Dawn missed scheduled communications sessions with NASA's Deep Space Network on Wednesday, Oct. 31, and Thursday, Nov. 1. - Once the management group has ruled out other possible causes of lack of communication, experts came to the conclusion that aboard the station ended the hydrazine fuel, the use of which enables the station to maintain orientation in flight. The "astounding" images collected by Dawn are shedding light on the history and evolution of our solar system, said NASA's science mission chief, Thomas Zurbuchen.
Scientists have known for about a month that Dawn was nearly out of hydrazine, a fuel that kept the spacecraft's antennae oriented toward Earth and helped turn its solar panels to the sun to recharge.
Because of the life-on-Ceres question, NASA made a decision to keep Dawn spinning in orbit rather than sending the probe down to crash onto the dwarf planet's pockmarked surface.
Dawn has travelled 4.3 billion miles (6.9 billion km) since launching in 2007. The probe arrived at Ceres in March 2015, becoming the first spacecraft ever to orbit a dwarf planet, and the first to circle two bodies beyond the Earth-moon system. In 2011, when Dawn arrived at Vesta, the second largest world in the main asteroid belt, the spacecraft became the first to orbit a body in the region between Mars and Jupiter.
Because the mission control center didn't plan the station descent to the surface of Ceres, Dawn will remain in this orbit for at least 20 years, and with 99% probability in 50 years.
'The demands we put on Dawn were tremendous, but it met the challenge every time.
This photo of Ceres and one of its key landmarks, Ahuna Mons, was one of the last views Dawn transmitted before it completed its mission. "It carried humankind on a truly fantastic deep space adventure with stunning discoveries".
Dawn's four science experiments furthered humanity's understanding of planet formation and showed that dwarf planets could once have hosted their own oceans, and may still.
Recall that the National Aeronautics and space USA (NASA) announced the completion of the mission the Kepler telescope that worked in space for nine years and found more than 2.6 thousand planets outside the Solar system. That's intentional, as Ceres has conditions that could be right for life, and engineers want to prevent contact between the spacecraft (and any potential Earth microbes it may carry) and the dwarf planet. "Dawn's data sets will be deeply mined by scientists working on how planets grow and differentiate, and when and where life could have formed in our solar system".
An artist's depiction of the Dawn spacecraft between Ceres (left) and Vesta (right) (not shown to scale).
At Ceres, Dawn discovered evidence for cryovolcanism, an analog to volcanism in which cryovolcanoes spew water and other organics, rather than molten rock. Northrop Grumman in Dulles, Virginia, designed and built the spacecraft.