Credit: ISRO

A nine-second de-orbiting maneuver for Chandrayaan-2 spacecraft was performed successfully today (September 04, 2019) beginning at 0342 hrs India Standard Time (IST) as planned, using the onboard propulsion system.

The completion of this maneuver has placed the Vikram lander into the required orbit for it to commence its descent toward the surface of the Moon.

Credit: ISRO/Inside Outer Space Screengrab

The orbit of the lunar lander is now 22 x 63 miles (35 x 101 kilometers).

Meanwhile, the Chandrayaan-2 orbiter continues to circle the Moon in an orbit of 60 x 78 miles (96 x 125 kilometers).

Both the orbiter and lander are healthy, reports the Indian Space Research Organization (ISRO).

Powered descent

The lander is scheduled to begin its powered descent between 0100 – 0200 hrs IST on September 07, 2019, which is then followed by touchdown of the Vikram lander between 0130 – 0230 hrs IST (between 4 and 5 p.m. U.S. Eastern, Sept. 6).

Chandrayaan-2 landing site in the highland plain between the craters Manzinus C and Simpelius N. Simpelius N crater is about 6 miles (9 kilometers) across.
Source: LROC Quickmap
Credit: Jatan Mehta/Moon Monday


The lander is targeted to plop down near the Moon’s south pole.

Given a successful touchdown by the lander, weighing 3,243 pounds (1,471 kilograms), its onboard Pragyan rover, weighing 60 pounds (27 kilograms), is to roll out onto the lunar surface between 5:30 am to 6:30 am.

The 6-wheeled rover can travel up to 1,640 feet (500 meters) from the landing spot on the Moon.

Credit: ISRO



Onboard the Vikram lander is a Radio Anatomy of Moon Bound Hypersensitive ionosphere and Atmosphere (RAMBHA). This experiment is to measure factors such as ambient electron density/temperature near the lunar surface. Also, this experiment can provide a temporal evolution of lunar plasma density for the first time near the surface under varying solar conditions.

NASA-supplied Laser Retroreflector Array.
Credit: NASA/Goddard Space Flight Center




Chandra’s Surface Thermo-physical Experiment (ChaSTE) is to measure the vertical temperature gradient and thermal conductivity of the lunar surface.

Instrument for Lunar Seismic Activity (ILSA) is a Microelectromechanical systems (MEMS)-based seismometer that can detect minute ground displacement, velocity, or acceleration caused by lunar quakes.

Also onboard the lander is a NASA-supplied Laser Retroreflector Array to understand the dynamics of Earth’s Moon system and also derive clues on the lunar interior.

Credit: ISRO



The rover carries an Alpha Particle X-ray Spectrometer (APXS) to determine the elemental composition of the Moon’s surface near the landing site.

A Laser Induced Breakdown Spectrometer (LIBS) is to identify and determine the abundance of elements near the landing site.

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