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BEYOND SCIENCE?: Aliens Have Landed

In July 1947, an alien spacecraft crash landed in the desert near Roswell, New Mexico. Or did it? Frontiers travels to Roswell to find out. Something happened in the desert 50 years ago, but is there any evidence to prove that aliens visited Earth? Or that the government suppressed information? Or that the alien autopsy "documentary" is for real? This account investigates the pseudoscientific claims that have grown more and more extraordinary.

Curriculum Links
What Really Happened in Roswell?
Activity 1: The Value of Experts
Activity 2: The Drake Equation: Is Anybody Out There?
Activity 3: The Value of Eyewitnesses



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The foundation for the belief that a spaceship visited Roswell, New Mexico, is based on two constructs: First, an alien civilization capable of space travel exists; second, visiting aliens left irrefutable evidence on Earth as proof. The three activities in this file will allow you to explore the veracity of these ideas and evaluate accounts.


As you learn on Frontiers, a videotape of an "alien autopsy" allegedly filmed in 1947 surfaced decades later as "evidence" that aliens crash landed in the desert near Roswell. Reputable scientists deemed this film a hoax. However, beliefs persist that the film and 1947 event are real, and television stations continue to air the film as a "documentary," giving it legitimacy.

How can you use your critical thinking skills to evaluate evidence presented as authentic - whether on film, in print or gathered from eyewitness accounts? One way is by studying the film itself to determine whether it is a hoax. Another way is to consult scientists or other experts who can help analyze the evidence.


Use critical thinking skills to gather and evaluate evidence.

  1. This episode of Frontiers shows a brief clip of the film "Alien Autopsy: Fact or Fiction?" Rent the videotape and watch the film. Then answer the question, "What evidence exists to prove or disprove that this is a real autopsy of an alien?"

  2. You first need to make your own observations. Divide a paper in half lengthwise and write the word "prove" on one side and "disprove" on the other. As you watch the video, write down observations under the appropriate column.

  3. Discuss your observations in small groups or as a class. How might an "expert" help support some of your observations?

  4. If possible, invite a filmmaker, special effects person or a physician to your class to watch the film, if they haven't already seen it, and offer their observations. Consult your school's media specialist for possible contacts in the field.
  1. Can you refine your observations into a question that can be tested? (For example, you might ask: "What medical technology was available in 1947?")

  2. What is the value of calling in experts to help evaluate evidence? Consider the role of expert witnesses in trials.

  3. What kinds of bias might experts bring into their evaluations? Is this good or bad?

  4. How does the ability to create special effects affect our ability to determine what is real and what is fake?


Dr. Frank Drake, president of the SETI (Search for Extraterrestrial Intelligence) Institute developed an equation often cited as suggesting the possibility of alien life capable of contacting us. Even without doing the research involved to determine a numerical answer, what does the theoretical premise of the equation tell you?


Examine the possibility that advanced civilizations exist.


Use the Drake Equation as a point of classroom discussion to answer the questions that follow.

The symbols in this equation represent:

N number of civilizations in the Milky Way with detectable radio emissions
R* rate of formation of stars that might support planets with intelligent life
fp fraction of these stars that have planets
ne number of planets per star system that have basic conditions for life
fl fraction of ne planets where life actually develops
fi fraction of fl planets where intelligent life develops
fc fraction of fi planets where technology advanced enough for exploring space develops
L the length of time the civilizations on the fc planets last

  1. Contact a local astronomer or research the Internet to find values for the terms that make up this equation. What is a good estimate of N based on your research? Find out more about the Drake Equation at the SETI Web site at

  2. Have we discovered any stars with planets (fp)?

  3. Have we discovered any planets that might support life (ne)?

  4. What kind of conditions do you think must exist for intelligent life (fi) to develop?

  5. What might limit the length of time (L) that technological civilizations might last? How is our civilization doing?


Much of the evidence cited for proof of the Roswell incident is based on eyewitness accounts of what people saw 50 years ago, as well as on hearsay - what someone else heard from a supposed eyewitness. By staging an incident and studying the accuracy of eyewitness accounts, you can see how what people actually see and what people remember seeing might vary.


Study the accuracy of eyewitness accounts.

  1. Design and set up a scene in your class for observation by other students. The scene can be anything you want it to be - from an alien encounter to a mock crime. The key is to stage a scene with lots of details to observe.

  2. Bring other students, in small groups, into your room to visit. Tell them they are going to watch a scene from a play your class is writing and you will have them critique the play later in the week.

  3. One week later, have student teams interview the observers individually. Ask the observers to describe, in detail, what they remember about the staged scene.

  4. Have each team report back to class how accurate the observations were.

  5. Repeat the interviews at selected intervals (two weeks, one month) after the staged event.
  1. Would observations be more accurate if you didn't wait a week to interview?

  2. Are some individuals particularly good at making observations? Why?

  3. What do you think would happen if you interviewed witnesses six months after the incident? One year or more?
  1. Some of the evidence from Roswell is based on memories of third parties who were not eyewitnesses. Design a way to study how observations change when retold by someone other than the original observer.

  2. Make your own staged videotape of a "UFO" and see if other students can figure out what it is. How do their accounts differ?

  3. Bring in newspaper reports of UFOs. How would you prove or disprove the claims?

  4. How does our current fascination with aliens compare with stories of other mysterious beings (witches, for example) who have captured our imagination in the past?

  5. What do the studies of false memory suggest to us about recollections of events that took place long ago? See "Creating False Memories" in the September 1997 issue of Scientific American.

  6. If you've seen or read Contact, use the ideas in the book and movie to discuss the possibility of life outside our solar system.


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.