Astro 1500 Exam review - Exam 1

If you double the diameter of a telescope, by how much does the resolving power increase?

• 2 times as powerful

• 1/2 times as powerful

• 1/4 times as powerful

• 4 times as powerful

Answer explanation

The resolving power would double! The angular resolution would get smaller, which means the resolving power is going up.

Tags

CCSS.8.EE.C.7B

Everything else remaining the same, if you double a star's temperature, the luminosity increases by __ times.

• 4

• 8

• 16

• 32

Answer explanation

The equation for luminosity depends on T^4, so if T increases a factor of 2, Luminosity increases by (2)^4 = 16 times more

Which one of these is a DISADVANTAGE of a space-based telescope?

• Some parts of the EM spectrum are inaccessible

• It is cheap to get up there

• It is nearly impossible to repair

• Jupiter can block the light

Answer explanation

Other disadvantages include the price, the limited data transfer rate, and limited aperture size

Again, you double the diameter of the telescope. By how much does the light gathering power increase?

• 2 times as powerful

• 4 times as powerful

• 1/2 times as powerful

• 1/4 times as powerful

Answer explanation

Because the equation has R^2, the brightness power will increase 4 times as much

Tags

CCSS.7.G.B.4

Earth's elliptical orbit around the sun explains which of these phenomena?

• Some seasons are warmer than others

• The sun is higher in the sky during some seasons

• 
  Some seasons are slightly shorter than others

• None of these phenomena has anything to do with the Earth's elliptical orbit

Answer explanation

Earth's elliptical orbit means in spends more time at certain positions around the sun, meaning whatever season it is at that time is ever so slightly longer.

Tags

NGSS.MS-ESS1-1

Which of these powers of a telescope matters the least for astronomy purposes?

• Light Gathering Power

• Resolving Power

• Magnification Power

• Cost

Answer explanation

Magnification power doesn't really mean much for astronomy. Making something bigger doesn't correlate to making it clearer (better resolved)

Which of these should we NOT see in a geocentric model that we should see in a heliocentric one?

• Retrograde planetary motion

• The planet Neptune

• Parallax of stars

• Solar eclipses

Answer explanation

There would be no parallax in a geocentric model, because the earth is not moving.

Tags

NGSS.HS-ESS1-4

Why are all major telescopes reflecting telescopes? (Not refracting)

• The weight of lens can cause refracting telescopes to warp

• It's cheaper to build a larger telescope

• Easier to manufacture

• All of the above

Answer explanation

Reflecting telescope are just easier to use for astronomy, though many small, cheaper, personal telescopes are refracting

What is the Copernican Revolution?

• An attempt by Copernicus to overthrow the Polish government

• The transition from a geocentric model to a heliocentric model

• The transition to choosing the simplest explanation as the most likely

• The transition from using thought and intuition to acquire knowledge to instead using empirical evidence

Answer explanation

Copernicus backed up his findings with evidence and fact, rather than trying to think really hard about it like the greeks did

Let’s say that you build your own radio interferometer consisting of two dishes. You move the dishes further apart. In doing so, which of the following is true about resolving power and light gathering power?

• Both the resolving power and the light gathering power stays the same.

• The resolving power remains the same, while the light gathering power becomes better.

• Both the resolving power and the light gathering power become better.

• The light gathering power remains the same, while the resolving power becomes better.

Answer explanation

The light gathering power is determined by the diameter of the dish, whereas the resolving power is by the separation between the dishes (i.e. baselines).

Tags

NGSS.HS-PS4-1

NGSS.HS-PS4-5