Astronomy in-class activity: SETI and BETI

Astronomy 10 In-class activity 30 v.06.12.15, spring semester 2008
Cuesta College, San Luis Obispo, CA

Astronomy 10 learning goal F.3

Students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to discuss how messages are encoded, and the problems that may arise from the incommensurability barrier.

Start out with going over the original Arecibo message (and presumptive crop circle reply in Chilbolton, England, 2001) in a whole-class discussion. Point out to or ask students about the key features of these messages: counting (binary); height and population of inhabitants; schematic representation of planetary systems and communication devices (radio dishes and supposed crop-crushing apparatus).


Then go over the first two pages of both the Cosmic Call message and the presumptive message received by the Arcturus Project. Note the counting schemes (binary, decimal, octal), and the symbols for equality, inequality, and syntax for basic arithmetic operations (addition, subtraction, multiplication, and division).


With these clues, students then start working in their groups.






Related links:

• The Original Arecibo Message
  Discussion on the meaning of each component.
  
• Chilbolton "Photograms"
  Bird's-eye view and close-up photos of the Chilbolton "reply" to the Arecibo message.
  
• Encounter 2001 Message
  Complete list of all Cosmic Call pages.
  
• The ERSO Arcturus Project
  Fictitious ET message received by "Ed's Radio SETI Observatory."
  
• The Incommensurability Problem
  Excerpted from an article on challenges in creating interstellar messages.