Worksheet: The Quest for Extraterrestrial Life | Class 7 English Alive PDF Download

Multiple Choice Questions (MCQs) with Explanations

Q1: What was the main purpose of the Ohio State University Radio Observatory's Big Ear radio telescope?

(a) To monitor weather patterns on Earth.

(b) To search for extraterrestrial intelligence.

(c) To study the Earth's atmosphere.

(d) To observe terrestrial radio frequencies.

Ans: (b) To search for extraterrestrial intelligence.

Explanation: The Big Ear radio telescope was primarily utilized to search for extraterrestrial intelligence, focusing on detecting any unusual or artificially generated radio signals that might suggest the presence of intelligent life beyond Earth.

Q2: What is the significance of the 'Wow! Signal'?

(a) It confirmed the existence of extraterrestrial life.

(b) It was a repeated signal from another galaxy.

(c) It is considered the best candidate for a signal from extraterrestrial intelligence.

(d) It led to immediate contact with an alien civilization.

Ans: (c) It is considered the best candidate for a signal from extraterrestrial intelligence.

Explanation: The 'Wow! Signal' is significant because it remains one of the strongest candidates for a signal from extraterrestrial intelligence. Detected in 1977, this signal's duration and characteristics suggested it was not a typical natural or man-made interference, yet it has not been observed again.

Q3: Which project aims to cover ten times more sky area in search of alien communication?

(a) The Voyager Project

(b) The Apollo Missions

(c) The Breakthrough Listen Project

(d) The Hubble Telescope Program

Ans: (c) The Breakthrough Listen Project

Explanation: The Breakthrough Listen Project is a large-scale initiative funded to expand the search for extraterrestrial communications. It plans to scan ten times more sky area than previous efforts, significantly increasing the chances of detecting alien signals.

Q4: What does the Drake Equation estimate?

(a) The age of the universe

(b) The number of intelligent alien civilizations in our galaxy

(c) The distance to the nearest star

(d) The size of the Milky Way

Ans: (b) The number of intelligent alien civilizations in our galaxy

Explanation: The Drake Equation is used to estimate the number of civilizations in the Milky Way galaxy with which we might be able to communicate. It considers factors like the rate of star formation, the fraction of those stars with planets, and the likelihood of life developing on those planets.

Q5: What was the outcome of the signal observed by the Parkes radio telescope in 2019?

(a) It was confirmed as a signal from Proxima Centauri.

(b) It was likely noise or interference from Earth.

(c) It proved the existence of artificial broadcasts from space.

(d) It was identified as a natural radio emission.

Ans: (b) It was likely noise or interference from Earth.

Explanation: The signal observed by the Parkes radio telescope had characteristics that initially seemed unusual, but further analysis led researchers to conclude that it was likely caused by interference from Earth, rather than being an extraterrestrial communication.

Fill in the Blanks

Q1: Serious scientific efforts to search for extraterrestrial life began with the advent of __________ technology.

Ans: radio

Q2: SETI stands for the __________.

Ans: Search for Extraterrestrial Intelligence.

Q3: The signal detected by the Big Ear telescope in 1977 is known as the __________ Signal.

Ans: Wow

Q4: Frank Drake developed an equation to estimate the potential number of intelligent alien civilizations, known as __________ Equation.

Ans: Drake's

Q5: The __________ was started in 2015 with funding of $100 million to search for alien communication.

Ans: Breakthrough Listen Project

True/False Questions

Q1: The SETI Institute was founded by Carl Sagan and Jill Tarter in 1984.

Ans: True

Q2: The 'Wow! Signal' was detected multiple times after its initial observation.

Ans: False

Q3: The Breakthrough Listen Project plans to cover only a small part of the sky.

Ans: False

Q4: Mars could have been habitable in the past. 

Ans: True

Q5: All signals detected by SETI have been confirmed as extraterrestrial.

Ans: False

Match the Column

Ans:  A-2, B-3, C-4, D-1

Explanation

A-2: SETI focuses on searching for extraterrestrial intelligence.

B-3: Drake Equation estimates the potential number of communicable civilizations in the galaxy.

C-4: Mars Sample Return is about bringing Martian samples back to Earth for analysis.

D-1: Active SETI involves broadcasting messages to space, hoping for a response from alien civilizations.