"In contrast to optical telescopes, which capture the reflected light from the Sun, the new ALMA images show the actual millimeter-wavelength light emitted by the asteroid," said Todd Hunter, an astronomer with the National Radio Astronomy Observatory (NRAO) in Charlottesville, Va., according to a press release. The paper detailing the findings has been accepted for publication in the Astrophysical Journal, Letters.
Juno's next close approach to Earth will be in November 2018. Juno will actually be much closer than it was in 2014, so ALMA will be able to double its resolution.
"This new observation clearly demonstrates that ALMA will be a very powerful tool for studying asteroids," said NRAO astronomer Arielle Moullet, according to the press release. "At its highest resolution, ALMA is powerful enough to resolve the surface of many asteroids."
