A physicist has argued that fundamental cosmic constraints make visits from alien civilizations to Earth effectively impossible. Factors such as vast interstellar distances, the speed of light as a ...

WASHINGTON (AP) — A polarizing Harvard astronomer known for splashy theories about alien visits has been tapped by the White House to lead a team of outside scientists to study the national security ...

Astrophysicist Benjamin Zuckerman concludes that no alien civilization has passed within 100 light-years of Earth in billions of years, based on the absence of alien probes or strong, continuous ...

Avi Loeb, a Harvard astronomer who has made headlines with his theories about alien encounters, will lead a White House scientific advisory council on UFOs.

WASHINGTON (AP) — A polarizing Harvard astronomer known for splashy theories about alien visits has been tapped by the Trump administration to lead a team of outside scientists to study the national ...