''Pragyan'' (from ) is a

lunar rover A lunar rover or Moon rover is a space exploration Rover (space exploration), vehicle designed to move across the surface of the Moon. The Apollo program's Lunar Roving Vehicle was driven on the Moon by members of three American crews, Apollo 15, ...

that forms part of

Chandrayaan-3 Chandrayaan-3 ( ) is the third mission in the Chandrayaan programme, a series of Exploration of the Moon, lunar-exploration missions developed by the ISRO, Indian Space Research Organisation (ISRO). The mission consists of a Chandrayaan-2#Vikra ...

, a lunar mission developed by the

Indian Space Research Organisation The Indian Space Research Organisation (ISRO ) is India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), ...

(ISRO). A previous iteration of the rover, also named Pragyan, was launched as part of

Chandrayaan-2 Chandrayaan-2 (; from Sanskrit: , "Moon" and , "craft, vehicle") is the second lunar exploration mission developed by the Indian Space Research Organisation (ISRO) after Chandrayaan-1. It consists of a lunar orbiter, the ''Vikram'' lunar l ...

on 22 July 2019 and was destroyed with its lander, '' Vikram'', when it crashed on the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

on 6 September.Vikram lander located on lunar surface, wasn't a soft landing: Isro.
''Times of India''. 8 September 2019. Chandrayaan-3 launched on 14 July 2023, carrying new versions of ''Vikram'' and ''Pragyan'', which successfully landed near the

lunar south pole The lunar south pole is the southernmost point on the Moon. It is of interest to scientists because of the lunar water, occurrence of water ice in Crater of eternal darkness, permanently shadowed areas around it. The lunar south pole region fea ...

on 23 August 2023.

Overview

''Pragyan'' has a mass of about and dimensions of , with a power output of 50

watt The watt (symbol: W) is the unit of Power (physics), power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantification (science), quantify the rate of Work ...

s. It is designed to operate on solar power. The rover moves on six wheels and is intended to traverse on the lunar surface at the rate of per second, performing on-site analysis and sending the data to its lander for relay back to the Earth. For navigation, the rover is equipped with: * Stereoscopic camera-based 3D vision: two 1-

megapixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a Raster graphics, raster image, or the smallest addressable element in a dot matrix display device. In most digital display devices, p ...

monochromatic A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, mon ...

NAVCAMs in front of the rover to provide the ground control team a 3D view of the surrounding terrain, and help in path-planning by generating a

digital elevation model A digital elevation model (DEM) or digital surface model (DSM) is a 3D computer graphics representation of elevation data to represent terrain or overlaying objects, commonly of a planet, Natural satellite, moon, or asteroid. A "global DEM" refer ...

of the terrain.

IIT Kanpur The Indian Institute of Technology Kanpur (IIT- Kanpur or IIT-K) is a public institute of technology located in Kanpur, Uttar Pradesh, India. As an Indian Institute of Technology (IIT), it was declared an Institute of National Importance by th ...

contributed to the development of the subsystems for light-based map generation and motion planning for the rover. *Control and motor dynamics: the rover design has a rocker-bogie suspension system and six wheels, each driven by independent

brushless DC electric motor A brushless DC electric motor (BLDC), also known as an electronically commutated motor, is a synchronous motor using a direct current (DC) electric power supply. It uses an electronic controller to switch DC currents to the motor windings, p ...

s. Steering is accomplished by differential speed of the wheels or skid steering. The expected operating time of the rover is one lunar day or around 14 Earth days, as its electronics are not designed to endure the frigid lunar night. Its power system has a solar-powered sleep and wake-up cycle, which could result in a longer operation time than planned.

History

was launched aboard an

LVM3 The Launch Vehicle Mark-3 or LVM3 (previously referred as the Geosynchronous Satellite Launch Vehicle Mark III or GSLV Mk III) is a Multistage rocket, three-stage medium-lift launch vehicle developed by the ISRO, Indian Space Research Organisati ...

-M4 rocket on 14 July 2023, at 09:05 UTC from

Satish Dhawan Space Centre Satish Dhawan Space Centre – SDSC (formerly Sriharikota Range – SHAR) is the primary spaceport of the Indian Space Research Organisation (ISRO), located in Sriharikota, Tirupati district, Andhra Pradesh. The spaceport is located on an isl ...

Second Launch Pad in

Sriharikota Sriharikota () is a barrier island off the Bay of Bengal coast located in the Shar Project settlement of Tirupati district in Andhra Pradesh, India. It houses the Satish Dhawan Space Centre, one of the two satellite launch centres in India (the ...

Andhra Pradesh Andhra Pradesh (ISO 15919, ISO: , , AP) is a States and union territories of India, state on the East Coast of India, east coast of southern India. It is the List of states and union territories of India by area, seventh-largest state and th ...

, India. On 23 August 2023, as the lander approached the low point of its orbit, its four engines fired as a braking manoeuvre at above the Moon's surface. After 11.5 minutes, the lander was 7.2 km (4.5 miles) above the surface; it maintained this altitude for about 10 seconds, then stabilized itself using eight smaller thrusters and rotated from a horizontal to a vertical position while continuing its descent. It then used two of its four engines to slow its descent to roughly ; it hovered there for about 30 seconds and located an optimal landing spot before continuing downward and touching down at 12:32

UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communica ...

. After reaching the Moon's south pole, Chandrayaan-3 deployed the rover to explore the cratered surface, harnessed integrated cameras to send back videos of its environment, and started working on the research objectives planned for a two-week exploration of the Moon. The first video of the rover, posted on 25 August 2023, showed it leaving the Vikram lander on a ramp and driving onto the Moon. ISRO posted the video in a thread on

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that also included footage from the lander approaching its landing site and kicking up dust as it touched down on the surface. ISRO wrote afterwards that the rover's two scientific instruments had been turned on and that it had moved eight meters. On 26 August, the ISRO posted a new video, shot from the lander, of the rover's drive away, moving almost out of the lander's sight. On 27 August, it published two pictures after the rover encountered a large

crater A crater is a landform consisting of a hole or depression (geology), depression on a planetary surface, usually caused either by an object hitting the surface, or by geological activity on the planet. A crater has classically been described ...

positioned three metres ahead of its location. However, the rover safely headed on a new path afterwards. Later on 30 August, at 7:35 am, the rover took a picture of the Vikram lander, showing its two payloads, Chaste and ILSA, had deployed. Another image was captured at 11:04 the same day, from a distance of 15m. On September 2, the rover finished all assignments and entered into a sleep mode in preparation for wake up on September 22, however, it was not expected to continue working. Its battery was fully charged when it went into hibernation. However, after more than two weeks, both the rover and its lander's reactivations were delayed to the 23rd for unspecified reasons. As of 28 September 2023, the rover still had not woken and no updates have been provided by ISRO since. The Pragyan rover is presumed to be dead.

References

{{Orbital launches in 2023 Lunar rovers Missions to the Moon Indian lunar exploration programme LQ30 quadrangle ISRO space probes Spacecraft launched by LVM3 rockets Spacecraft that impacted the Moon 2023 on the Moon Space probes launched in 2023 Spacecraft launched by India in 2023

Overview

History

See also

References