Astro 1010 Exam 4 Study Guide and
Actual Answers 2025 Update.
The 23h 56m length of the sidereal day is determined by which of these? - Answer The time
between each crossing of the celestial meridian for a star.
If you were to travel south of the equator to Chile, which of these changes would you notice? -
Answer The season of the year would be opposite the season in the northern hemisphere.
Why is it cold in June at the North Pole? - Answer The Sun is low in the sky all day.
Suppose the year of the seasons had 365.50 days. What would be a good leap year pattern? -
Answer 1 extra day every 2 years.
The Gregorian calendar, first adopted in the 1580s, made two changes to the Julian calendar.
One change was to reset the date to erase the old error. What was the result of the other
change? - Answer We now have 97 leap years in a 400-year period.
Ptolemy's concept had planets orbiting the Earth in paths that were combinations of circles.
Which is false? - Answer It was proven wrong within a few decades.
With the Copernican model of planetary motion, what is really happening when we observe the
retrograde (backward) motion of Mars against the background of stars? - Answer Mars is
being overtaken and passed by the faster moving Earth.
Failing to see any annual parallax shift of nearby objects against the distant background, Tycho
concluded what? - Answer The Earth is not moving around the Sun.
Suppose a planet orbits the Sun in 5 years. What is its approximate distance from the Sun? -
Answer 3 AU
The eccentricity of a planetary orbit describes what property of the orbit? - Answer Its shape.
Newton found the force responsible for the elliptical orbits of planets. What was the direction
, In hydrogen, an electron changing from the fourth to the second orbital energy level would
account for what spectral line? - Answer An emission line at a visible wavelength.
Which best describes the wavelengths of radiation coming from astronomical objects if the
telescopes are on the Earth's surface? - Answer Visible wavelengths (400-700 nm) and radio
wavelengths greater than 1 mm.
Light from an astronomical object is received by six telescopes in the CHARA array. In what
order do the following come into play after that? - Answer Light pipes, moving mirror carts,
interference pattern.
A certain planet has a mass 20 times Earth's mass and a volume 80 times Earth's volume. Which
would be a correct conclusion from this data? Compared to Earth... - Answer It is less dense.
Which of these has an atmosphere composed primarily of carbon dioxide along with a surface
pressure which is very low compared to Earth's? - Answer Mars
Which of these has the highest average surface temperature? - Answer Venus
What layer in the Earth's interior is responsible for generating our magnetic field? - Answer
Fluid Outer-Core
Thicker crust and fewer maria characterizes which hemisphere of the Moon? - Answer Far-side
Best description of surface activity on Venus? - Answer Volcanic activity ended ½ billion years
ago, but may continue under the clouds.
Our best estimate of the age of the surface of Venus comes from what data? - Answer Crater
counts.
Description of the surface weather on Venus? - Answer Hot, calm winds, day and night
Not done yet on the surface of Mars? - Answer Microbe-containing rocks returned from Mars
to Earth.
Actual Answers 2025 Update.
The 23h 56m length of the sidereal day is determined by which of these? - Answer The time
between each crossing of the celestial meridian for a star.
If you were to travel south of the equator to Chile, which of these changes would you notice? -
Answer The season of the year would be opposite the season in the northern hemisphere.
Why is it cold in June at the North Pole? - Answer The Sun is low in the sky all day.
Suppose the year of the seasons had 365.50 days. What would be a good leap year pattern? -
Answer 1 extra day every 2 years.
The Gregorian calendar, first adopted in the 1580s, made two changes to the Julian calendar.
One change was to reset the date to erase the old error. What was the result of the other
change? - Answer We now have 97 leap years in a 400-year period.
Ptolemy's concept had planets orbiting the Earth in paths that were combinations of circles.
Which is false? - Answer It was proven wrong within a few decades.
With the Copernican model of planetary motion, what is really happening when we observe the
retrograde (backward) motion of Mars against the background of stars? - Answer Mars is
being overtaken and passed by the faster moving Earth.
Failing to see any annual parallax shift of nearby objects against the distant background, Tycho
concluded what? - Answer The Earth is not moving around the Sun.
Suppose a planet orbits the Sun in 5 years. What is its approximate distance from the Sun? -
Answer 3 AU
The eccentricity of a planetary orbit describes what property of the orbit? - Answer Its shape.
Newton found the force responsible for the elliptical orbits of planets. What was the direction
, In hydrogen, an electron changing from the fourth to the second orbital energy level would
account for what spectral line? - Answer An emission line at a visible wavelength.
Which best describes the wavelengths of radiation coming from astronomical objects if the
telescopes are on the Earth's surface? - Answer Visible wavelengths (400-700 nm) and radio
wavelengths greater than 1 mm.
Light from an astronomical object is received by six telescopes in the CHARA array. In what
order do the following come into play after that? - Answer Light pipes, moving mirror carts,
interference pattern.
A certain planet has a mass 20 times Earth's mass and a volume 80 times Earth's volume. Which
would be a correct conclusion from this data? Compared to Earth... - Answer It is less dense.
Which of these has an atmosphere composed primarily of carbon dioxide along with a surface
pressure which is very low compared to Earth's? - Answer Mars
Which of these has the highest average surface temperature? - Answer Venus
What layer in the Earth's interior is responsible for generating our magnetic field? - Answer
Fluid Outer-Core
Thicker crust and fewer maria characterizes which hemisphere of the Moon? - Answer Far-side
Best description of surface activity on Venus? - Answer Volcanic activity ended ½ billion years
ago, but may continue under the clouds.
Our best estimate of the age of the surface of Venus comes from what data? - Answer Crater
counts.
Description of the surface weather on Venus? - Answer Hot, calm winds, day and night
Not done yet on the surface of Mars? - Answer Microbe-containing rocks returned from Mars
to Earth.
