Space Science Practice Questions
20 free Space Science practice questions for the Static GK. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Which layer of the Sun is the only part visible to the naked eye during a total solar eclipse?
- A Photosphere
- B Chromosphere
- C Corona
- D Core
Correct answer: Corona
The corona is the outermost layer of the Sun's atmosphere. It is usually hidden by the bright light of the photosphere but becomes visible as a pearly white halo during a total solar eclipse.
What is the primary engine that powers a star, converting hydrogen into helium?
- A Nuclear Fission
- B Nuclear Fusion
- C Combustion
- D Gravitational Collapse
Correct answer: Nuclear Fusion
Nuclear fusion occurs in the core of stars where extreme pressure and temperature cause hydrogen nuclei to fuse into helium. This process releases a massive amount of energy in the form of light and heat.
Which planet in our solar system is known as the 'Morning Star' or 'Evening Star'?
- A Mars
- B Jupiter
- C Venus
- D Saturn
Correct answer: Venus
Venus is the brightest natural object in the night sky after the Moon. Because its orbit is within Earth's, it always appears close to the Sun, visible either just after sunset or just before sunrise.
What is the boundary around a black hole beyond which nothing, not even light, can escape?
- A Singularity
- B Accretion Disk
- C Schwarzschild Radius
- D Event Horizon
Correct answer: Event Horizon
The event horizon is the theoretical 'point of no return' surrounding a black hole. Once an object crosses this boundary, the gravitational pull is so strong that escape is physically impossible.
Which celestial body is the primary cause of tides in Earth's oceans?
- A The Sun
- B An Asteroid
- C Venus
- D The Moon
Correct answer: The Moon
Tides are primarily caused by the gravitational pull of the Moon on Earth's oceans. The Sun also exerts a gravitational force that contributes to tides, but its effect is less than half that of the Moon due to its distance.
What is the name of the first artificial satellite launched into space in 1957?
- A Explorer 1
- B Vostok 1
- C Telstar
- D Sputnik 1
Correct answer: Sputnik 1
Sputnik 1 was launched by the Soviet Union on October 4, 1957. It was a small polished metal sphere with four external radio antennas to broadcast radio pulses.
Which unit of distance is defined as the average distance between the Earth and the Sun?
- A Light-year
- B Parsec
- C Light-minute
- D Astronomical Unit
Correct answer: Astronomical Unit
One Astronomical Unit (AU) is approximately 150 million kilometers (93 million miles). It is a convenient unit for measuring distances within our solar system.
Which planet has the shortest day, completing one full rotation in about 10 hours?
- A Mercury
- B Jupiter
- C Saturn
- D Neptune
Correct answer: Jupiter
Jupiter is the fastest-spinning planet in the solar system. This rapid rotation causes the planet to have an oblate shape, meaning it bulges slightly at the equator.
What is a 'Light-year' a measurement of?
- A Time
- B Speed
- C Brightness
- D Distance
Correct answer: Distance
A light-year is the distance that light travels in a vacuum in one Julian year. It is approximately 9.46 trillion kilometers.
Which dwarf planet is located in the asteroid belt between Mars and Jupiter?
- A Pluto
- B Eris
- C Makemake
- D Ceres
Correct answer: Ceres
Ceres is the largest object in the main asteroid belt. It was the first dwarf planet to be visited by a spacecraft (Dawn) and contains about one-third of the total mass of the asteroid belt.
The 'Big Bang' theory explains the origin of what?
- A The Solar System
- B The Universe
- C The Milky Way
- D Black Holes
Correct answer: The Universe
The Big Bang theory suggests that the universe began as a hot, dense point and has been expanding for approximately 13.8 billion years. It is the prevailing cosmological model for the observable universe.
Which planet is known as the 'Red Planet' due to iron oxide on its surface?
- A Venus
- B Mars
- C Jupiter
- D Mercury
Correct answer: Mars
Mars appears red because its surface is covered in iron oxide, commonly known as rust. This dust is kicked up into the atmosphere, giving the planet a reddish hue even from a distance.
What is the name of the galaxy that is closest to our own Milky Way?
- A Andromeda Galaxy
- B Sombrero Galaxy
- C Whirlpool Galaxy
- D Triangulum Galaxy
Correct answer: Andromeda Galaxy
The Andromeda Galaxy (M31) is a spiral galaxy approximately 2.5 million light-years from Earth. It is the largest galaxy in the Local Group and is visible to the naked eye under dark skies.
Which instrument is used to split light from stars into a spectrum to analyze their chemical composition?
- A Telescope
- B Spectrograph
- C Photometer
- D Interferometer
Correct answer: Spectrograph
A spectrograph breaks down light into its component colors (wavelengths). By studying the absorption lines in a star's spectrum, astronomers can identify the elements present in the star.
What are the vast, dark, basaltic plains on the Moon called?
- A Maria
- B Highlands
- C Craters
- D Rays
Correct answer: Maria
Maria (singular: mare) are large, dark, flat areas on the Moon formed by ancient volcanic eruptions. Early astronomers mistook them for seas, which is why they were named using the Latin word for 'seas'.
Which star is the closest star to Earth after the Sun?
- A Proxima Centauri
- B Sirius
- C Alpha Centauri A
- D Betelgeuse
Correct answer: Proxima Centauri
Proxima Centauri is a small, low-mass red dwarf star located about 4.24 light-years from Earth. It is part of the Alpha Centauri star system.
What determines the color of a star?
- A Its surface temperature
- B Its distance from Earth
- C Its chemical composition
- D Its age
Correct answer: Its surface temperature
A star's color is a direct indicator of its surface temperature; blue stars are the hottest, while red stars are the coolest. This is described by Wien's Displacement Law in physics.
Which planet is famous for its prominent and complex ring system made of ice and rock?
- A Saturn
- B Jupiter
- C Uranus
- D Neptune
Correct answer: Saturn
While all four gas giants have rings, Saturn's are the most extensive and visible. They are composed mostly of water ice particles, ranging in size from dust to large boulders.
What is the phenomenon where a moon passes between a planet and its sun, casting a shadow?
- A Eclipse
- B Solstice
- C Equinox
- D Transition
Correct answer: Eclipse
An eclipse occurs when one celestial body moves into the shadow of another. A solar eclipse happens when the Moon moves between the Sun and Earth, blocking the Sun's light.
Which space telescope was launched in 2021 to succeed the Hubble Space Telescope?
- A Kepler Space Telescope
- B Spitzer Space Telescope
- C James Webb Space Telescope
- D Compton Gamma Ray Observatory
Correct answer: James Webb Space Telescope
The James Webb Space Telescope (JWST) is an infrared observatory designed to solve mysteries in our solar system and look back at the first signals from the early universe. It features a much larger primary mirror than Hubble.