Astronomers have conducted an incredible observational test for a radio telescope on Earth. They used a new radar system to capture glorious high-resolution images of near-Earth space. The target: the Apollo 15 landing site on the Moon.
The Green Bank Telescope in West Virginia was outfitted with a new custom-built transmitter of radio waves. Back in November, researchers sent signals towards the Moon in a proof-of-concept test. What they got back is an incredible picture. The Hadley region on the Moon's near-side is visible with a resolution of 5 meters (16.4 feet).
In particular, the image shows the Hadley C crater, which is 6 kilometers ( 3.7 miles) across, and the sinuous Hadley Rille, a narrow depression that extends for 130 kilometers (80 miles) with an average width of 1.2 kilometers (0.75 miles) and a few hundred meters in depth. It is believed to have been an ancient lava tube, which has over billions of years collapsed.
The observations have delivered some of the best views of the region ever taken from Earth, a phenomenal achievement for Green Bank Observatory (GBO), National Radio Astronomy Observatory (NRAO), and Raytheon Intelligence & Space who conducted the experiment.
“This project opens a whole new range of capabilities for both NRAO and GBO,” Tony Beasley, director of the NRAO and vice president for Radio Astronomy at Associated Universities, Inc. said in a statement. “We’ve participated before in important radar studies of the Solar System, but turning the GBT into a steerable planetary radar transmitter will greatly expand our ability to pursue intriguing new lines of research.”
It works by the radar signals emitted by the Green Bank Telescope hitting the surface of whatever object is being studied, in this case, the Apollo 15 landing site on the Moon. They then reflect back and get observed by the telescopes that are part of the Very Long Baseline Array, a network spread from the US Virgin Islands to the continental United States, and all the way to Hawaii.
The incredible test is the achievement of a two-year effort to create such a radar, but it is also currently just a proof of concept. Researchers see the current transmitter as a stepping stone to design something more powerful. Something that can be used to study far beyond the Moon.
“The planned system will be a leap forward in radar science, allowing access to never before seen features of the Solar System from right here on Earth,” explained Karen O’Neil, GBO site director.
The new transmitter is expected to be capable of capturing and providing detailed observations of small objects passing near Earth as well as the moons orbing other planets in the Solar System. If the finalized plan comes to fruition radar signals could allow us to study objects as far as the orbit of Neptune from Earth.