India’s Pragyan rover has successfully been deployed on the lunar surface


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According to a tweet from India’s space agency ISRO late yesterday, the Pragyan rover has successfully rolled down its ramp and is now deployed on the lunar surface.

No further updates have yet been released. According to ISRO’s mission webpage the instruments on both Vikram and Pragyan are as follows:

Lander payloads: Chandra’s Surface Thermophysical Experiment (ChaSTE) to measure the thermal conductivity and temperature; Instrument for Lunar Seismic Activity (ILSA) for measuring the seismicity around the landing site; Langmuir Probe (LP) to estimate the plasma density and its variations. A passive Laser Retroreflector Array from NASA is accommodated for lunar laser ranging studies.

Rover payloads: Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscope (LIBS) for deriving the elemental composition in the vicinity of landing site.

Pragyan’s two spectroscopes are likely similar to instruments on Curiosity and Perseverance on Mars, and allows some good surface analysis. Without a scoop however there will be no analysis of anything below the ground, unless the rover can upend a rock using its wheels.

India successfully lands Vikram on the Moon


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India this morning successfully placed its Vikram lander, carrying its Pragyan rover, on the surface of the Moon in the high southern latitudes.

I have embedded the live stream below, cued to just before landing.

The next challenge is getting Pragyan to roll off Vikram, and spend the next two weeks exploring the nearby terrain. The mission of both it and Vikram is only planned to last through the daylight portion of the 28-day-long lunar day, so it is not expected for either to survive the lunar night. Both will make observations, but the main purpose of this mission has already been accomplished, demonstrating that India has the technological capability to land an unmanned spacecraft on another planet. That the landing was in the high southern latitudes added one extra challenge to the mission.

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Russian engineers pinpoint approximate crash site of Luna-25

Russian engineers have pinpointed the approximate crash site of Luna-25 on the Moon as the 42-mile-wide crater Pontecoulant G, located at about 59 degrees south latitude, 66 east longitude.

Researchers from the Russian Academy of Sciences’ Keldysh Institute of Applied Mathematics have simulated the trajectory of the Luna-25 mission, figuring out where and when it crashed into the moon’s surface, the institute said in a statement on Telegram. “The mathematical modeling of the trajectory of the Luna-25 spacecraft, carried out by experts from the Ballistic Center of the Russian Academy of Sciences’ Keldysh Institute of Applied Mathematics, made it possible to determine the time and place of its collision with the moon,” the statement reads.

According to the institute, the spacecraft fell into the 42-kilometer Pontecoulant G crater in the southern hemisphere of the moon at 2:58 p.m. Moscow time on August 19.

The planned landing site, in Boguslawsky Crater at 73 degrees south latitude and 43 degrees east longitude, was many miles away.

Watch the landing attempt of Chandrayaan-3’s Vikram lander on August 23, 2023


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After separating from its Chandrayaan-3 propulsion module on August 17, 2023, India’s Vikram lunar lander has been slowly making orbital adjustments in preparation for its landing attempt on August 23rd.

I have embedded the live stream of that landing attempt below. As it is scheduled for 6:04 pm (India time), in India, in the U.S. that landing will occur in the early morning hours of August 23rd.

Following the failed crash on the Moon of Russia’s lunar lander Luna-25 yesterday, this landing attempt is likely to garner a lot more interest. It is also India’s second attempt, having failed in 2019 when its Vikram lander ran out of fuel before landing and crashed.
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Luna-25 lost after crashing on Moon

During its last major orbital burn, Luna-25’s engines apparently fired for longer than planned so that, instead of placing it into a lower orbit, the spacecraft was de-orbited and sent crashing onto the lunar surface.

The Russian space agency noted that all measures regarding the location of the spacecraft and establishing communications with it on August 19 and 20 yielded zero results. “Preliminary analysis results suggest that a deviation between the actual and calculated parameters of the propulsion maneuver led the Luna-25 spacecraft to enter an undesignated orbit and it ceased to exist following a collision with the surface of the Moon,” Roscosmos stated.

This is a tragedy for Russia, as this mission hoped to re-establish it as one of the major players in the exploration of the solar system. Instead, we once again have a data point suggesting significant quality control problems within Russia’s aerospace industry. Its misplaced focus on providing government jobs rather than actually building and quickly flying spacecraft and rockets results too often in failure.

Luna-25 fails to enter orbit for landing on Moon

Though it is in lunar orbit, Russia’s Luna-25 lander today was unable to perform an engine burn as planned to place it in its final orbit for landing.

“Today, in accordance with the flight program of the Luna-25 probe, at 2:10 p.m. Moscow time, a command was issued to the probe to enter the pre-landing orbit. During the operation an emergency occurred on the space probe that did not allow it to perform the maneuver in accordance with the required parameters,” Roscosmos said.

Engineers are analyzing the issue, but no other information was released.

This issue could simply be the spacecraft’s computer aborted the engine burn because it sensed something not right, and that after some correction another burn can follow later. Under this circumstance the landing attempt would simply be delayed.

It is also possible something happened during that engine burn, and the spacecraft is either in an incorrect orbit, or might even be lost entirely. Stay tuned.

Luna-25 takes first image of lunar surface

Luna-25's first lunar image
Click for interactive map. Zeeman is located on the lower left.

Russia’s state-run press today issued the first picture taken by Luna-25 after entering lunar orbit two days ago. That picture, to the right and cropped and reoriented to post here, shows part of Zeeman Crater at 75 degrees south latitude and 135 degrees west, on the far side of the Moon. From the TASS announcement:

“The Luna-25 spacecraft, flying in a circular orbit as the Moon’s artificial satellite, has taken pictures of the lunar surface with television cameras of the STS-L system. The image, taken today at 08:23 Moscow time, shows the southern polar crater Zeeman on the far side of the Moon. The coordinates of the crater center are 75 degrees south and 135 degrees west,” the state corporation said. Roscosmos said the Zeeman crater is of great interest to researchers. Its rim rises eight kilometers above its relatively flat floor.

The picture shows Zeeman’s southern rim to the left, with its pockmarked crater floor to the right. The crater the lander is targeting, Broguslawsky Crater, sits in the opposite hemisphere of Zeeman, slightly closer to the south pole but on the Moon’s near side.

Chandrayaan-3’s Vikram lander separates from its propulsion module; Luna-25 in lunar orbit


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The two probes aiming to land in the high southern latitudes of the Moon in the next week are now both in lunar orbit and preparing for their planned landings.

First India’s Chandrayaan-3: With its propulsion module having completed the job of getting Chandrayaan-3 from Earth to lunar orbit, the Vikram lander today separated from that module in preparation for firing its own engines on August 23, 2023 and landing on the Moon.

Vikram needs to make several orbital adjustments before that landing attempt.

Second, Russia’s Luna-25 probe entered lunar orbit yesterday, where it will spend the next few days making its own orbital adjustments before attempting its landing on August 21st.

Vikram carries a small rover, Pragyan. Luna-25 is only a lander, though it has a scoop and will do analysis of the lunar soil below it. Neither is landing “near the south pole”, as most news sources are saying. They are landing at latitudes comparable to landing in the Arctic on Earth, on the northern coast of Alaska. As such, neither will find out anything about the question of remnant ice in south pole’s permanently shadowed regions.

Chandrayaan-3 reaches final lunar orbit for landing


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India’s Chandrayaan-3 spacecraft completed its final lunar orbital engine burn today, placing it in the correct orbit to release the lander Vikram, carrying the Pragyan rover.

The release is scheduled for tomorrow, with the landing targeting August 23, 2023. This will be India’s second attempt to softland an unmanned probe on the Moon. The Vikram lander of Chandrayaan-2 failed in 2019 during its final engine burn above the surface, crashing thereafter. Engineers at India’s space agency ISRO spent several years upgrading that lander to better insure this new attempt would succeed.

The lander has been given more ability to manoeuvre during the descent, the mission allows for a bigger 4 km x 2.4 km area for landing, more sensors have been added, one of the thrusters has been removed, and the legs of the lander have been made sturdier to allow for landing even at slightly higher velocity. More solar panels have also been added to ensure that the mission can go on even if the lander does not face the sun. More tests to see the capability of the lander in different situations were carried out to make Chandrayaan-3 more resilient.

Both Vikram and Russia’s Luna-25 lander, scheduled for touchdown on August 21, will land in the high southern latitudes of the Moon, at about 70 degrees. They are not going to the Moon’s south pole, as many news reports claim.

Intuitive Machines sets mid-November launch date for its Nova-C lunar lander


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Intuitive Machines announced yesterday that the launch of its lunar lander, Nova-C, is now targeting a November 15-20, 2023 window, lifting off on a SpaceX Falcon 9 rocket.

The yellow dot on the map to the right indicates the landing site, Malapert A, in the southern latitudes of the Moon. The white cross indicates the south pole.

The lander had originally planned to launch in 2021, but delays in construction pushed the launch back two years. A second company, Astrobotics, has its own lander, Peregrine, that though also delayed two years, has been ready to launch since early this year. It won’t launch until the end of this year at the earliest, however, due to delays in readying its rocket, ULA’s Vulcan on its first flight.

Both India’s Chandrayaan-3 and Russia’s Luna-3 are right now on their way to the Moon, with each planning a landing next week.

China makes available to the international community Chang’e-5’s lunar samples

China on August 2, 2023 announced that it is now allowing scientists from all nations to apply for access to the lunar samples brought back to Earth by its 2020 Chang’e-5 mission to the Moon.

The announcement outlined very specific rules for the loan of the samples, including requirements that if any part of a sample needs to be destroyed to study it that action be videotaped in detail. Samples loaned for research are for one year periods only, though this can be extended.

The rules also allow two month loans for the use of samples in public display, such as at a museum.

In both cases China will closely supervise the research and retain the right to recall the samples at any time if it doesn’t approve of what the borrower is doing.

U.S. law forbids our government officials or agencies from working with China, so don’t expect NASA or its scientists to apply for these samples. However, the law doesn’t apply to independent scientists, though serious state department regulations would apply. I therefore doubt many American scientists will apply for any samples. It would carry too many risks to their other research.

Chandrayaan-3 completes next-to-last orbital maneuver before releasing Vikram lander


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According to India’s ISRO space agency, its Chandrayaan-3 spacecraft has successfully completed the next-to-last orbital maneuver burn before releasing Vikram lander, lowering the spacecraft’s orbit around the Moon to 150 by 177 kilometers.

Today’s maneuver can be considered the second last vital maneuver. The one that takes place on August 16, will set the course for the Vikram lander.

Based on how today’s and August 16’s manoeuvres are executed, ISRO will get to decide where the Vikram lander touches down, among three predesignated spots on the Moon’s surface.

It had been my understanding that the landing zone was as indicated by the red dot on the map to the right. It might be instead that was only one of three potential landing sites. If so, I will update the map when more data is released.

Russia launches Luna-25 to the Moon


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After almost two decades of development, Russia today used its Soyuz-2 rocket to launch Luna-25, its first lander to the Moon since the 1970s.

The link is cued to the live stream, just prior to launch. It will take several days to get to the Moon and enter orbit, make some orbital adjustments, then land in Boguslawsky crater, as shown on the map to the right. It is likely its landing will occur before India’s Chandrayaan-3 lands on August 23rd but not certain, depending on the adjustments needed in lunar orbit. Both could even land on the same day.

The leaders in the 2023 launch race:

54 SpaceX
33 China
11 Russia
6 Rocket Lab
6 India

American private enterprise still leads China in successful launches 62 to 33, and the entire world combined 62 to 55, while SpaceX by itself now trails the entire world (excluding American companies) 54 to 55.

South Korea’s KARI space agency releases new images taken by its Danuri lunar orbiter

To celebrate the anniversary of its launch, South Korea’s KARI space agency today released new images taken by its Danuri lunar orbiter.

Images include views of Reiner Gamma, a so-called swirl, which features a localized magnetic field and marks a bright spot within the Oceanus Procellarum region. Another shows shadows inside Amundsen Crater, close to the lunar south pole and a potential landing site for NASA’s Artemis 3 mission, which is slated to put astronauts on the moon in late 2025.

Another southern feature captured by Danuri is Drygalski Crater, showing the central peak inside the impact crater.

NASA engineers still struggling to understand why Orion’s heat shield ablated so much

NASA engineers still do not understand why the heat shield on its Orion capsule ablated as it did during its return to Earth on the first unmanned Artemis-1 mission.

The agency is still running tests. It also expressed confidence that the issue will not delay the Artemis-2 mission, the first intended to carry humans on SLS and in Orion and still scheduled for late 2024.

At the same time, agency officials hinted that the third Artemis mission, which has always been planned as putting humans on the Moon for the first time since Apollo, might not achieve that goal. It is still not clear whether the mission’s lunar spacesuits as well as SpaceX’s Starship lunar lander will be ready on time. The latter is facing serious regulatory problems imposed by the Biden administration that is generally preventing it from flight testing the spacecraft.

That second Artemis mission, the first planned to carry humans, is one that actually at present carries the most risk. It will not only use a heat shield that at present engineers do not entirely understand, it will be the first Orion capsule to have the environmental systems necessary for its human cargo. NASA is putting humans on the first test flight of those systems.

ISRO releases first images of the Moon from Chandrayaan-3

The Moon as seen by Chandrayaan-3

India’s space agency ISRO yesterday released the first images taken of the Moon by Chandrayaan-3, soon after entering lunar orbit.

The picture to the right is a screen capture from the short movie the agency compiled from those images, available at the link. The pictures were taken on August 5th, during the engine burn that put the spacecraft into lunar orbit. A solar panel can be seen on the left, with the cratered lunar surface to the right.

Chandrayaan-3 is presently undergoing a series of engine burns to lower its orbit in preparation for a planned August 23rd lunar landing in the high southern latitudes of the Moon.

Chandrayaan-3 enters lunar orbit


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India’s Chandrayaan-3 spacecraft today successfully entered lunar orbit, where it will spend the next week or so slowly lowering its orbit in preparation for a landing attempt by its Vikram lander on August 23rd.

Chandrayaan-3 began a roughly 30-minute burn around 9:30 a.m. Eastern, seeing the spacecraft enter an elliptical lunar orbit, the Indian Space Research Organization (ISRO) stated via social media. “MOX, ISTRAC, this is Chandrayaan-3. I am feeling lunar gravity,” ISRO Tweeted. “A retro-burning at the Perilune was commanded from the Mission Operations Complex (MOX), ISTRAC, Bengaluru.”

The spacecraft will gradually alter its orbit with a burn to reduce apolune Sunday, Aug. 6. It will settle into a 100-kilometer-altitude, circular polar orbit on Aug. 17. From here, the Vikram lander will separate from the mission’s propulsion module and enter a 35 x 100-km orbit in preparation for landing.

If the landing attempt is successful, the Pragyam rover will roll off Vikram to operate for about two weeks on the lunar surface in the high southern latitudes of the Moon.

Meanwhile, the Russian lander Luna-25 will launch on August 10th. Since the rocket that launches it and engines it carries are larger than that used by Chandrayaan-3, it will likely land in Boguslawsky crater, before Vikram touches down nearby.

Chandrayaan-3 is now on its way to the Moon

Chandrayaan-3's mission profile

According to a tweet from India’s space agency, ISRO, engineers have successfully completed the trans-lunar-injection burn that has now sent its Chandrayaan-3 lunar lander/rover on its way to the Moon.

As shown in mission’s profile graphic to the right, the spacecraft spent the last two weeks in Earth orbit. repeatedly raising its orbit to reduce the amount of fuel necessary to send it to the Moon. It will now take about five days traveling to the Moon, entering its orbit on August 5th. It will then spend about two weeks lowering that orbit slowly, until it is in the proper orbit for the descent to the surface on August 23, 2023.

If all goes well, its Vikram lander will gently place the Pragyan rover in the high southern latitudes, where it will function for about two weeks, or during the daylight portion of one lunar day.

NASA changes have cost Northrop Grumman $36 million on its Lunar Gateway module

Northrop Grumman yesterday revealed that unexpected requirement changes to the specifications of its HALO module for NASA’s Lunar Gateway space station has raised its cost for this fixed price contract by $36 million.

In the company’s fiscal second quarter financial results released July 27, the company announced an unfavorable estimate-at-completion adjustment of $36 million for its work on the Habitation and Logistics Outpost (HALO) module, one of the first elements of the Gateway. The company blamed the charge on “evolving Lunar Gateway architecture and mission requirements combined with macroeconomic challenges” that caused cost growth on the program.

…“We think that is best applied for commercial items or production programs with stable requirements and mature designs,” [the company’s CEO] said of fixed-price contracts. “As it’s turning out on the HALO program, the requirements are not as stable as we or the government anticipated, and we’re working with them to address that change management as we go forward.”

The HALO module was an upgrade of the company’s Cygnus cargo freighter, with its original fixed-price contract for $935 million.

On a fixed-price contract, NASA is not supposed to change its specifications. The company gets somewhat general requirements from NASA, and then builds the product to its own specifications. It appears that either NASA managers don’t seem to understand this and are causing the company problems, or the company itself had not anticipated some design and construction issues before bidding and are struggling to address them now. In the latter case Northrop Grumman managers might have themselves not understood the nature of fixed-price contracts, and had assumed NASA would simply pick up any increase in the project’s budget, as it does in cost-plus contracts. It apparently is not, and thus this old big space company is now suddenly forced to face reality.

NASA awards 11 small development contracts to a variety of companies

Capitalism in space: NASA today announced that it has awarded small contracts to eleven different companies, ranging from big established companies like ULA and Lockheed Martin to small startups like Varda and Zeno, for developing a range of new technologies, from power production on the Moon to making building materials from lunar soil.

Five of the technologies will help humanity explore the Moon. For astronauts to spend extended periods of time on the lunar surface, they will need habitats, power, transportation, and other infrastructure. Two of the selected projects will use the Moon’s own surface material to create such infrastructure – a practice called in-situ resource utilization, or ISRU. Redwire will develop technologies that would allow use of lunar regolith to build infrastructure like roads, foundations for habitats, and landing pads.

Blue Origin’s technology could also make use of local resources by extracting elements from lunar regolith to produce solar cells and wire that could then be used to power work on the Moon.

Astrobotic’s selected proposal will advance technology to distribute power on the Moon’s surface, planned to be tested on a future lunar mission. The company’s CubeRover would unreel more than half a mile (one kilometer) of high-voltage power line that could be used to transfer power from a production system to a habitat or work area on the Moon.

The contracts range in price from $1.6 to $34.7 million, with Blue Origin getting that largest award.

Chandrayaan-3 completes fourth engine burn in Earth orbit

Chandrayaan-3's mission profile

According to India’s space agency ISRO, engineers have successfully completed the fourth of about six engine burns designed to raise Chandrayaan-3’s Earth orbit in preparation for sending it on its path to the Moon.

As shown in the graphic to the right, these adjustments are relatively small, but each increases the speed of the spacecraft at its orbit’s closest point to the Earth. That extra velocity thus reduces the amount of fuel needed for that trans-lunar-injection burn.

If all the maneuvers continue to go as planned, the landing attempt will occur around August 23, 2023.

South Korean researchers turn simulated lunar soil into building blocks

Using simulated lunar soil, South Korean researchers have developed the engineering that turns that soil into building blocks shaped as needed.

The researchers first produce simulated moon soil by grinding black volcanic rock from Cheorwon County bordering the North. They then use a microwave to turn the sand-like simulant into solidified blocks. Lee said the team has developed a technique to make blocks by heating the soil in a mold to more than 1,000 degrees Celsius in two to three hours and cooling them. In space, the process could be powered by nuclear energy.

The article at the link also provides a nice summary of the status of South Korea’s entire space effort.

Venezuela officially signs onto Chinese lunar base project

Venezuela on July 17, 2023 officially signed an agreement with China to participate in China’s lunar base project.

Venezuela is the first nation, after Russia, to sign on to the project.

Since Venezuela has no space industry and is a bankrupt socialist state that can barely feed its people, this at first glance appears to merely be an effort by China for some international PR. One detail from the article however tells us what the deal is really about: “Venezuela will make its satellite control ground station infrastructure available for lunar missions.” In exchange for providing Venezuela some minor educational aid, China gets use of the ground stations that presently exist in Venezuela, and likely the right to build its own there as well.

Chandrayaan-3 completes second orbital maneuver

Chandrayaan-3's mission profile

According to India’s space agency ISRO, its lunar lander/rover Chandrayaan-3 today completed second orbital maneuver, raising the spacecraft’s orbit around the Earth from 41,762 by 173 kilometers to 41,603 x 226 kilometers.

The graphic to the right shows the entire mission profile of Chandayaan-3. It still has three more orbital adjustments to make in Earth orbit before it does its trans-lunar-injection burn to send it to the Moon. Once it arrives in lunar orbit it will then have to make six orbital adjustments to lower its orbit before making the descent to the surface.

The lunar landing itself is presently scheduled for August 23, 2023.

India successfully launches Chandrayaan-3


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India today successfully launched its Chandrayaan-3 lunar lander/rover probe toward the Moon, carried aloft by its LV-M3 rocket (a variation of its GSLV) from its coastal spaceport in Sriharikota.

Chandrayaan-3 carries the Vikram lander, which will bring the Pragyan rover to the surface. Pragyan will spend about two weeks operating on the lunar surface. The location is indicated by the red dot on the map to the right, in the high southern latitudes. The white cross marks the lunar south pole. Russia’s Luna-25 is scheduled to launch sometime in mid-August.

It will take time to get Chandrayaan-3 into the right lunar orbit for landing, which is presently scheduled for August 13, 2023.

For India this was its fifth successful launch for the year, the most since 2019, before it panicked over COVID. The leaders in the 2023 launch race:

46 SpaceX
26 China
9 Russia
5 Rocket Lab
5 India

American private enterprise still leads China in successful launches 52 to 26, and the entire world combined 52 to 45, while SpaceX by itself still leads the rest of the world (excluding other American companies) 46 to 45.

July 12, 2023 Quick space links

Courtesy of BtB’s stringer Jay.

 

  • China unveils proposed plan for first manned lunar mission before 2030
  • The plan calls for separate rockets, one for the manned ascent/descent Earth capsule, and the second for the lunar lander/ascent spacecraft. The two will rendezvous and dock in lunar orbit. This is all engineering by powerpoint at this point, though based on China’s track record I’d give it more credence than most of NASA’s recent promises.

 

The Earth and Moon, as seen by Mars Express in Mars orbit

The Earth and Moon, as seen from Mars
Click to see four image movie.

The science team for Europe’s Mars Express orbiter recently turned the spacecraft’s camera upward to capture a sequence of four images of the Earth with the Moon circling around it.

The images were taken at 14:08, 03:10 and 19:49 UTC on 15, 21, 27 May 2023 respectively, and at 15:00 UTC on 2 June 2023. This covers a bit more than half of the Moon’s monthly motion around the Earth. The distance between Earth and Mars varied from 279 186 624 km to 301 016 265 km during this time. The image resolution is about 2570 km per pixel.

To the right is the June 2nd image, cropped and enhanced to post there. The Earth is the larger spot to the left. The picture gives a sense of what the Earth-Moon double planet system looks like from Mars. Unlike all other planets, where the size difference between planet and moon is great, the Earth/Moon system is comprised of a Moon quite large in comparison to its central planet.

ISRO completes launch rehearsal for Chandrayaan-3’s launch on July 14th


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India’s space agency ISRO yesterday completed a full launch dress rehearsal of its Launch Vehicle Mark-3 rocket (LV-M3), in preparation for its July 14, 2023 launch that will put Chandrayaan-3 on its way to the Moon, India’s second attempt to soft land on another world.

More information here. The spacecraft will not reach the Moon until mid-August, and if all goes as planned, the lander Vikram will attempt its landing on August 23rd. If successful, the Pragyan rover will roll off the lander and begin exploration lasting about two weeks, or one lunar day. It is not designed to survive the long lunar night.

The LV-M3 rocket is simply the most powerful variation of India’s Geosynchronous Launch Vehicle (GSLV) rocket, capable of putting large payloads into space or sending probes to other planets.

Large mass of granite unexpectedly detected on Moon

Using archival data from four lunar orbiters (two American and two Chinese), researchers have unexpectedly detected evidence suggesting the existence of a large 20-mile-wide mass of granite under a lunar volcanic caldera.

“We have discovered extra heat coming out of the ground at a location on the Moon believed to be a long dead volcano which last erupted over 3.5 billion years ago. It’s around 50km across, and the only solution that we can think of which produces that much heat is a large body of granite, a rock which forms when a magma body – the unerupted lava – below a volcano cools. Granite has high concentrations of radioactive elements like uranium and thorium compared to other rocks in the lunar crust, causing the heating we can sense at the lunar surface”.

Except for some small grains found in Apollo lunar samples, granite has not been found anywhere in the solar system except on Earth. This discovery, if confirmed, will strengthen the theory that the Moon was once part of the Earth and was created from the impact of a second large body.

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