Tag: Vikram

India’s Vikram lander disturbed the lunar surface the least of all landers

9:29 am

According to an analysis of images taking before and after landing, engineers have concluded that India’s Vikram lander disturbed the lunar surface the least of all landers, due to its use of multiple smaller landing engines.

Presenting the new findings at LPSC on Monday, [ISRO scientist Suresh K] attributed the intriguingly short dust plume to the lack of a central engine on the spacecraft, which resulted in a lower engine thrust during descent. Starting its “rough braking phase” at an orbit of 18.6 miles (30 kilometers) above the lunar surface, when the spacecraft reached 0.4 miles (0.8 kilometers) above its targeted landing area, it switched off two of its four 800-newton engines such that two diagonal engines remained operational all the way until touchdown. The mission used the “least powerful engine till date,” [Suresh] K said. “We’ve observed very less disturbance on the surface.”

You can read their paper here [pdf].

Finding ways to reduce the dust kicked up during landings will be critical for the early missions to the Moon, before landing pads can be constructed. This research suggests that when Starship lands, it should use only its outer engines, and gimbal them sideways, in order to reduce the dust thrown up around it.

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LRO takes image of Vikram on Moon

9:02 am


Click for interactive map. To see the original
image, go here.

The science team for Lunar Reconnaissance Orbiter (LRO) yesterday released an oblique image taken of India’s Vikram lander, on August 27, 2023, four days after the lander touched down about 370 miles from the south pole.

The LROC (short for LRO Camera) acquired an oblique view (42-degree slew angle) of the lander. … The bright halo around the vehicle resulted from the rocket plume interacting with the fine-grained regolith (soil).

That image is shown in the inset to the right. I have cropped it to focus on Vikram itself, which is in the center of the inset, with its shadow to its right, the opposite of all the surrounding craters. Pragyan is in this image, but neither it nor its tracks appear visible. The rover had moved west from the lander, which would be downward to the line of three craters near the bottom of the inset. To get a better sense of Pragyan route, compare this image with the map India’s space agency ISRO released on September 2nd.

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Engineers had Vikram do short flight hop prior to shutting down

8:36 am

Indian engineers revealed today that prior to putting the Vikram lander to sleep for the long lunar night, they had the lander use its rocket engines to do a short up and down flight. From the first link:

“On command it (Vikram lander) fired the engines, elevated itself by about 40 cm as expected and landed safely at a distance of 30 to 40 cm away,” ISRO said in an update on ‘X’.

Before doing the hop engineers stored Vikram’s instruments and rover ramp, then redeployed them afterward to gather a tiny bit of new data before putting everything into hibernation.

The hop test proved that Vikram’s engines could be restarted even after being on the Moon for almost two weeks, and thus could potentially be used on a future sample return mission. It also suggested a future mission could choose to change its landing site periodically by use of its landing engines.

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Pragyan rover moves more than 300 feet away from Vikram

11:01 am

Map of Pragyan's traverse
Click for original image.

India’s space agency ISRO today released a map, shown to the right, that shows the entire traverse so far completed by its Pragyan rover in the Moon’s high southern latitudes. It has so far traveled more than 100 meters, or 300 feet, and continues to operate as planned.

The part of the traverse just south of the Vikram lander is where the lander filmed the rover doing several quick maneuvers and a 360 degree spin as engineers tested its operation before heading out on a longer journey. The rover’s image of the crater that the rover avoided, though released first, was actually taken afterward, after the rover had moved to the west.

Lunar sunset is in two days. Though engineers are preparing both Vikram and Pragyan for hibernation during that long lunar night, neither was designed to survive that extreme environment.

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Vikram takes movie of Pragyan rover as it roves

9:30 am

Pragyan as seen by Vikram
Click for movie.

Using one of Vikram’s lander cameras, engineers have produced a short movie of India’s Pragyan rover as it rotated to avoid a small crater about ten feet ahead.

The picture to the right is from that 16-second movie, near its end. It appears that the engineers operating Pragyan were unhappy with almost any route ahead from its present position, as they rotated Pragyan almost 360 degrees, and even attempted forward motion at one point and then resumed rotation.

It is not clear if any of the craters visible in this picture are the crater that caused the detour. The movie however does provide a sense of scale. Pragyan is small, but it is able to maneuver easily using its six wheels.

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Pragyan snaps first pictures of Vikram sitting on the Moon

8:28 am

Vikram as seen by Pragyan
Click for original image.

India’s space agency ISRO has released the first two pictures from the Pragyan rover showing the Vikram lander that bought both to the Moon safely.

The picture to the right is the close-up image, which shows two of Vikram’s science instruments. CHASTE is a probe that has been measuring the temperature of the Moon’s regolith at this spot, while ILSA is a seismometer for measuring the seismicity around the landing site.

Both spacecraft have been on the lunar surface now for one week, which means they are both halfway through their nominal two-week mission that lasts until lunar sunset, occurring on September 4th. Neither were designed to survive the 14-day-long lunar night, though engineers will attempt to kept both alive.

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Vikram finds temperatures of lunar soil varies significantly, depending on depth

9:17 am

Temperature range of soil at Vikram landing site

Based on data from one of the instruments on India’s lunar lander Vikram, scientists have found that the temperatures of the lunar soil at the landing site vary significantly, depending on depth. The temperature dropped from 55 degrees Celsuis to -10 degrees Celsuis when going from about 10 millimeters above the surface to about 82 millimeters below the surface, as shown in the graph to the right.

That’s equivalent from going from a summer day in Death Valley of 131 degrees Fahrenheit to a winter day in Minnesota of 14 degrees Fahrenheit, in a distance of only about 3.5 inches. While it was expected that there would a temperature drop, it appears the quick temperature drop just below the surface was faster than expected.

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Both Vikram and Pragyan functioning as planned on the Moon

9:29 am

Pragyan on the Moon
Click to see full movie.

According to tweets from India’s space agency ISRO, both the Vikram lander and the Pragyan rover are functioning as planned on the lunar surface, with the rover successfully activating its two science instruments.

The image to the right, taken by Vikram, shows the rover as it completed its roll down the ramp onto the lunar surface. This is a screen capture from a movie showing that roll down, which you can see by clicking on the picture. Since then it has moved another 26 feet from the lander.

I must add once again that Vikram did not land “on the south pole”, as too many so-called news organizations have been falsely claiming. It landed at about 69 degrees south latitude, quite a distance from that pole, in a flat region with no permanently shadowed craters. It is not specifically looking for water, though its instruments might help explain the orbital data that suggests there are areas on the surface of the Moon where hydrogen is somehow present.

If so many news outlets can’t seem to get these very basic facts about this mission correct, one must ask what else do they get wrong routinely? I don’t ask, because I always assume their information is wrong, check it constantly, and find repeatedly that they get numerous basic facts incorrect, especially when it comes to reporting on politics.

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

9:23 am


Click for interactive map.

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.

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India successfully lands Vikram on the Moon

9:10 am


Click for interactive map.

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

9:39 am


Click for interactive map.

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.
» Read more

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

9:08 am


Click for interactive map.

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.

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Chandrayaan-3 reaches final lunar orbit for landing

9:12 am


Click for interactive map.

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.

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

9:31 am


Click for interactive map.

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.

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ISRO releases first images of the Moon from Chandrayaan-3

10:23 am

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.

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Chandrayaan-3 enters lunar orbit

9:38 am


Click for interactive map.

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.

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Chandrayaan-3 is now on its way to the Moon

9:11 am

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.

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Chandrayaan-3 completes fourth engine burn in Earth orbit

9:04 am

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.

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Chandrayaan-3 completes second orbital maneuver

9:32 am

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.

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India successfully launches Chandrayaan-3

8:35 am


Click for interactive map.

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.

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

9:10 am


Click for interactive map.

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.

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India’s first private rocket company prepares for its first test suborbital launch

9:23 am

Skyroot, India’s first startup private rocket company, has now scheduled the first test launch of a suborbital version of its Vikram rocket for sometime between November 12the and 16th, depending on weather.

The rocket will be sent into space from ISRO’s Satish Dhawan Space Centre spaceport in Sriharikota, off the Andhra Pradesh coast.

The space sector was opened up to facilitate private sector participation in 2020. In 2021, Skyroot became the first space technology startup to ink an MoU with ISRO for sharing facilities and expertise.

…The company’s COO & co-founder, Naga Bharath Daka, said “The Vikram-S rocket getting launched is a single-stage sub-orbital launch vehicle, which would carry three customer payloads and help test and validate the majority of technologies in our Vikram series of space launch vehicles.” The four-year-old Skyroot has successfully built and tested India’s first privately developed cryogenic, hypergolic-liquid, and solid fuel-based rocket engines. The R&D and production activities extensively use advanced composite and 3D-printing technologies.

The company has raised $51 million in private investment capital, the most ever raised by a private Indian rocket company.

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ISRO to launch Chandrayaan-3 lunar lander mission in August

9:33 am

The new colonial movement: India’s space agency ISRO today announced that it has scheduled the launch of its Chandrayaan-3 lunar lander mission for August 2022.

The launch date was revealed by a government official, who also said that this launch will be one of eight total by India in 2022. If that number is completed, it would be the most India has ever accomplished in a single year, topping the seven launches that lifted off in 2018. It would also signal that India has finally put aside its fear of COVID that has shut down its aerospace industry for the last two years.

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India’s new Vikram lunar lander almost ready for launch

9:41 am

The new colonial movement: India’s new Vikram lunar lander, planned for launch later this year on Chandrayaan-3, is now undergoing final tests and assembly.

All payloads for tracking the lunar activity, the alpha-particle X-ray spectrometer and the ChaSTE — the lone instrument to touch the lunar surface to perform thermal measurements of lunar high-latitude regions — and others are being integrated with the rover. These are getting ready for tests and launch later this year,” said Kiran Kumar, who is currently the chairman of the Physical Research Laboratory (PRL) Council and a member of the Apex Science Board of the ISRO.

A launch date has not yet been set. Moreover, for this mission to fly India has got to get its rocket program flying again. It has been essentially shut down for two years because of its panic over the Wuhan virus.

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Indian private company test fires its own solid rocket motor

9:00 am

Capitalism in space: Skyroot Aerospace, an Indian private company, has successfully test fired its own privately-built solid rocket motor, as part of an effort to develop its own private rocket dubbed Vikram, with its first launch set for December ’21.

The solid rocket motor is for either the rocket’s second stage or for strap-on boosters. The company has already successfully tested the first stage engines.

The most interesting quote from the story however is this:

Founded by former scientists of the Indian Space Research organization (ISRO), Skyroot has raised $4.3 million till now and is in process of raising another $15 mn in 2021. In the past the company has raised investments from: Mukesh Bansal (Founder Myntra, CureFit), Solar Industries (India’s largest explosives manufacturer and renowned Space & Defence Contactor), Vedanshu investments and a few other Angel investors.

The Modi government has been making a strong effort to mimic the transition that NASA has gone through in the past decade whereby it shifts from having all its spacecraft and rockets designed, built, and owned by the government to having the government act merely as the customer buying those products from privately-run and independent companies. Like NASA, there has been strong resistance to this change within India’s government bureaucracy. Skyroot’s success, including its foundation by former ISRO engineers, is a very good sign that they are overcoming that resistance.

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India releases Vikram failure report

9:30 am

India’s space agency ISRO has released its investigation report on the failure of its lunar lander Vikram on September 7, 2019 to soft land on the Moon.

The Chandrayaan-2’s Vikram lander ended up spinning over 410 degrees, deviating from a calibrated spin of 55 degrees, and making a hard landing on the moon, according to ISRO scientists. The anomaly, which occurred during the second of four phases of the landing process, was reflected in the computer systems in the mission control room, but ISRO scientists could not intervene to correct it as the lander was on autonomous mode, using data already fed into its system before the start of the powered descent.

According to the report, they are using what was learned to incorporate changes in Chandrayaan-3, their next attempt at putting a lander and rover on the Moon, presently scheduled to launch 14 to 16 months from now. That launch date, about six months later than previous reports, also seems more realistic. Initially the agency was saying it planned to launch Chandrayaan-3 in less than a year from project inception, by November 2020, a schedule that seemed rushed and ripe for mistakes.

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Crash site of Vikram found

4:09 pm

Vikram impact point
Click for full image.

Using a mosaic of Lunar Reconnaissance Orbiter (LRO) images, citizen scientist Shanmuga Subramanian located on the Moon the debris and impact point for India’s Vikram lander that crashed there in September, an identification that has since been confirmed by LRO scientists.

The image on the right, reduced to post here, has been modified by the scientists to bring out the features that changed before and after the impact.

After receiving this tip the LROC team confirmed the identification by comparing before and after images. When the images for the first mosaic were acquired the impact point was poorly illuminated and thus not easily identifiable. Two subsequent image sequences were acquired on 14, 15 October and 11 November. The LROC team scoured the surrounding area in these new mosaics and found the impact site (70.8810°S, 22.7840°E, 834 m elevation) and associated debris field. The November mosaic had the best pixel scale (0.7 meter) and lighting conditions (72° incidence angle).

The debris first located by Shanmuga is about 750 meters northwest of the main crash site and was a single bright pixel identification in that first mosaic (1.3 meter pixels, 84° incidence angle). The November mosaic shows best the impact crater, ray and extensive debris field. The three largest pieces of debris are each about 2×2 pixels and cast a one pixel shadow.

No word yet on what this new information reveals about Vikram’s failure.

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India confirms details of Vikram’s crash on Moon

8:52 am

India’s government has finally officially admitted that its Vikram lunar lander crashed in September.

In a written answer to a question posed to the Department of Space in Lok Sabha, Minister of State in the Prime Minister’s Office (PMO) Jitendra Singh said the “reduction in velocity” of the Vikram lander during the final phase of its descent on the moon’s surface “was more than the designed value”. As a result, Vikram “hard-landed” on the moon “within 500 metres of the designated landing site”, he said.

…“The first phase of descent was performed nominally from an altitude of 30 km to 7.4 km above the moon surface. The velocity was reduced from 1,683 m/s to 146 m/s. During the second phase of descent, the reduction in velocity was more than the designed value. Due to this deviation, the initial conditions at the start of the fine braking phase (final phase below 7.4 km altitude) were beyond the designed parameters. As a result, Vikram hard-landed within 500 m of the designated landing site,” the minister said in a written answer in the Lok Sabha.

Except for the detail that they think Vikram landed within 500 meters of its planned landing site, this answer really doesn’t tell us much new. It was very obvious during the landing that the spacecraft was traveling too fast as it began its final braking phase, and that it then descended much too fast thereafter.

In fact, the couched language and the unwillingness so far of ISRO, India’s space agency, to provide a detailed report on the failure does not reflect well on them. This kind of cutting edge engineering requires a hard kind of intellectual honesty. They have so far not shown that kind of honesty in their response to this failure.

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LRO’s 2nd attempt to find Vikram comes up empty

9:25 am

In their second attempt to find India’s failed lunar lander Vikram, the science team of Lunar Reconnaissance Orbiter (LRO) were unsuccessful in spotting it.

A project scientist of Nasa’s LRO mission confirmed that the space agency’s second attempt to locate Vikram had come up empty. “The Lunar Reconnaissance Orbiter imaged the area of the targeted Chandrayaan-2 Vikram landing site on October 14 but did not observe any evidence of the lander,” Noah Edward Petro, the project scientist told news agency PTI.

Petro explained that Nasa compared the images shot by the LRO on October 14 with an image of the same area before Vikram’s landing. Nasa used a technique that would help it spot any signs of impact on the lunar surface indicating Vikram’s possible location. However, the images revealed nothing.

“It is possible that Vikram is located in a shadow or outside of the search area. Because of the low latitude, approximately 70 degrees south, the area is never completely free of shadows,” John Keller, deputy project scientist of Nasa’s LRO mission, explained while speaking to news agency PTI.

Based on the data obtained during the landing attempt, it appeared that Vikram should have crashed within a relatively small target area. That they haven’t seen it yet suggests that it landed within a shadowed area that will take time for the Sun to reach, if ever, or that it is farther away that expected, which implies that during landing much more went wrong than presently believed.

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LRO scientists release image of Vikram landing site

10:28 am

Overview of Vikram landing area
Click for full image.

The Lunar Reconnaissance Orbiter (LRO) science team yesterday released their high resolution image taken of the area where it is believed India’s lunar lander Vikram crashed.

The image to the right is not that image, but an oblique overview showing where that landing region is, the center of which is indicated by the white cross. Vikram was aiming for this flat region between the Simpelius N and Manzinus C craters.

In releasing the image, the scientists explained what they thought were the reasons they have so far failed to find Vikram.

We note that it was dusk when the landing area was imaged and thus large shadows covered much of the terrain, perhaps the Vikram lander is hiding in a shadow. The lighting will be favorable when LRO passes over the site in October and LROC will attempt to image the lander at that time.

You can explore the actual image at the link. It is quite large, though their viewer there allows you to zoom in and move about, inspecting each grid area very closely. As they note, there are a lot of shadowed areas.

LRO’s high resolution camera can see objects as small as Vikram, even if broke up somewhat on landing. The key for discovery will be timing. LRO will have to pass over at a time when the lander is not in shadow.

UPDATE: Below the fold is a side-by-side comparison of this region, with mid-day on the left and the dusk LRO image on the right, created by Rex Ridenoure of Ecliptic Enterprises.and graciously provided to me.
» Read more

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