Phil Plait (Grad ’90, ’94) has a simple lesson plan. Known Webwide as “The Bad Astronomer,” he wants to stop bad science, especially the spread of misinformation about all things celestial.

Phil Plait, known Webwide as "The Bad Astronomer," blogs to put a stop to bad science. Image courtesy of

His campaign to right the wrongs against astronomy began in 1998 with the launch of, a lively, humorous site to which he later added a blog. ranked it among the “25 Best Blogs” for 2009.

One of the worst instances of bad science, he says, is the claim that NASA faked the moon landings in the 1960s and 1970s. Plait neatly debunks it in his 2002 book, Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing “Hoax.” He continues to stamp out new outrageous theories, as they crop up, on his Web site.

President of the James Randi Educational Foundation, Plait worked with the Hubble Space Telescope team at NASA in the 1990s and later did public outreach for other NASA-funded missions as a member of the astronomy and physics department at Sonoma State University. He says he got the teaching bug as a doctoral student at UVA. For three years, he ran a nighttime lab for astronomy students, but his favorite experience was when the public was invited to peer through the telescopes at Observatory Hill and Fan Mountain. All the questions put his talents to the test, he says, recalling an 8-year-old and his grandmother who tag-teamed him about black holes.

The conspiracy theory about the moon landings has seen a resurgence, says Plait.

Plait debunks moon landing hoax theories:

In the pictures taken by the Apollo astronauts from the surface of the moon, no stars are visible. Conspiracy theorists say this proves that the whole thing was staged somewhere in the Nevada desert. Without air, the sky is black, so where are the stars?

Photo courtesy of NASA

Answer: The stars are there, but are too faint to be seen. “It has nothing to do with the sky being black or the lack of air, it’s just a matter of exposure time,” Plait explains. Because the lunar landscape is brightly lit by the sun, the film exposure times had to be short—and stars do not produce enough light to show up during a quick exposure.

When the astronauts were assembling the American flag, it waved. A flag wouldn’t wave in a vacuum, so it must have been an errant breeze on the set.

Answer: A flag can wave in a vacuum. In the second instance, the flag is not waving; it just looks that way because of the way it was deployed. The Apollo 11 astronauts could not get the rod to extend completely, consequently the flag was not fully stretched out. In later missions, astronauts didn’t fully extend the rod on purpose because they liked the effect. Adds Plait: “If it was a mistake caused by a breeze on the set where they faked the whole thing, don’t you think the director would have tried for a second take? With all the money going to the hoax, they could afford the film!”

Photo courtesy of NASA

In pictures of the lunar lander, there is no blast crater. A rocket powerful enough to land on the moon should have burned out a huge crater.

Answer: The lander had a throttle, so it slowed before touching down on the moon’s surface. More to the point, a rocket’s exhaust will spread out rapidly in a vacuum. On Earth, air constrains the thrust of a rocket into a narrow column; in a vacuum, the absence of air means that the exhaust dissipates, lowering the pressure; hence no blast crater. Even though the lander was using 3,000 pounds of thrust, it spread out so much that the landing was actually gentle.

Photo courtesy of NASA

When the top half of the lander took off from the moon, there was no flame from the rocket. Since every rocket has a visible flame, the takeoff must have been faked.

Answer: This answer is simple, Plait says. The fuels used by the lander, a mix of hydrazine and an oxidizer called dinitrogen tetroxide, produce no visible flame. When the two chemicals ignite on contact, the result is a transparent flame.


This article appeared as part of the article “Space Odyssey: Alumni Who Have ‘The Right Stuff.’” Read about alumni missions in space and the future of NASA.