Space exploration, Exoplanets & life beyond Earth

Question 1

How old is the universe?

Answer 1

Approximately 13.7 billion years (about 3 times the age of the Earth).

Question 2

How old is the Earth?

Answer 2

Approximately 4.5 billion years old.

Question 3

When was the first exoplanet discovered?

Answer 3

In 1995 the first planet outside of our solar system was discovered i.e. “exoplanet”

Question 4

How much is the UK Space Industry worth?

Answer 4

Space industry in UK is worth £7bn and has increased c10% during the recession.

Question 5

How many exoplanets are currently known?

Answer 5

Over 1500 are known about.

800 found in 2014 alone (to date) using the Transiting Technique.

Question 6

How are exoplanets found?

Answer 6

Direct Imaging
Astrometry
Transit Technique
Doppler Shift
Gravitational micro-lensing
Disk features
Timing (pulsars)

Question 7

What is Direct Imaging?

Answer 7

Tricky but by blocking out the starlight around the star you will be able to see any planets orbiting. Only enables us to see exoplanets that are orbiting a long way away from its parent star.

Question 8

What is Astrometry?

Answer 8

Look for the parent star “wobbling” around a barycentre. If there is a large wobble this indicates the presence of an orbiting planet.

Question 9

What is Transit Technique?

Answer 9

As planet moves infront of the star it will cause a dip in the brightness of the star. You can only see planets that are orbiting the star edge on (i.e. not from above or below).

Question 10

What is Doppler Shift?

Answer 10

‘Speed guns’ use this technique to measure speed of passing cars. The doppler shift measures the colour change as the object moves towards and then away from us i.e. it tells you how much the star is wobbling and if it wobbles there’s an object orbiting it.

Question 11

What is Gravitational Micro-lensing?

Answer 11

Optical illusion creates visual copies.

Question 12

What disk features are looked for when searching for exoplanets?

Answer 12

Disk of gas around a star and the features within e.g. planet forming around the star Vega.

Question 13

What timing features are looked for when searching for exoplanets?

Answer 13

Timing (pulsars) = slight change in rotation this may be caused by a planet.

Question 14

What is the Habitable Zone?

Answer 14

Indicates where water could exist (c48 planets found are in habitable zone).

This varies depending on the size & heat of the sun it orbits.

Question 15

What is a parsec?

Answer 15

3 Light Years.

Question 16

What type of star has more planets?

Answer 16

Young stars because they are richer in heavier elements.

Question 17

What bodies in the solar system are candidates for life?

Answer 17

Mars - potentially had life in past.
Europa
Titan

Question 18

What is the Drake Equation?

Answer 18

The Drake equation is a probabilistic argument used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy.

Currently estimated at 42!

Question 19

How long has there been life on Earth?

Answer 19

Approximately 100 million years.

Question 20

How are we searching for ET?

Answer 20

Arecibo Observatory, Puerto Rico.

SETI@home.

Question 21

What is the Wow! Signal?

Answer 21

In 1977 the Big Ear radio telescope picked up a transmission.

The Wow! signal fitted the profile of an alien transmission.

Other explanations have been ruled out. Transmitters on Earth can’t use the same frequency, and the signal was too narrow to come from natural sources.

Interstellar scintillation, the audio equivalent of a star twinkle, has also been dismissed.