The NASA pigmentation experiment on Israeli Lander could help future lunar landings

An Israeli spacecraft is heading for the moon, which is expected to land on April 11 at Mare Serenitatis, in the northern hemisphere of the near-face of the moon. Onboard is an experiment, smaller than a computer mouse, that could achieve precise landings of future robotic landers and humans.

the Beresheet, whose name means "genesis" or "originally" in Hebrew, launched on February 21st. The Explorer is a joint project of the SpaceIL non-profit group and Israel Aerospace Industries. Since takeoff, Beresheet has been performing a methodical series of orbiting maneuvers around the Earth to lunar orbit, and then attempt a landing.

For lunar jump, a network of NASA laser reflectors is composed of eight mirrors consisting of wedges of quartz cubes arranged in a domed aluminum frame. This network is light, hardened by radiation and lives for a long time.

Related: The first Israeli moon Lander Beresheet in pictures

Precision Landing

If Beresheet successfully implanted on the moon on April 11, NASA Moon recognition orbiter (LRO) will eventually use its laser altimeter to emit laser pulses on the reflex reflector. Using this technique, the lunar position of Beresheet can be located within 10 cm (4 inches), said members of the project team.

NASA wants to dot the moon with many retroreflectors in the future. These would serve as permanent "fiduciary marks" on the moonThis means that future ships could use them as reference points for precision landings.

The instrument that NASA has placed on Beresheet, called the NASA Goddard Space Flight Center (LRA) for Lunar Landers, is located on the upper face of the Israeli lander, so it can be seen from above.

(Image: © SpaceIL / Courtesy Xiaoli Sun / GSFC)

Laser beams

The LRA is a passive instrument. It will be used in conjunction with the LRO Lunar Orbiter Altimeteror LOLA. The laser beams of this altimeter strike and are backscattered from the lunar surface. For each laser beam, LOLA measures its flight time or range.

There will be no attempt to place the LRO remote reflector until Beresheet is no longer active on the moon. This ensures that the LRO laser will not damage any sensitive receptors on the Israeli receiver, said David Smith of the Massachusetts Institute of Technology, LOLA Senior Investigator and Emeritus Researcher at NASA Goddard, in the Maryland Greenbelt.

Subsequently, LOLA will attempt to make distance measurements to the landing gear from LRO.

"It is an experiment to determine the feasibility, and it will be possible to continue to perform measurements on the network for an indefinite period, or as long as the LOLA instrument on LRO continues to run, which is approaching 10 years in June 2019, "Smith told Space.com.

Related: Moon's latest moonlight orbital reconnaissance NASA photos

(Image: © SpaceIL / Courtesy Xiaoli Sun / GSFC)

Spot lighting

The laser network was designed and designed by Smith and Xiaoli Sun at NASA Goddard about 15 years ago for NASA Phoenix Mars Lander.

"It was expected that it would work with the laser altimeter that we had on NASA 's Mars Global Surveyor probe.Before the arrival of the lander on Mars, the instrument did not work. was more active, "said Smith. The goal of the Mars and Moon arrays is to try to locate the landing gear position of an orbiting spacecraft equipped with a laser system, he said.

In principle, if you approach the reflector network several times, NASA will be able to determine the location of the undercarriage. But the accuracy of this method is limited by the size of the point illuminated by the laser on the surface, Smith said.

A laser that generates a 5-meter spot on the surface requires very precise laser tracking, Smith said. It will be easier for a broad beam laser to detect the array of reflectors, but knowledge of the location of the network at the surface will be more uncertain, he said.

(Image: © NASA / GSFC)

Lonely lunar laser

"A properly designed telemetry system could solve this problem," Smith said. "LOLA was designed to do altimetry, not to go to a small network of reflectors, but it's the only laser on the moon for the near future."

The images taken by the LRO, top executive, can clearly identify Beresheet's position of Israel on the moon. Thus, the laser reflector network is an experiment to determine how difficult it will be for LRO to perform distance measurements to the undercarriage, Smith said.

"A small group of these small bays placed around a landing site, for example, could help a lander get back to a place at some point," Smith said. "Needing no power, the berries could be used for decades, if not longer."

(Image: © NASA)

Future applications

Smith said that there were also potential applications for these small reflectors on other celestial bodies, such as asteroids. Placing – perhaps dropping – a number of small dies on the surface of a body would allow nearby probes to monitor the rotation and position of the object, as well as determine its shape.

"Since the reflectors could last for decades, the object could be monitored by another spacecraft during subsequent visits and, of course, would help to land on the object if it wishes." Smith added.

Of course, the small size of the reflectors limits the range from which they can be detected. The current laser concepts to be built at NASA, Goddard, could allow measurements to be more than 10,000 kilometers (6,000 miles), Smith said.

"These small reflectors weigh only about 20 grams [0.7 ounces] but could be much bigger and able to be detected from even greater scope, "Smith said. Bigger would mean heavier, and one of the attractions of these small reflectors is that they are of very low mass, so almost any undercarriage can carry them. "

Leonard David has written the forthcoming book "Moon Rush: The New Race in Space", which will be published by National Geographic in May 2019. Longtime writer for Space.com, David made a report about the 39, the space industry for more than five decades. Follow us on twitter @Spacedotcom or Facebook.