moon, an accomplishment that has not been matched to this day.

Today, multiple space agencies (and even private companies) are contemplating returning to the Moon. Between NASA, the European Space Agency (ESA), the Russian Space Agency (Roscosmos), and the Chinese National Space Administration (CNSA), there are several plans for crewed missions, and even the construction of permanent bases on the Moon.

We have written many great articles about the Moon here at Universe Today. Here’s Who Were the First Men on the Moon?, How Many People Have Walked on the Moon?, How Do We Know the Moon Landing Isn’t Fake?, Where Were You When Apollo 11 Landed on the Moon?, What Does The Apollo 11 Moon Landing Site Look Like Today?

Want more information about the Moon? Here’s NASA’s Lunar and Planetary Science page. And here’s NASA’s Solar System Exploration Guide.

You can listen to a very interesting podcast about the formation of the Moon from Astronomy Cast, Episode 17: Where Did the Moon Come From?

Sources:

Posted on by Jason Major

Watch the Trailer for “The Last Man on the Moon”

Gene Cernan on the Moon during the final EVA of the Apollo 17 mission, Dec. 13, 1972 (NASA/JSC scan)

On December 14, 1972, at about 5:40 a.m. GMT, Apollo 17 astronaut Eugene Andrew “Gene” Cernan returned to the lunar module Challenger after the end of the third mission EVA to join Harrison “Jack” Schmitt, completing nearly two and a half days of surface operations within the Taurus-Littrow site and officially becoming the last human to set foot upon the lunar surface. No one has returned since, and to this day the 80-year-old Cernan still holds the title of “last man on the Moon.”

If that’s not the perfect setup for a documentary film, I don’t know what is. Luckily for us there’s one in the works.

“The Last Man on the Moon,” from UK-based Mark Stewart Productions, tells the story of Gene Cernan and his accomplishments against the backdrop of the Apollo era, when superpowers competed for dominance in space and hotshot flyboys became international heroes. With firsthand accounts from Cernan himself and his family, along with several other astronauts and NASA celebrities, it’s an emotional and intimate account of America’s last lunar voyage.

Watch the trailer below:

According to IMDB the 99-minute documentary directed by Mark Craig is slated for release in the UK (and hopefully U.S.!) sometime this year, although an exact date isn’t listed. There have been advance screenings very recently, at some of which Cernan was present for Q&A sessions. Some viewers are calling it “the best space documentary they have seen” so needless to say I’m pretty excited about it!

You can keep up with the status of the film (and see some exclusive astronaut photos) by liking the Facebook page here and joining the mailing list on the official site.

And yes, we do need more films like this.

“I really wanted to reach out, stick it in my spacesuit and bring it home and show it to everybody: this is what it feels like.”
– Gene Cernan

Earth over the LM seen from the Apollo 17 landing site (NASA/JSC scan)
Earth over the LM seen from the Apollo 17 landing site (NASA/JSC scan)

Video © Mark Stewart Productions. All rights reserved.

Posted on by Ken Kremer

Neil Armstrong; 1st Human on the Moon – Apollo 11, Tributes and Photo Gallery

Image Caption: On the Lunar Surface – Apollo 11 astronauts trained on Earth to take individual photographs in succession in order to create a series of frames that could be assembled into panoramic images. This frame from fellow astronaut Buzz Aldrin’s panorama of the Apollo 11 landing site is the only good picture of mission commander Neil Armstrong on the lunar surface. Credit: NASA

In memory of Neil Armstrong, First Man to set foot on the Moon, here’s a summary of Apollo 11 highlights and a collection of some tributes and photos to celebrate his life and the indelible inspiration he gave to current generations and all those yet to come to take up the noble torch for science and exploration. He became an everlasting icon for the ages when he took, “one giant leap for mankind”, and accomplished one of the greatest feats in human history.

Armstrong passed away at age 82 on Saturday, August 25, 2012 due to complications from heart bypass surgery.

Neil Armstrong was the commander of the three man crew of Apollo 11, which included Buzz Aldrin and Michael Collins.

Apollo 11 Crew. The Apollo 11 lunar landing mission crew, pictured from left to right, Neil A. Armstrong, commander; Michael Collins, command module pilot; and Edwin E. Aldrin Jr., lunar module pilot. Credit: NASA

The trio blasted off on their bold, quarter of a million mile moon mission from Cape Canaveral, Florida on July 16, 1969 to fulfill the lunar landing quest set by President John F. Kennedy early in the decade.


Armstrong and Aldrin safely touched down at the Sea of Tranquility on the lunar surface on July 20, 1969 as hundreds of millions across the globe watched in awe and united in purpose.

“Houston, Tranquility Base here. The Eagle has landed !,” Armstrong called out and emotional applause erupted at Mission Control – “You got a bunch of guys about to turn blue.”

Armstrong carried all of humanity with him when he stepped off the footpad of NASA’s Apollo 11 Lunar Module and became the first representative of the human species to walk on the surface of another celestial body.

His first immortal words,

“That’s one small step for [a] man, one giant leap for mankind.”

During their 2 ½ hours moonwalk Armstrong and Aldrin unveiled a plaque on the side of the lunar module. Armstrong read the words;

“Here men from the planet Earth first set foot upon the moon. July 1969 A.D. We came in peace for all mankind.”

The duo collected about 50 pounds (22 kg) of priceless moon rocks and set out the first science experiments placed by people on another world.

Altogether Armstrong and Aldrin spent about 21 hours on the moon’s surface. Then they said goodbye to the greatest adventure and fired up the LM ascent engine to rejoin Michael Collins circling above in the Apollo 11 Command Module.

Tributes to Armstrong have been pouring in – He is often described as a reluctant hero who gave credit to others.

“Armstrong, the lunar Adam,” wrote Virginia Adams

Armstrong and Aldrin plant the US flag on the Lunar Surface, July 1969. Credit: NASA

In a statement, NASA Administrator Charles Bolden said in part,

“As long as there are history books, Neil Armstrong will be included in them, remembered for taking humankind’s first small step on a world beyond our own.

“Besides being one of America’s greatest explorers, Neil carried himself with a grace and humility that was an example to us all. When President Kennedy challenged the nation to send a human to the moon, Neil Armstrong accepted without reservation.

“As we enter this next era of space exploration, we do so standing on the shoulders of Neil Armstrong. We mourn the passing of a friend, fellow astronaut and true American hero.”

Armstrong’s family released a statement that said in part;

“We are heartbroken to share the news that Neil Armstrong has passed away following complications resulting from cardiovascular procedures.

“Neil was our loving husband, father, grandfather, brother and friend.

“Neil Armstrong was also a reluctant American hero who always believed he was just doing his job. He served his Nation proudly, as a navy fighter pilot, test pilot, and astronaut. He also found success back home in his native Ohio in business and academia, and became a community leader in Cincinnati.

“For those who may ask what they can do to honor Neil, we have a simple request. Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink.”

“He was the best, and I will miss him terribly,” said Michael Collins, Apollo 11 command module pilot.

Buzz Aldrin, Apollo 11 lunar module pilot, released a statement that said in part,

“I am very saddened to learn of the passing of Neil Armstrong today. Neil and I trained together as technical partners but were also good friends who will always be connected through our participation in the Apollo 11 mission. Whenever I look at the moon it reminds me of the moment over four decades ago when I realized that even though we were farther away from earth than two humans had ever been, we were not alone. Virtually the entire world took that memorable journey with us.”

More photos of Neil Armstrong and crew at NASA here

Ken Kremer

Armstrong training on an X-15. Credit: NASA

Training for Apollo 11 on the Lunar Module. Credit: NASA

The Apollo 11 crew leaves Kennedy Space Center’s Manned Spacecraft Operations Building during the pre-launch countdown. Mission commander Neil Armstrong, command module pilot Michael Collins, and lunar module pilot Buzz Aldrin prepare to ride the special transport van to Launch Complex 39A where their spacecraft awaited them. Liftoff occurred at 9:32 a.m. EDT, July 16, 1969. Credit: NASA

Apollo 11 liftoff from Pad 39 at the Kennedy Space Center on July 16, 1969. Credit: NASA

Neil Armstrong about to become the first person to set foot on the lunar surface -TV camera view. Credit: NASA

Posted on by Jason Major

Best Views Yet of Historic Apollo Landing Sites

LROC image of the Apollo 11 landing site, acquired Nov. 5, 2011 (NASA/GSFC/Arizona State University)

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Just over 42 years after Neil and Buzz became the first humans to experience the “stark beauty” of the lunar surface, the Lunar Reconnaissance Orbiter captured the remnants of their visit in the image above, acquired Nov. 5, 2011 from an altitude of only 15 miles (24 km). This is the highest-resolution view yet of the Apollo 11 landing site!

The Lunar Module’s descent stage, a seismic experiment monitor, a laser ranging reflector (LRRR, still used today to measure distances between Earth and the Moon) and its cover, and a camera can be discerned in the overhead image… as well as the darker trails of the astronauts’ bootprints, including Armstrong’s jaunt eastward to the rim of Little West crater.

The crater was the furthest the Apollo astronauts ventured; in fact, if you take the total area Neil and Buzz explored it would easily fit within the infield of a baseball diamond!

Neil Armstrong’s visit to the crater’s edge was an unplanned excursion. He used the vantage point to capture a panoramic image of the historic site:

Panorama of the Apollo 11 site from Little West crater. (NASA)

“Isn’t that something! Magnificent sight out here.” Armstrong had stated before he was joined by Aldrin on the lunar surface. “It has a stark beauty all its own. It’s like much of the high desert of the United States. It’s different, but it’s very pretty out here.”

Previously the LROC captured the Apollo 15 landing site, which included the tracks of the lunar rover — as well as the rover itself! And, just yesterday, the LROC site operated by Arizona State University featured the latest similarly high-resolution view of the Apollo 12 site. This location has the honor of being two landing sites in one: Apollo 12 and the Surveyor 3 spacecraft, which had landed on April 20, 1967 – two and a half years earlier!

The Apollo 12 landing site in Oceanus Procellarum. (NASA/GSFC/Arizona State University)

Even though the US flag planted by Apollo 12 astronauts Pete Conrad and Alan Bean isn’t itself visible, the shadow cast by it is.

Apollo 12 was the only mission to successfully visit the site of a previous spacecraft’s landing, and it also saw the placement of the first Apollo Lunar Surface Experiments Package (ALSEP), which included a seismometer and various instruments to measure the lunar environment.

Read more about this image on the LROC page here, and check out the video tour below of the Apollo 12 site.

Images and video courtesy of NASA/GSFC/Arizona State University

Posted on by Nancy Atkinson

Did You Know: Russian Lunokhod Rovers Created Memorials on the Moon Honoring Women

Annotated graphic of Lunokhod 2's travels from Phil Stooke's International Atlas of Lunar Exploration.

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The saga of the Soviet Union’s Lunokhod moon rovers keeps getting more interesting! If you missed the update on our article about finding the “missing” Russian landers and rovers among the newly released Lunar Reconnaissance Orbiter images, the Lunokhod 2 rover was not exactly where one researcher initially thought – so there’s now an updated image, which you can see at this link. But among all the research and poring over images that has been done since NASA released six month’s worth of LRO data to the public earlier this week, Emily Lakdawalla from the Planetary Society uncovered an interesting tidbit about the Lunokhods which she generously passed on to me. After a little research, I found out more about an “extracurricular activity” the two Lunokhod rovers were commanded to do along their traverses on the lunar surface. They each created “memorials” to women on the Moon.

Since the early 1900’s, International Women’s Day has been observed each year by several countries around the world on March 8. The day marks the economic, political and social achievements of women. Russia has been celebrating this holiday since 1913, and in the 1970’s the crews who “drove” the Lunokhod rovers decided to honor women by commanding the rovers to create figure 8’s in the lunar regolith — 8 as in March 8.

Lunokhod 1. Credit: Goddard Spaceflight Center

Lunokhod 1 landed on the Moon November 17, 1970 and roved the surface for nearly a year (322 days.) Lunokhod 2 landed on January 15, 1973 and operated four months.

Apparently both rovers made a figure 8 in the regolith, although the documentation is a little fuzzy. A Russian scientist recalls that Lunokhod 1 made the figure 8, and one of the newly released LRO images shows a faint figure 8 in the regolith (see image left), which could only have been made by Lunokhod 1, but there is better documentation for Lunokhod 2’s memorial.

“To the extent I know, that was Lunokhod 1 which the crew made an 8 by Lunokhod tracks to congratulate our women on March 8 1973,” said Alexander “Sasha” Basilevsky, a veteran Russian planetary scientist, who responded to my queries about the significance of the figures 8’s. “Even in that Soviet time March 8 practically lost its political significance and we men just congratulated our women with little gifts. We continue to do this even now when our political system is far from communistic. For us it is just Women’s Day.”

Also, after scanning through all of Lunokhod 1’s panoramic images, I found this possible image of the figure 8, but I have not yet confirmed this is it:

Possible figure 8 in a Lunokhod 1 panoramic image. Credit: Laboratory of Comparative Planetology. Click image to see all the panoramas from Lunokhod 1.

See all the panoramas from Lunokhod 1.

Dr. Phil Stooke from the University of Western Ontario compiled “The International Atlas of Lunar Exploration.” “In my atlas I show a feature like this at Lunokhod 2’s site,” he said in response to my questions. “I didn’t know about this one at Lunokhod 1, but apparently it’s there as well.”

Here’s what Stooke wrote about the Lunokhod 2’s figure 8:

“On 18 January Lunokhod 2 was driven to a point on the north rim of the 25 m crater where it photographed the landing stage and the hill Le Monnier Alpha in the distance to the southwest. Here it was turned in place to create a circular mark with its wheels, and then moved a few meters where it made a second circle. The resulting figure 8 marking was later described as a memorial to commemorate International Women’s Day, 8 March, which was a holiday in the Soviet Union and is in Russia today.”

Addendum: Stooke told me that after seeing the new images from LRO, he will likely have to re-do the map of Lunokhod’ 2’s travels (top image). “Lunokhod images were often printed mirror-imaged left to right, and it’s often hard to know which is which,” he said. “In this case that map was constructed using at least one image the wrong way round, so it has to be corrected.”

So, it is unclear whether the decision to create these two memorials was in any way political, or simply a kind gesture by the Soviet space agency, or a unique choice made by the rover drivers, or – as was suggested to me by a couple of people – a visual play on an anatomical feature unique to women.

But more importantly, the accomplishments of the Lunokhod rovers are amazing considering the era in which they operated. While the Soviet Union’s exploration of the Moon was not well publicized outside of Russia — and now is often downplayed when compared to the Apollo missions – the ground-breaking technological achievements should be lauded for the innovative sample return missions and rovers that to this day hold the distance record that any vehicle has traveled on another celestial body. Together, they roved further than even the long-lasting Mars Exploration Rovers.

Lunokhod 1 Rover in its final parking spot, as seen by LRO. Credit: NASA/GSFC/Arizona State University. Click for larger version

Lunokhod 1 traveled 10.5 km (6.5 miles) and returned more than 20,000 TV images and 206 high-resolution panoramas. In addition, it performed twenty-five soil analyses with its x-ray fluorescence spectrometer and used its penetrometer at 500 different locations.

Lunokhod 2 covered a whopping 37 km (23 miles) of terrain, including hilly upland areas and rilles. It sent back 86 panoramic images and over 80,000 TV pictures. Many mechanical tests of the surface, laser ranging measurements, and other experiments were completed during this time.

Many thanks to Emily Lakdawalla, Phil Stooke and Alexander Basilevsky for helping me learn more about this interesting piece of space exploration history!

In case you are wondering, International Womans Day is an official holiday in Angola, Azerbaijan, Belarus, Burkina Faso, Cambodia, Equatorial Guinea, Eritrea, Georgia, Guinea Bissau, Kazakhstan, Kyrgyzstan, Laos, Moldova, Mongolia, Nepal, Russia, Tajikistan, Turkmenistan, Uganda, Ukraine, Uzbekistan.

See more about LRO images of Soviet lunar rovers.

More info on Lunokhod 1 and Lunokhod 2.

Posted on by John Carl Villanueva

Sea of Tranquility

Apollo 11 landed on the Moon on July 20, 1969.

The Sea of Tranquility is the landing site of Apollo 11, the mission that gave mankind its first ever walk on the Moon.

Walk? Yes, that’s right. The Sea of Tranquility is not actually a sea, so Neil Armstrong didn’t have to walk on water. In fact, there isn’t a single sea on the lunar surface. The Sea of Tranquility is actually a lunar mare. Now, although the plural of ‘mare’, ‘maria’, is a Latin word that means ‘seas’, these maria don’t have water in them.

Lunar maria were named as such because early astronomers mistook these areas as seas. You see, when you look at the Moon, particularly its near side (well, we don’t actually get to see the far side), i.e., the side which practically constantly stares at us at night, you’ll notice certain features that are darker than others.

Compare the Moon to a grey-scale model of the Earth, and you’ll easily mistake those dark patches for seas. By the way, in case you’ve been reading article titles (not the entire article) on this site lately, you might recall us mentioning water on the Moon. There’s water alright … underneath the surface, so even assuming that they’re plentiful, they don’t qualify as seas.

Let’s go back to our main topic. Called Mare Tranquillitatis in Latin, the Sea of Tranquility is found in the Tranquillitatis basin of the Moon and is composed of basalt. Maria are seen from Earth as relatively dark because the lighter colored areas are much elevated than them and hence are better illuminated by light coming from the Sun.

Whenever color is processed and extracted from multiple photographs, the Sea of Tranquility gives off a slightly bluish shade. This is believed to be caused by the relatively higher metal content in the area.

The actual landing site of Apollo 11’s lunar module is now named Statio Tranquillitatis or Tranquility Base. To the north of that specific area you’ll find three small craters aptly named Aldrin, Collins, and Armstrong, the privileged crew of Apollo 11.

The lunar module of Apollo 11 was not the only spacecraft to have landed on the Sea of Tranquility. There was also the Ranger 8 spacecraft … although “crash landed” is a more appropriate term. It wasn’t a failed mission though, since it was really meant to impact the lunar surface after taking pictures throughout its flight before striking the Moon.

Some people actually think the Apollo missions, particularly the lunar landings, were part of an elaborate hoax. Click on this link to read what the Japanese SELENE Lunar Mission discovered.

NASA has a huge collection of reliable links related to the Apollo missions.

Episodes about the moon from Astronomy Cast. Lend us your ears!

Shooting Lasers at the Moon and Losing Contact with Rovers
The Moon Part I