USU PHYS 3100 Exam 4

What is the distance from the Earth to the Sun in AU, miles, and Sun diameters?

1 AU, 93 million miles, ~100 Sun diameters

How does the Sun’s diameter compare to the Earth’s diameter?

The Sun's diameter is roughly 109 times larger than Earth's diameter

How does the Sun’s mass compare to the Earth’s mass? Jupiter’s mass?

The Sun's mass is roughly 300,000 times greater than Earth's mass. 1,000 times greater than Jupiter’s mass

What percent of the Sun’s mass is composed of elements heavier than helium?

2%

What is the average rotation period of the Sun?

27 days

What is the surface temperature of the Sun ( ̊F)?

10,000 F

What is the power output of the Sun?

4 × 10^26 Watts (400 YotaWatts)

What is the source of the Sun’s energy?

Fusion

What is the temperature of the core of the Sun ( ̊F)?

27 Million Degrees F (15 Million K)

What percent of the Sun’s total mass has been converted into energy during the 5 billion years that the Sun has been shining?

Less than 0.1%

What kind of particles are used to study the Sun’s core?

Neutrinos

What is the solar neutrino problem?

The number of neutrinos was less than expected

What is the solution to the solar neutrino problem?

The solution involved the discovery that neutrinos come in different flavors and can change flavor as they travel through space

Put the following layers of the Sun in order from the center of the Sun to its outer atmosphere

Radiative zone, Convective zone, Photosphere, Chromosphere, Corona

What causes sunspots to be cooler?

Stronger magnetic fields

What is the period of the solar cycle from maximum solar activity to maximum solar activity?

11 Years

What causes the solar cycle?

Differential Rotation

In what layer of the Sun’s atmosphere are spicules found?

the Chromosphere

What is a solar prominence?

A large, bright loop of cool, dense gas that erupts from the Sun's surface and can loop back down for days or weeks.

What is a solar flare?

A sudden, intense burst of radiation from the Sun's surface, lasting from minutes to hours.

What is a coronal mass ejection (CME)?

A large-scale eruption of plasma and magnetic field from the Sun's corona.

Which lasts longer, a solar prominence or a solar flare?

Prominences

What is the solar wind mostly composed of?

Protons and electrons

Which mission made three solar scans at all latitudes?

Ulysses

Which mission was able to see the whole Sun?

SOHO

Which mission has a set of postage stamps?

SDO

Which mission is studying the Sun up close?

Parker Solar Probe

How much more light gathering power does an 8-inch telescope have compared to a 4-inch telescope?

Four times

What is resolving power?

Ability to discern details (resolution)

What is the purpose of adaptive optics?

Helps overcome atmospheric distortions by adjusting the mirror in real time

What advantage does the Hubble Space Telescope have over telescopes located on the surface of the Earth?

It is above the atmosphere

Why can you see more stars in rural areas than in urban areas?

Less light pollution

What are the advantages of a bigger telescope?

Gathers more light and greater resolution

Why are there no X-ray telescopes located among the Mauna Kea observatories?

X-rays are stopped by Earth’s atmosphere

What country is the Extremely Large Telescope (ELT) located in?

Chile

What telescope is this?

Keck

What telescope is this?

Subaru, Gemini North, Gemini South

What telescope is this?

LBT (Large Binocular Telecsope)

What telescope is this?

JWST (James Webb Space Telescope)

What telescope is this?

GTC (Gran Telescopio Canarias)

What telescope is this?

HST (Hubble Space Telescope)

What telescope is this?

HET (Hobby Eberly Telescope), SALT (Southern African Large Telescope)

What country is Gemini North located in?

USA

What country is Gemini South located in?

Chile

What country is the Gran Telescopio Canarias (GTC) located in?

Spain

What country is the Hobby-Eberly Telescope (HET) located in?

USA

What country (location) is the Hubble Space Telescope (HST) located in?

Low Earth Orbit

What country (location) is the James Webb Space Telescope (JWST) located in?

L2

What makes Mauna Kea a near ideal location for observatories?

Dark skies, good seeing, low humidity, high elevation, low latitude

Which of the largest telescopes in the world are located on Mauna Kea?

Keck Telescopes, Subaru telescope, Gemini North

What is the approximate baseline of the Event Horizon Telescope?

The Event Horizon Telescope has a baseline that spans the diameter of the Earth

At what wavelength did the Event Horizon Telescope make its observations?

1.3mm

How were the telescopes in the Event Horizon Telescope synchronized?

Atomic clocks

How much total data was collected by the Event Horizon Telescope to produce the first image of a black hole?

5 petabytes (5,000 Terabytes)

What is the name of the black hole at the center of our galaxy?

Sagittarius A*

How does the mass of the black hole at the center of our galaxy compare to the mass of M87*?

M87* is 1,000 times more massive

Why is it so difficult to directly image an exoplanet?

Stars near them are too bright

How many confirmed exoplanets have been discovered to date?

5,600+

What country is the Keck Telescopes (Keck I & Keck II) located in?

USA

What country is the Large Binocular Telescope (LBT) located in?

USA

What country is the Subaru Telescope located in?

USA

What country is the Southern African Large Telescope (SALT) located in?

South Africa

What country is the Very Large Telescope (VLT) located in?

Chile

Which observatories on Mauna Kea were part of the Event Horizon Telescope that produced the first image of a black hole?

SMA, JCMT

What country is ALMA located in?

Chile

What country is APEX located in?

Chile

Where is the James Clerk Maxwell Telescope located?

Hawaii

What country is the Large Millimeter Telescope located in?

Mexico

What country is the Pico Veleta Observatory located in?

Spain

What country is the South Pole Telescope located in?

South Pole

Where is the Submillimeter Array located?

Hawaii

Where is the Submillimeter Telescope located?

Arizona

Which observatory is the largest array in the Event Horizon Telescope?

ALMA

Which is the southernmost observatory in the Event Horizon Telescope?

SPT

Which observatory in the Event Horizon Telescope is located by the Large Binocular Telescope?

Submillimeter Telescope

Which is the northernmost observatory in the Event Horizon Telescope?

Pico Veleta Observatory

Which observatory has the largest telescope in the Event Horizon Telescope?

Large Millimeter Telescope

Which observatory in the Event Horizon Telescope is located at the highest elevation?

APEX

Which observatory in the Event Horizon Telescope is an array of 8 – 20 foot telescopes?

Submillimeter Array

When did the Event Horizon Telescope make its observations of M87* in 2017?

April

How was the Event Horizon Telescope data brought together?

FedEx

What caused a six month delay in sending the data from one of the Event Horizon Telescope observatories?

No flights from the south pole in the winter

How does the size of the black hole at the center of our galaxy compare to the size of M87*?

M87* is 1,000 times bigger

Why does the black hole at the center of our galaxy appear to be the same size in the sky as M87*?

Sagittarius A* is 1,000 times closer

Why is the James Webb Space Telescope a good choice for directly imaging exoplanets?

It is an infrared telescope

What are the three main methods for detecting exoplanets?

Astrometric Technique, Radial Velocity Technique, Transits & Eclipses

Which method works best for close stars with distant massive planets?

Astrometric Technique

Which method works best for massive planets that are close to their stars?

Radial Velocity Technique

Which method likely only works for 1% of stars?

Transits & Eclipses

How many stars did the Kepler Mission watch for transits?

150,000

Which method(s) can be used to determine the orbital period of exoplanets?

Astrometric Technique, Radial Velocity Technique, Transits

Which method(s) can be used to determine the eccentricity of exoplanets?

Radial Velocity

Which method(s) can be used to determine the size of exoplanets?

Transit method

What two methods are used to determine the density of exoplanets?

Radial Velocity and Transit

Which method has been used to discover the most exoplanets? What percent?

Transit (74.3%)

What percent of confirmed exoplanets are terrestrials?

4%

What kind of planet was the first exoplanet found around a Sun-like star?

Hot Jupiter (51 Pegasi b)

How many planets have been discovered orbiting TRAPPIST-1?

7

HAT-P-32 b has a density similar to?

A puffed-up marshmallow (not dense at all)