Astronomy

Which of these American astronomers discovered Pluto in 1930?

• Galileo Galilei

• Clyde Tombaugh

• Edwin Hubble

• Harlow Shapley

Answer explanation

Clyde Tombaugh is the American astronomer who discovered Pluto in 1930. Galileo Galilei lived in the 16th-17th centuries, Edwin Hubble is known for his work on galaxies, and Harlow Shapley studied the Milky Way.

What is the name of the first artificial satellite launched into space in 1957?

• Vostok 1

• Sputnik 1

• Explorer 1

• Apollo 11

Answer explanation

The first artificial satellite launched into space in 1957 was Sputnik 1. It marked a significant milestone in the Space Race, while Vostok 1 was the first crewed spacecraft, Explorer 1 was launched later, and Apollo 11 was a lunar mission.

What is the name of the galaxy that is closest to the Milky Way?

• Andromeda Galaxy

• Triangulum Galaxy

• Whirlpool Galaxy

• Sombrero Galaxy

Answer explanation

The Andromeda Galaxy is the closest galaxy to the Milky Way, located about 2.537 million light-years away. It is larger than the Milky Way and is on a collision course with it, making it a significant object of study in astronomy.

What is the name of the first human to travel into space?

• Yuri Gagarin

• Neil Armstrong

• Buzz Aldrin

• John Glenn

Answer explanation

Yuri Gagarin was the first human to travel into space on April 12, 1961, aboard the Vostok 1 spacecraft, making him a significant figure in space exploration history.

Scientists believe the Crab nebula is the remains of:

• • [A] a black hole
    

• • [B] a star which suffered a supernova explosion

• • [C] a galaxy

Answer explanation

The Crab Nebula is the remnant of a star that exploded in a supernova, which is supported by historical records and observations. It is not a black hole or a galaxy, making option [B] the correct choice.

We see flashes from the neutron star when

• it is a red giant expanding in size

• • there is a lunar eclipse

• • one of the magnetic poles is pointed towards the Earth

• it is a white dwarf cooling down

Answer explanation

We see flashes from a neutron star when one of its magnetic poles is pointed towards the Earth, causing the emitted radiation to be directed at us, similar to a lighthouse effect.

X-ray emission from the Crab nebula is the result of

• high-energy particles interacting with gas and dust

• infrared radiation from nearby planets

• radio waves from distant galaxies

• low-energy particles colliding with stars

Answer explanation

X-ray emission from the Crab nebula is primarily due to high-energy particles interacting with gas and dust, which produces the intense radiation observed. Other options do not accurately describe the source of X-ray emissions.

What phenomenon occurs when a star exhausts its nuclear fuel and collapses under its own gravity?

• Supernova

• Black hole

• Neutron star

• White dwarf

Answer explanation

When a star exhausts its nuclear fuel, it can no longer support itself against gravity, leading to a collapse. This collapse can trigger a supernova, an explosive event marking the end of the star's life.

The Crab nebula can be viewed using

• X-ray astronomy

• Radio astronomy

• Ultraviolet astronomy

• all of the above

Answer explanation

The Crab Nebula emits radiation across multiple wavelengths, including X-ray, radio, and ultraviolet. Therefore, it can be observed using all of these astronomical techniques, making 'all of the above' the correct choice.

What type of galaxy is our Milky Way?

• Elliptical

• Spiral

• Irregular

• Round

Answer explanation

The Milky Way is classified as a spiral galaxy due to its distinct spiral arms that extend from the center. This structure is characteristic of spiral galaxies, making 'Spiral' the correct answer.