What first did Kepler-186f represent in 2014?

First Earth-size planet in another star's habitable zone

How did Kepler detect planets?

By measuring dips in starlight as planets passed in front

By photographing planets directly

Kepler-186f Quiz: The First Earth-Size Habitable Zone Planet

A planet about 1.1 times Earth's size circles a red dwarf some 580 light-years away, and this Kepler-186f quiz explains why its 2014 discovery mattered. Play 10 interactive questions on NASA's Kepler telescope, the transit method, Elisa Quintana's team, the habitable zone, its 130-day year, weak sunlight, Cygnus and NASA's red-grass poster.

Start Kepler-186f Quiz

🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

Record
What first did Kepler-186f represent in 2014?
Telescope
Which space telescope found Kepler-186f?
Method
How did Kepler detect planets?
Leader
Who led the team announcing Kepler-186f?
Star
What kind of star does Kepler-186f orbit?
Distance
Roughly how far away is Kepler-186f?
Year
Roughly how long is a year on Kepler-186f?
Size
How big is Kepler-186f compared with Earth?
Light
How much energy does it receive from its star compared with Earth?
Poster
What did a NASA travel poster jokingly say about Kepler-186f?

Explanations: answer key for all 10 questions

Q1: What first did Kepler-186f represent in 2014?
Answer: First Earth-size planet in another star's habitable zone
Earlier habitable-zone finds were larger.
Q2: Which space telescope found Kepler-186f?
Answer: Kepler
Kepler launched in 2009 to search for transiting planets.
Q3: How did Kepler detect planets?
Answer: By measuring dips in starlight as planets passed in front
This is the transit method.
Q4: Who led the team announcing Kepler-186f?
Answer: Elisa Quintana
She worked at NASA Ames Research Center.
Q5: What kind of star does Kepler-186f orbit?
Answer: A red dwarf
Red dwarfs are smaller and cooler than the Sun.
Q6: Roughly how far away is Kepler-186f?
Answer: About 580 light-years
It lies in the constellation Cygnus.
Q7: Roughly how long is a year on Kepler-186f?
Answer: About 130 days
It orbits at the outer edge of the habitable zone.
Q8: How big is Kepler-186f compared with Earth?
Answer: About 10 percent larger
Its exact mass is unknown.
Q9: How much energy does it receive from its star compared with Earth?
Answer: About a third
Midday might look like Earth's sunset light.
Q10: What did a NASA travel poster jokingly say about Kepler-186f?
Answer: The grass is always redder
Plants there might use red light differently.

Kepler-186f Quiz – An Earth-Size World in the Habitable Zone

In April 2014, a team led by Elisa Quintana at NASA Ames announced Kepler-186f, the first Earth-size planet found in the habitable zone of another star. NASA's Kepler telescope found it by watching for dips in starlight as the planet passed in front of its star.

Kepler-186f is about 10 percent larger than Earth and orbits a red dwarf about 580 light-years away in Cygnus. Its year lasts about 130 days, and it receives about a third of the energy Earth gets from the Sun.

Scientists do not know if it has an atmosphere or water, but its discovery showed Earth-size worlds can exist in habitable zones. NASA's playful poster said the grass is always redder there.

What This Quiz Teaches

Space fans and students will enjoy these questions.

Why it was important
How it was found
What kind of star it orbits
How it compares with Earth
What remains unknown

Did You Know?

Kepler-186 has at least five known planets.
The Kepler mission ended in 2018.
Habitable zone means liquid water could exist.
Red dwarfs are the most common stars.
Kepler found thousands of exoplanets.