A Los Angeles man was arrested this week on federal charges alleging he targeted seven women with online threats to publish nude photos unless they provided him with additional explicit pictures.

Richard Gregory Bauer, a former contractor at the NASA Armstrong Flight Research Center in Edwards, was arrested without incident at his Mid-Wilshire home by special agents with NASA’s Office of Inspector General, according to the U.S. Attorney’s Office.

Bauer, 28, faces charges contained in a 14-count indictment returned by a Los Angeles federal grand jury on Aug. 28. The indictment charges Bauer with stalking, unauthorized access to a protected computer, and aggravated identity theft.

The indictment alleges that over the past several years, Bauer, who until recently lived in the High Desert communities of Palmdale and Lancaster, harassed the victims on Facebook and through emails.

In emails to six women — in which he used aliases including “Steve Smith,’’ “John Smith’’ and “Garret’’ — Bauer sent the victims previously obtained nude photos of themselves, claimed to have additional photos, and threatened to post the photos online unless the women sent him new photos in various stages of undress, federal prosecutors allege.

Bauer is also charged with unauthorized access to computers and accounts owned by victims. During the course of the alleged stalking, Bauer, using his true identity, contacted some victims on Facebook and posed a series of questions, purportedly as part of a project he was working on for his “human societies class,’’ the indictment alleges.

Some of the questions included typical questions used to reset online passwords, such as the name of your first pet or the city where your parents met. In other instances, again using his true identity, Bauer allegedly convinced victims to install malware by claiming that he needed their help in testing software he claimed to have written, according to prosecutors.

The malware gave Bauer unauthorized access to the computers, and allowed him, among other things, to capture from the victims’ computers passwords for web sites and email accounts, the indictment alleges.

On at least two instances, Bauer is alleged to have used logins and passwords belonging to victims to log on to their Facebook and Google email accounts.

If convicted of the 14 charges in the indictment, Bauer would face up to 64 years in federal prison, according to the U.S. Attorney’s Office.