WASHINGTON (CNN) -- A former U.S. government scientist who served in sensitive positions on classified aerospace projects was willing to sell "some of our most guarded secrets" a prosecutor alleged Tuesday.
Stewart David Nozette of Chevy Chase, Maryland, was taken into custody Monday by FBI agents.
Stewart David Nozette, 52, who is charged with attempted espionage, appeared in U.S. District Court Tuesday afternoon.
Authorities said in a criminal complaint that Nozette, of Chevy Chase, Maryland, tried to deliver classified information to someone he thought was an Israeli intelligence official, but who was actually an FBI undercover agent.
Assistant U.S. Attorney Anthony Asuncion said Tuesday that evidence will show Nozette disclosed to investigators information that was "top secret, related to our national defense, that would cause exceptionally grave damage to national security" if revealed to a foreign country.
He said the FBI made videotapes of Nozette indicating he was "willing to sell some of our most guarded secrets."
The prosecutor noted that the charges carry a possible life sentence.
Nozette answered in the affirmative when Magistrate Judge Deborah Robinson asked him whether he understood the seriousness of the charges against him. Other than that, Nozette, who was arrested Monday, made no statements at his initial court appearance.
Defense attorney John Kiyonaga did not immediately oppose the government's request to hold his client without bond, and said his client agreed to waive a deadline for a formal detention hearing.
Nozette, who remains in custody, will appear in court again on October 29 for detention and preliminary hearings.
In an affidavit, the FBI sets out the case against Nozette, who received a doctorate in planetary sciences from Massachusetts Institute of Technology.
The FBI document, signed by Special Agent Leslie G. Martell, says that Nozette in January 2009 told a colleague "that if the United States government tried to put him in jail" on an unrelated matter, Nozette would move to Israel or another unidentified foreign country and "tell them everything" he knows.
Nozette had a "top secret" clearance, and served at the White House on the National Space Council for President George H.W. Bush, the affidavit says. Later, from early 2000 to early 2006, he did research and development for the Defense Advanced Research Projects Agency, the Naval Research Laboratory, and NASA's Goddard Space Flight Center, it says.
The document says Nozette also acted as a technical consultant from 1998 until early 2008 "for an aerospace company that was wholly owned by the government of the state of Israel."
The company consulted with Nozette monthly, getting answers to questions, and he received total payments of $225,000, Martell's affidavit says.
In early September, Nozette was contacted by phone by an individual purporting to be an Israeli intelligence officer, but who really was an FBI undercover agent, the document says.
They met in downtown Washington in front of a hotel, and over lunch, Nozette "demonstrated his willingness to work for Israeli intelligence," it says.
The undercover agent engaged in a series of meetings with Nozette, and eventually Nozette allegedly provided "secret" information in a "dead drop" post office box. Some of the information, the affidavit says, was classified as secret.
The criminal complaint does not accuse the government of Israel of any violations of U.S. law.