Space station analysis contributes to navigation methods for moon voyages

On its mission to the Moon, NASA’s Orion spacecraft is designed to make use of NASA’s Near Space Network and Deep Space Network to navigate. But if the craft loses communication with the bottom or the Networks, crews can use a backup autonomous navigation system generally known as Optical Navigation (OpNav). This system analyzes pictures of the Moon or Earth taken from the spacecraft to find out its place relative to both of these two our bodies.

An investigation presently underway aboard the International Space Station helps builders of OpNav fine-tune the system to make sure that crews return residence safely. The Moon Imagery investigation makes use of images of the Moon taken from the space station to calibrate the system software program.

“The space station gives us a platform to collect images of the Moon without interference from Earth’s atmosphere,” says principal investigator Steve Lockhart at NASA’s Johnson Space Center in Houston. “We can get pretty decent images from the ground, especially when the Moon is near full and high in the sky. The challenge is getting clear images of the Moon in its very thin phases. Because it is close to the Sun then, the sky is only dark enough to get images when the Moon is close to horizon, and then you are looking through a lot of atmosphere.”

The investigation makes use of two cameras mounted on a plate and offset about 20 levels from one another. The plate is put in within the station’s cupola, a seven-windowed statement module, and the cameras level out one of many home windows that has pure glass for the clearest view. One digicam captures pictures of the celebrities and the opposite takes photographs of specified views of the Moon. Each particular view is offered solely as soon as a month for a brief four-minute window. Software then makes use of algorithms to investigate these pictures and decide the craft’s place in space.

“We know where the space station is at all times and where it was when a particular photo was taken based on the time it was taken,” says Lockhart. “The algorithm tells us where it thinks station is and we can compare that to the actual known location to judge the accuracy of our system.”

The system is automated, he provides. The space station crew merely instructions the digicam to level at Earth or the Moon, whichever is essentially the most appropriate goal on the time, to take a sequence of photographs for an hour or so.

Crew members now have performed 4 runs of the investigation, photographing a whole 29-day cycle of the Moon’s phases.

Images from the latest run in May captured totally different exposures, from very under-exposed to extremely over-exposed. Researchers plan to investigate these pictures to see whether or not they can be utilized to find out vary and bearing from the space station and, from that, a spacecraft’s location, corresponding to Orion’s place between the Moon and Earth.

That run additionally captured a really skinny crescent Moon, one of the difficult circumstances for the system’s image-processing algorithms. The crew can enhance future variations of the algorithm primarily based on how the system handles this difficult Moon stage, considered one of a number of goals for the upcoming Artemis I mission.

During trajectory correction maneuvers, the OpNav digicam mounted on the surface of Orion will take repeated Moon and Earth pictures for about two hours. These a number of pictures ought to guarantee correct measurements of Orion’s location within the occasion the backup navigation system is required. Accurately understanding a spacecraft’s location is crucial to guiding it safely again to re-entry into Earth’s ambiance.

Communications and navigation functionality is without doubt one of the key applied sciences wanted for people to discover farther into space. Orion is NASA’s subsequent technology spacecraft, able to transporting people to low-Earth orbit and past, together with to the Moon. Lockhart says that industrial space exploration corporations even have proven curiosity within the autonomous navigation system.

The Moon Imagery investigation is one instance of how the space station supplies researchers with a platform to put the groundwork for applied sciences and demonstrations that transfer humanity nearer to deep space exploration.