When a baseball pitcher throws a fastball, the speed appears on the jumbotron thanks to the radar. The technology also helps with air traffic control, highway speed traps, and weather forecasts, but it’s not just for Earth. Astronomers have used radar to study the planets and asteroids around us, measure their speed as they circle around the Sun, and image their surface details. The new tool promises to enhance this brand of science by offering more detailed astronomical radar capabilities than ever before. The team behind the pioneering radar system at the Green Bank Telescope in West Virginia unveiled its first results last month at the 241st Annual Meeting of the American Astronomical Society, revealing unprecedented details of the moon and the presence of near-Earth asteroids. detected. The telescope’s new radar system, called Next-Generation Radar (ngRADAR), “produced results that exceeded expectations,” said Flora Paganelli, a project scientist in the Radar Division at the National Radio Astronomical Observatory (NRAO).
Radar systems transmit radio waves that bounce off nearby objects. When the waves return to the detector they arrive at different times depending on the distance traveled. Using that information, scientists can reconstruct images of objects or measure their speed. On Earth, our radar equipment is often hand-held, but scaled-up and more powerful versions (in this case, large radio telescopes) can be used to watch asteroids instead of baseballs, while observing Earth’s You can send waves outside.
The ngRADAR system uses the Green Bank telescope as a giant transmitting antenna. very long baseline sequence radio telescopes spread across the United States, Hawaii and the Virgin Islands as mile-wide receivers. Green Bank has a 100-meter diameter dish (equivalent to a radio telescope mirror), the largest steerable antenna on Earth, and is particularly well suited for this task.
To test the new system, the ngRADAR team turned to the moon to image the Apollo landing site and the prominent Tycho crater. These are “the highest resolution images of the Moon ever taken from a ground-based system,” Paganelli says. They reveal meter-sized features and could be of great interest to lunar scientists.
Patrick Taylor, Head of Radar Division at NRAO and Green Bank Observatory, said: “It will be interesting to see how planetary geologists can make use of this information.”
The team also detected an asteroid five times the moon’s distance using less power than a regular microwave oven. Additionally, the new instrument transmits through the Ku band, higher-frequency radio waves than those used by other planetary radars. “This means that we see [asteroids] Edgard Rivera-Valentín, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory, explains. The ngRADAR project.
Tracking asteroids is a lot of fun for planetary scientists looking for these rock masses for clues to the solar system’s past, and it’s also important for humanity. The best way is to find asteroids early and know their properties such as size and density. “The sooner we know about the risks, the more we know about the object, the better we can handle the situation,” says Taylor.
The ngRADAR system comes online at a particularly critical time for planetary defense and radio astronomy. After the catastrophic collapse of Puerto Rico’s famed Arecibo Observatory, only one active radar astronomical observatory remains. NASA’s Goldstone Solar System Radar is part of a deep space network that communicates with spacecraft throughout the solar system. Putting all of humanity’s eggs in Goldstone’s basket would be a particularly risky move, especially since “Goldstone has experienced a recent 18-month-long failure, resulting in the long-term loss of our vital planetary defense capabilities.” ‘because,’ says planetary scientist Jean-Luc. Margot at the University of California, Los Angeles. The ngRADAR system will help fill the gap left by Arecibo, complementing the existing Goldstone facility and strengthening humanity’s perimeter of defense.
And the first results of ngRADAR are just the beginning. The project team is working on improving the initial design with the expectation that it will be a workhorse in radio astronomy for years to come. Steven Wilkinson, an engineer at his Raytheon Technologies who built the ngRADAR system, said:
The team also plans to capitalize on the capabilities of future expansions of the very large array known as ngVLA, making ngRADAR the most sophisticated planetary radar in history over the next decade. “In this future configuration, the system will surpass Arecibo’s sensitivity and allow detection at longer ranges,” says Margot.
