Ellen Stofan, NASA's chief scientist, has left the space agency for other "adventures." Stofan is believed to have left her post before Christmas last month. Slash Gear reported that Stofan first announced her plan to leave during a National Academies' Space Studies Board symposium in California last December. She admitted that she was leaving in two weeks.

It appears that Ellen Stofan left her post around Dec. 20. NASA confirmed her resignation in an interview posted on Tumblr. In the interview, Stofan was asked what she will miss the most about working with the space agency. She admitted that she will miss the people who continue to push back the frontiers of science and technology in order to achieve great things for the country.

The space agency confirmed that Stofan was "departing for new adventures." She was appointed as NASA's chief scientist in Aug. 2013.There was no reason given for her resignation. There was also no indication on who will take over Stofan's place.

According to Engadget, Stofan revealed that the most exciting endeavor that the space agency is on right now is the search for extraterrestrial life. She played a major role in the development of NASA's strategy for human Mars exploration.

Space.com noted that one of her greatest achievements was in getting NASA to voluntarily request demographic information from scientists who submit grant proposals. She believes that the information can be used to identify and understand any biases in how the grants are awarded.

NASA has played a major role in the scientific breakthroughs of 2016. Olivier Guyon, an associate professor at the University of Arizona, Tucson and a planet-hunting affiliate at NASA, described the discovery of an Earth-like planet as a "game-changer" in the field.

This year, NASA will be sending the OSIRIS-REx spacecraft to its two-year outbound journey to asteroid Bennu. It will pass near Earth's L-4 point, which is gravitationally stable and lies 60 degrees ahead in orbit.