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Astro 1 Exam 2 PSU Questions and Answers
What is the order of the planets with distance from the Sun? - ANSWER ✔✔-Mercury, Venus, Earth,
Mars, Jupiter, Saturn, Uranus, and Neptune.
Which planet has the highest surface temperature? - ANSWER ✔✔-Venus
Which planet has the largest mass? - ANSWER ✔✔-Jupiter
Which planet has the largest tilt of its spin axis? - ANSWER ✔✔-Uranus
Which planet has the largest temperature variations? - ANSWER ✔✔-Mercury
Which planet rotates backwards? - ANSWER ✔✔-Venus
Which planet has polar ice caps? - ANSWER ✔✔-Mars
How many moons does Mercury have? - ANSWER ✔✔-0
How many moons does Venus have? - ANSWER ✔✔-0
How many moons does Mars have? - ANSWER ✔✔-2
Which planets have no atmosphere? - ANSWER ✔✔-Mercury
Which moon has a thick atmosphere in the solar system? - ANSWER ✔✔-Titan
Which 3 factors determine if a planet holds onto an atmosphere? - ANSWER ✔✔-Planet mass, Gas mass,
Gas Tempiture
What is the primary reason why Venus is much hotter than Earth? - ANSWER ✔✔-its dense atmosphere
traps heat in a runaway version of the greenhouse effect that warms Earth.
Created by Grace Amelia © 2025, All Rights Reserved.
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Who discovered Pluto? - ANSWER ✔✔-Clyde Tombaugh in 1930
How was Pluto discovered? - ANSWER ✔✔-Astronomers noticed that the orbits of Neptune and Uranus
were being affected by the gravity of an unknown object in the Solar System.
What is the distance of Pluto from the Sun in AUs? - ANSWER ✔✔-30 to 50 AU
What is pluto's Orbital period? - ANSWER ✔✔-248 years
Which spacecraft visited Pluto? - ANSWER ✔✔-New Horizons
How does the orbit of Pluto compare to the 8 planets? - ANSWER ✔✔-it's highly elliptical and titled
Why isn't Pluto considered a planet? - ANSWER ✔✔-it lacks enough mass and gravity to clear its
neighborhood and is not a moon.
What is the official classification of Pluto now? - ANSWER ✔✔-dwarf planet
What other members are apart of the same class as Pluto? - ANSWER ✔✔-Eris and Ceres, Vesta
What are the 3 regions of the solar system containing asteroids and comets? - ANSWER ✔✔-Asteroid
Belt, Kuiper Belt, Oort Cloud
What are the largest known members of the Asteroid Belt and Kuiper Belt? - ANSWER ✔✔-Ceres,vesta
Pluto, Eris
How many asteroids are visible to the naked eye? - ANSWER ✔✔-1
What are comets and asteroids made of? - ANSWER ✔✔-Ice Rocky material
Which spacecraft has visited Vesta and Ceres? - ANSWER ✔✔-The Dawn spacecraft
what space craft deploy a lander onto a comet? - ANSWER ✔✔-Rosestta
What causes a cloud of gas and dust to collapse to form a star? - ANSWER ✔✔-Gravity
Created by Grace Amelia © 2025, All Rights Reserved.
Astro 1 Exam 2 PSU Questions and Answers
What is the order of the planets with distance from the Sun? - ANSWER ✔✔-Mercury, Venus, Earth,
Mars, Jupiter, Saturn, Uranus, and Neptune.
Which planet has the highest surface temperature? - ANSWER ✔✔-Venus
Which planet has the largest mass? - ANSWER ✔✔-Jupiter
Which planet has the largest tilt of its spin axis? - ANSWER ✔✔-Uranus
Which planet has the largest temperature variations? - ANSWER ✔✔-Mercury
Which planet rotates backwards? - ANSWER ✔✔-Venus
Which planet has polar ice caps? - ANSWER ✔✔-Mars
How many moons does Mercury have? - ANSWER ✔✔-0
How many moons does Venus have? - ANSWER ✔✔-0
How many moons does Mars have? - ANSWER ✔✔-2
Which planets have no atmosphere? - ANSWER ✔✔-Mercury
Which moon has a thick atmosphere in the solar system? - ANSWER ✔✔-Titan
Which 3 factors determine if a planet holds onto an atmosphere? - ANSWER ✔✔-Planet mass, Gas mass,
Gas Tempiture
What is the primary reason why Venus is much hotter than Earth? - ANSWER ✔✔-its dense atmosphere
traps heat in a runaway version of the greenhouse effect that warms Earth.
Created by Grace Amelia © 2025, All Rights Reserved.
, 2|Page
Who discovered Pluto? - ANSWER ✔✔-Clyde Tombaugh in 1930
How was Pluto discovered? - ANSWER ✔✔-Astronomers noticed that the orbits of Neptune and Uranus
were being affected by the gravity of an unknown object in the Solar System.
What is the distance of Pluto from the Sun in AUs? - ANSWER ✔✔-30 to 50 AU
What is pluto's Orbital period? - ANSWER ✔✔-248 years
Which spacecraft visited Pluto? - ANSWER ✔✔-New Horizons
How does the orbit of Pluto compare to the 8 planets? - ANSWER ✔✔-it's highly elliptical and titled
Why isn't Pluto considered a planet? - ANSWER ✔✔-it lacks enough mass and gravity to clear its
neighborhood and is not a moon.
What is the official classification of Pluto now? - ANSWER ✔✔-dwarf planet
What other members are apart of the same class as Pluto? - ANSWER ✔✔-Eris and Ceres, Vesta
What are the 3 regions of the solar system containing asteroids and comets? - ANSWER ✔✔-Asteroid
Belt, Kuiper Belt, Oort Cloud
What are the largest known members of the Asteroid Belt and Kuiper Belt? - ANSWER ✔✔-Ceres,vesta
Pluto, Eris
How many asteroids are visible to the naked eye? - ANSWER ✔✔-1
What are comets and asteroids made of? - ANSWER ✔✔-Ice Rocky material
Which spacecraft has visited Vesta and Ceres? - ANSWER ✔✔-The Dawn spacecraft
what space craft deploy a lander onto a comet? - ANSWER ✔✔-Rosestta
What causes a cloud of gas and dust to collapse to form a star? - ANSWER ✔✔-Gravity
Created by Grace Amelia © 2025, All Rights Reserved.
