Astronomy in-class activity: SETI and BETI

Astronomy 210 In-class activity 24 v.13.06.11, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to discuss how messages are anticoded, and experience practical issues with incommensurability barrier by attempting to analyze content in a fictitious message from an extraterrestrial advanced technological civilization.

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).


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



This is a truncated version of a much longer in-class activity which also involves counting systems and arithmetic operations used in anticoded messages.

Astronomy clicker question: alien math and the incommensurability problem

Astronomy 10, Spring Semester 2008
Cuesta College, San Luis Obispo, CA

Astronomy 10 learning goal F.3

Students were asked the following clicker question (Classroom Performance System, einstruction.com) near the end of their learning cycle (and just after an in-class activity on BETI).

[0.3 points.] What is the answer to the anticoded message shown above?
(A) 9.
(B) 23.
(C) 25.
(D) 120.

Correct answer: (B)

This is based on the octal counting system and mathematical operators defined in the presumptive Arcturus Project alien message.

The inner curved brackets represent the multiplication operator acting on 3 and 5, and the outer straight brackets represent the next order addition operator acting on 8 and 15, resulting in 23, as demonstrated in the previous in-class activity on BETI.

Student responses
Section 4160
(A) : 2 students
(B) : 5 students
(C) : 9 students
(D) : 13 students

Section 5166
(A) : 5 students
(B) : 30 students
(C) : 2 students
(D) : 8 students

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.