question

The average distance between the Earth and the Sun is defined as being one

answer

Astronomical Unit or AU

question

Consider even the Earth and the Moon. About how many moons would fit across the Earth? (No penalty for wrong guessing.)

answer

4 Moons

question

The Earth's diameter is about 13,000 km while the distance between the Earth and the Moon is about 390,000 km. How many Earth's would fit between the Earth and the Moon?

answer

30

question

Follow the link to the astronmical distances calculator. Use it to answer the following question. http://janus.astro.umd.edu/astro/distance/ How many years would it take to reach the planet Saturn travelling at 5 thousand miles per hour?

answer

18.1

question

The Voyager probes have just passed the edge of our solar system. That's as far out into space as any man made probe has reached. So how close is this to the nearest stars? Let's find out. Go back to the astronomical distance calculator and select the speed of 40700 miles per hour and click the launch button. At this speed, it will take 10 years for the ship to reach Pluto. How many years it will take to reach even the NEAREST to our Sun, Proxima Centauri?

answer

70800

question

What types of distances are typically listed in astronomical units:

answer

Distances in the solar system

question

The Sun is

answer

a star. b. 1 AU from Earth. c. more than 100 times the diameter of Earth.

question

List the objects from smallest to largest

answer

Earth, Solar System, Milky Way, Galaxy Clusters

question

If the nearest star is 4.2 light-years away, then

answer

the light we see left the star 4.2 years ago.

question

3.9x105 is the same as

answer

390 Thousand

question

Light takes about 8 minutes to travel from the Sun to Earth. Light takes about 40 minutes to travel from the Sun to Jupiter. How many astronomical units is Jupiter from the Sun?

answer

4.95

question

Light takes about 8 minutes to travel from the sun to Earth. Mars is approximately 1.5 AU from the Sun. How many light minutes is Mars from the Sun?

answer

12

question

One light year is the:

answer

Distance that light travels in one year, approx 10 to the 13th power or 63,000 AU

question

Our Galaxy is part of

answer

A cluster of a few dozen galaxies. Galaxies are commonly grouped together in such clusters.

question

Solar System

answer

The sun and its planets Your local neighborhood

question

Our Galaxy

answer

Contains our solar system plus billions of other stars and whatever planets orbit around them - in other words, billions of solar systems

question

Universe

answer

Includes everything: all of the galaxies, stars, and planets Including our own galaxy Very small part of it, our solar system

question

Clusters are grouped into

answer

Superclusters These are linked to form long filaments and walls outlining nearly empty voids

question

The nearest star is

answer

4.2 ly from the sun

question

Galaxies

answer

Contain many billions of stars Our galaxy is about 80,000 ly in diameter and contains over 100 billion stars

question

Astronomers describe the brightness of stars using what?

answer

The magnitude scale, a system that first appeared in the writings of the ancient astronomers.

question

The north pole of the earth is located at the top of this picture. If you were located on the boundary between daylight and darkness on the right side of the earth in this picture, would you be experiencing sunrise or sunset? Why?

answer

Sunset. Because Earth rotates counterclockwise when viewed from above Earth's North Pole.

question

A region of the sky containing a recognizable pattern of stars is called a

answer

Constellation

question

The apparent visual magnitudes of four stars are listed below. Of these four stars, which one appears dimmest in the sky?

answer

2.8 Compared to -1.2 -0.5 +0.7

question

The apparent visual magnitude of a star is 7.3. This tells us that the star is

answer

Not visible to the unaided eye

question

How many arcseconds are there in one degree?

answer

3600

question

Objects A and B both have the same angular size, and Object A is closer to us than object B. Which of the following can we conclude?

answer

Object A is dimmer than Object B

question

What is the name of the brightest star in the night sky?

answer

Sirius

question

The _____is the dividing the celestial sphere into northern and southern hemispheres.

answer

celestial equator

question

Constellations that do not set and are always above our horizon are called ____ constellations.

answer

Circumpolar

question

The imaginary boundary between the earth and sky is called the

answer

Horizon

question

The point on the celestial sphere directly above the north pole of the earth is called the

answer

North Celestial sphere

question

The ____is the point on the celestial sphere directly above the south pole of the Earth.

answer

South celestial

question

The point of the sky directly overhead us

answer

Zenith

question

What is the celestial sphere?

answer

The celestial sphere is a representation of how the entire sky looks as seen from Earth.

question

ou live at a latitude of 730 N. What is the angle between the northern horizon and the north celestial pole?

answer

73

question

Suppose an astrophotographer hands you a picture with star trails taken looking toward the north celestial pole. If the star trails are 1/6 of a complete circle, about how many hours was the picture exposed?

answer

4

question

The apparent path of the Sun through the constellations as viewed from Earth is called the

answer

ecliptic

question

Match the description of the Sun's position with the name of the special point on the Sun's path.

answer

The sun is crossing the celestial equator moving north = Vernal Equinox The sun farthest north = Summer Solstice The sun is crossing the celestial equator moving south = Autumnal Equinox The sun farthest south = Winter Solstice

question

On which of the following days will the Sun appear on the celestial equator.

answer

Autumnal Equinox

question

The gradual wobble that changes the orientation of earth's axis in space is called

answer

precession

question

Are we ever able to view the Sun at our zenith in Los Angeles?

answer

No, we are too far north

question

Which of the following best describes why we have seasons on Earth?

answer

The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year.

question

The maximum tilt of the northern hemisphere toward the sun occurs ________.

answer

on the first day of summer

question

The point on the moon's orbit farthest from Earth is called

answer

apogee

question

The region of a shadow that is partially shaded is called the

answer

penumbra

question

The ___ cycle is the roughly 18-year cycle over which the pattern of eclipses repeats.

answer

Saros

question

The region of a shadow that is totally shaded is called the

answer

Umbra

question

The point in the moon's orbit closest to the Earth is called

answer

Perigee

question

The points where the moon's orbit crosses the ecliptic are called

answer

Nodes

question

If there is a new moon today, in how many days will the next full moon occur?

answer

14 or 15

question

From the selections below, which one explains why we cannot see a new moon in our sky?

answer

It is too close to the Sun in our sky

question

What will the phase of the moon be 10 days after a first quarter moon?

answer

waning gibbous

question

At about what time will the moon rise during a last quarter phase?

answer

midnight

question

The moon always shows nearly the same face toward earth because ______

answer

the Moon rotates once in the same amount of time that it takes the Moon to orbit Earth

question

The time for the moon to repeat its cycle of phases is equal to

answer

its synodic period

question

The Full Moon always occurs

answer

when the Moon is directly opposite the position of the Sun

question

By approximately how many degrees does the moon's position change from one day to the next?

answer

13 degrees

question

During which phase of the moon do lunar eclipses occur?

answer

Full moon

question

During a total lunar eclipse

answer

The moon is completely in the umbra of the Earth's shadow and appears to be reddish in color.

question

The moon's orbit is not a perfect circle. Therefore sometimes the moon is closer to the Earth than at others. Perigee is the point in the Moon's orbit that is closest to the Earth. Apogee is the point in the Moon's orbit that is farthest from the Earth. The angular size of the Moon in our sky will be _________.

answer

greatest at perigee and smallest at apogee

question

A totally eclipsed moon glows coppery red because

answer

red light is better able to pass completely through Earth's atmosphere and reach the moon

question

Scientific thinking is

answer

based on everyday ideas of observation and experiments

question

Why is Ptolemy important to the history of astronomy?

answer

Developed the first model of the solar system that made sufficiently accurate predictions of planetary positions.

question

The apparent backward motion of a planet along the celestial sphere is called

answer

Retrograde motion

question

According to Copernicus' model of the solar system a planet undergoes retrograde motion when

answer

Earth passes the planet while they orbit.

question

Which of the statements below were not made by Copernicus in his formulation of a heliocentric model?

answer

a. The celestial spheres do not have just one common center. b. The motions of the Sun are not its motions, but the motion of the Earth. c. All of the spheres revolve around the Sun. d. What appears to be forward and retrograde motion of the planets is natrually due to their motion around us. It's D!

question

What feature of Aristotle's model of the universe was included in the model proposed by Copernicus?

answer

uniform circular motion Yes. Copernicus still believed that the planets moved in uniform circular motion.

question

The apparent shift of a nearby object against the background of more distant stars is called

answer

parallax

question

Which of the following was a contribution by Tycho Brahe?

answer

Detailed observations

question

When Tycho observed the new star of 1572, he could detect no parallax. Why did that result undermine belief in the Ptolemaic system?

answer

This star is farther away than the moon and thus the heavens are not perfect and unchanging.

question

Galileo challenged the idea that objects in the heavens were perfect by

answer

observing mountains on the Moon

question

In his observations of the planet Venus, what was seen by Galileo that could only be explained by Venus revolving around the Sun?

answer

A complete cycle of phases

question

Galileo discovered that the planet Jupiter

answer

Has moons orbiting it

question

Kepler's 1st law states that the orbits of the planets are

answer

Ellipse with the sun located at one focus

question

Where is the focus of the ellipse?

answer

Off center and along the longer axis

question

According to Kepler's 3rd Law, when compared to planets closer to the Sun, those farther away __________

answer

Take longer to revolve around the sun

question

According to Kepler's 2nd Law, at which position will a planet move fastest in its orbit around the Sun?

answer

Perihelion

question

Who used his laws of motion and the Universal Law of Gravity to derive the orbits of the planets, thus explaining WHY the planets moved as they do?

answer

Newton

question

The number of wave cycles that pass in one second is called the

answer

Frequency of the wave

question

Light is one form of _____

answer

electromagnetic radiation

question

The distance between two successive peaks of a wave is called a

answer

wavelength

question

A particle of light is called a

answer

Photon

question

Red light waves have _____ wavelength, _____ frequency, and travel at _____ speed compared to blue light waves when both are in space.

answer

longer, lower, the same

question

Light waves with a wavelength of 800 nm would be in which part of the electromagnetic spectrum?

answer

infrared

question

Which two forms of electromagnetic radiation are useful for observing the stars from the ground?

answer

radio waves visible

question

The units of frequency are given in

answer

cycles per second

question

The ability of a telescope to make an image appear larger is called the

answer

magnifying power

question

Telescopes which use a concave mirror to focus incoming light from the stars are called

answer

reflecting telescopes

question

The ability of a telescope to collect light is called the

answer

light gathering power

question

The large lens or mirror that is used to focus the light in a telescope is referred to as the ____ lens or mirror.

answer

primary

question

The brightening of the night sky by light scattered from aritificial outdoor lighting is called

answer

light pollution

question

The ____ refers to the atmospheric conditions on a given night.

answer

seeing

question

Which of the following best describes the focal length of a telescope?

answer

It is the distance from the lens or mirror to the image formed of a distant light source.

question

What does resolving power measure?

answer

The angular size of the smallest features that can be viewed with the telescope.

question

What is CCD?

answer

It is an electronic detector that can be used in place of photographic film for making images.

question

Which of the following statements best describes the principle advantages of telescopes over eyes?

answer

Telescopes can collect far more light with far better angular resolution.

question

What is the purpose of adaptive optics?

answer

It reduces blurring caused by atmospheric turbulence for telescopes on the ground.

question

Suppose you have two small photographs of the Moon. Although both look the same at small size, when you blow them up to poster size one of them still looks sharp while the other one becomes fuzzy (grainy) looking. Which of the following statements is true?

answer

The one that still looks sharp at large size has better (smaller) angular resolution than the one that looks fuzzy.

question

The angular separation of two stars is 0.1 arcseconds and you photograph them with a telescope that has an angular resolution of 1 arcsecond. What will you see?

answer

The photo will seem to show only one star rather than two.

question

Which of the following best describes why radio telescopes are generally much larger in size than telescopes designed to collect visible light?

answer

Getting an image of the same angular resolution requires a much larger telescope for radio waves than for visible light.

question

Which of the following is not an advantage of a telescope in space over ground-based telescopes?

answer

It is closer to the stars.

question

Which power of a telescope is the least important?

answer

magnifying power

question

We measure the temperature of the stars using the ____ temperature scale.

answer

Kelvin

question

What is absolute zero?

answer

The temperature at which no more heat energy can be extracted.

question

Atoms contain three types of particles. In the nucleus there are positively charged ____ as well as ____ which have no charge. Orbiting the neucleus are negatively charged _____ .

answer

Proteins, Neutrons, electrons

question

The lowest possible energy level an electron can occupy is referred to as the ____ state, while higher energy levels are called ____ states.

answer

Ground, excited

question

The chemical element of an atom is determined by the number of _________ it contains.

answer

Protons

question

Carbon-14 is an example of an isotope of Carbon. In this case, fourteen is the number of ___________ in the isotope.

answer

protons and neutrons combined

question

Considering the transitions in a hydrogen atom, which transition results in the emission of a photon with the shortest wavelength?

answer

n=5 ----> n=1

question

An atom that has fewer electrons than protons is called ________.

answer

An ion

question

Which of the following can be determined by examining the spectrum of a star?

answer

(Check all that apply) Choose all that are correct a. constellation b. chemical composition X c. diameter d. mass e. surface temperature X

question

According to the laws of thermal radiation, hotter objects emit photons with

answer

shorter average wavelengths

question

Suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you?

answer

the wavelengths of spectral lines in the star's spectrum

question

Which of the following statements is not true regarding the Sun?

answer

It has a spectral class of F2

question

Betelgeuse is the bright red star representing the left shoulder of the constellation Orion. All the following statements about Betelgeuse are true. Which one can you infer from its red color ?

answer

Its surface is cooler than the surface of the Sun.

question

What conditions produce an absorption line spectrum?

answer

a hot solid, liquid, or high-density gas

question

Examine the figure shown here and consider the following absorption line spectra of four stars. Star W has medium strong hydrogen lines and weak ionized calcium lines. Star X has medium strong hydrogen lines and medium strong helium lines. Star Y has weak hydrogen lines and strong ionized calcium lines. Star Z has weak hydrogen lines and strong ionized helium lines. List these stars in order of surface temperature from highest to lowest.

answer

Z, X, W, Y

question

Suppose that you take the spectra of several stars and identify the 656 nm line of hydrogen. You then measure against the reference spectrum on the same image and find that some of the 656 nm lines are shifted due to the Doppler effect. Of the following shifted locations of this line, which one is that of a star that is moving away from us at the highest speed?

answer

star E at 659 nm

question

If a certain star emits radiation that has a peak wavelength of 550 nm, the temperature of the star is

answer

5300

question

The bright, visible surface of the Sun is called the

answer

Photosphere

question

The outermost layer of the Sun's atmosphere is called the _____and is made of extremely hot very thin gasses.

answer

Corona

question

The layer of the solar atmosphere between the visible surface and the corona is called the

answer

chromosphere

question

The mottled appearance of the Sun's surface caused by rising currents of hot gas and sinking currents of cooler gas is called

answer

granulation

question

____are blotches on the Sun's surface that appear darker than the surrounding regions.

answer

sunspots

question

______ are composed of ionized gas trapped in a magnetic arch rising above the surface of the Sun. When seen along the edge of the Sun, they appear pink in color. However, when seen against the Sun's bright surface they appear as dark _____

answer

prominence, filaments

question

The Sun's mass is about _________ times that of the Earth.

answer

300,000

question

What is caused by the effect known as limb darkening.

answer

The Sun appears dimmer at the edge and brighter at the center

question

The Sun's surface churns with a bubbling pattern called grannulation. Why?

answer

We are seeing hot gas rising and cool gas falling due to the convection that occurs beneath the surface.

question

What effect does the formation of negative hydrogen ions in the sun's photosphere have on solar observations?

answer

The extra electron absorbs different wavelength photons making the photosphere opaque.

question

As one moves outward from the photosphere to the corona, what happens to the temperature and the density of the gases?

answer

The temperature of the gases increases The density of the gases decreases

question

What is responsible for the sunspots on the Sun's surface?

answer

the sun's magnetic field

question

What is the source of the sun's changing magnetic field?

answer

the differential rotation of the sun and convection beneath the photosphere.

question

What is the net result of the proton-proton chain?

answer

4 hydrogens are fused into 1 helium + energy

question

Which statement best describes what was called the solar neutrino problem?

answer

Early experiments designed to detect solar neutrinos found them, but in fewer numbers than had been expected.

question

Which of the following formulas can be used the calculate the amount of energy produced by the mass lost during nuclear fusion?

answer

E = m c2

question

The proton-proton chain is ____

answer

the specific set of nuclear reactions through which the Sun fuses hydrogen into helium

question

What heats the chromosphere and corona to high temperatures?

answer

fluctuating magnetic fields from below that transport energy outward

question

Enter the spectral classes in order from hottest to coolest. Put NO SPACING between the letters. For example: WEISFUN

answer

OBAFGKM

question

The properties of ____ binary systems are detected by examining a light curve.

answer

eclipsing

question

A ____ binary system in which both stars can be observed distinctly as they obit each other.

answer

visual

question

The total amount of energy a star radiates in one second is called its

answer

luminosity

question

A pair of stars which orbit each other is called a _____star system.

answer

binary

question

We can detect the binary nature of a _____ binary star system by the dopler shifts in its spectral lines.

answer

spectroscopic

question

If Star A is closer to us than Star B, then Star A's stellar parallax is

answer

larger than that of Star B.

question

Ten parsecs is about

answer

32.6 light-years

question

According to the inverse square law of light, how will the apparent brightness of an object change if its distance to us triples?

answer

Its apparent brightness will decrease by a factor of 9.

question

At what distance must a star be to have its apparent magnitude equal to its absolute magnitude?

answer

1 AU

question

Which magnitude gives the most information about the physical nature of a star?

answer

absolute bolometric magnitude

question

A star has an apparent magnitude of 3.0 and is located at a distance of 2.5 pc. If this star were located at the standard distance of 10 pc, it would appear to be ___ to us. Therefore its absolute magnitude will be ____ 3.0.

answer

Dimmer, greater than

question

Place the colors of the stars in order from hottest to coolest.

answer

Blue, white, yellow, orange, red

question

Stars with the same spectral class will have the same ____

answer

surface temperature

question

The spectral classes of several stars are given below. List the stars in order from hottest to coolest.

answer

Hottest to Coolest B9, A1, F0, F6, G2, K3, K4, M

question

Can a cool star be more luminous than a hot star?

answer

Yes, if the cool star is larger than the hot star.

question

The axes on a Hertzsprung-Russell (H-R) diagram represent ____

answer

Luminosity and surface temperature

question

Rank the following stars from the H-R diagram in order of temperature from coolest to hottest: Arcturus, Deneb, Spica, Sun, Wolf 1346

answer

Coolest to hottest Arcturus, Sun, Deneb, Wolf 1346, Spica

question

Rank the following stars from the H-R diagram in order of size from largest to smallest: Antares, Barnard's Star, Deneb, Procyon B, Sirius A

answer

Antares, Deneb, Sirius A, Barnard's star, procycon B

question

Rank the following stars from the H-R diagram in order of luminosity from brightest to dimmest: Barnard's Star, Betelgeuse, Pollux, Spica A, Sirius B

answer

Brightest to smallest Betelgeuse, Spica B, Pollux, Sirius B, Barnard's Star

question

The luminosity class of the star Alphard is II which means that

answer

Alphard is a bright giant.

question

Each choice below lists a spectral type and luminosity class for a star. Which one is a red supergiant?

answer

Spectral type M2, luminosity class I

question

Two stars with the same luminosity class will have the same luminosity.

answer

False

question

What is the distance to a star that has an apparent magnitude of 1.5 and an absolute magnitude of -3.5?

answer

100

question

Which of the following statments best describes the gas pressures inside of stars?

answer

The gas pressure is greatest at the center and decreases toward the star surface.

question

The CNO cycle is a series of steps which occur in high mass stars that results in the fusion of __

answer

hydrogen into helium

question

Which stars produce most of their energy by the CNO cycle?

answer

upper main-sequence stars

question

Which of the following stars will spend the most time as a main sequence star?

answer

1 solar-mass star

question

Which property of the star directly indicates the rate at which energy is produced inside that star?

answer

Luminosity

question

Why is there a lower mass limit of 0.08 solar-masses for main-sequence stars?

answer

Objects below this mass are not hot enough to fuse normal hydrogen.

question

Why is there an upper mass limit for main-sequence stars of about 100 solar masses?

answer

Objects above this mass fuse hydrogen too quickly and cannot stay together.

question

What percentage of a stars total fusion lifetime is spent as a main sequence star?

answer

90%

question

Calculate many years will a star with a mass of 0.7 Msun spend on the main sequence?

answer

24.4 billion years

question

What happens when a main-sequence star exhausts its core hydrogen fuel supply?

answer

The core shrinks while the rest of the star expands.

question

What is a helium flash?

answer

The sudden onset of helium fusion in the cores of some giant stars.

question

As the Sun leaves the main sequence to become a giant, its luminosity will_____ while its surface temperature _____.

answer

Increase, decreases

question

Which of the following is required in order for a helium flash to occur?

answer

A degenerate helium core.

question

Which of the following describes a region with a diameter of 25pc containing anywhere between 10 and 1000 stars?

answer

open clusters

question

galactic clusters

answer

A structure that consists of anywhere from hundreds to thousands of galaxies bound by gravity. Galaxy clusters are much larger than galaxy groups. One of the key features of clusters is the intracluster medium or ICM. The ICM consists of heated gas between the galaxies and has a temperature on the order of 7-9 keV. Galaxy clusters should not be confused with star clusters such as open clusters, which are structures of stars within galaxies, as well as globular clusters, which typically orbit galaxies.

question

Which is much larger, Galaxy clusters or galaxy groups?

answer

Galaxy clusters

question

What should not be confused with star clusters?

answer

Open clusters, which are structures of stars within galaxies, as well as globular clusters, which typically orbit galaxies.

question

What information about a star cluster can be obtained by examining its turn-off point on an H-R diagram?

answer

The age of the cluster

question

Which of the following would be classified as an RR Lyrae variable?

answer

a G giant with a period of 14 hours

question

Any star that changes its brightness in a periodic way is called a____ star.

answer

variable

question

Which of the following would be classified as an Cepheid variable?

answer

K giant with a period of 14 days

question

The fairly flat, circular part of the galaxy is referred to as the

answer

disk

question

The center of the Galaxy is in the direction of the constellation

answer

sagittaruis

question

Which is the correct description of the Sun's location in the Milky Way galaxy.

answer

In the disk, about two-thirds of the way out from the center.

question

The location of the center of our galaxy was first determined by observations of

answer

globular clusters

question

About how many stars are in the Milky Way?

answer

100 billion

question

Which of the following is not a part of our Milky Way?

answer

ring galactic bulge b. disk c. spiral arms d. ring X e. halo

question

Which of the following is not typical of the Galaxy's spiral arms?

answer

a. emission nebulae b. young star clusters c. O stars d. globular clusters X

question

We can estimate the mass of the Galaxy from observations of

answer

radial velocities, proper motions, and distances of stars

question

How do stars in the galactic disk orbit the center of the galaxy?

answer

In nearly circular paths and in roughly the same plane.

question

How do stars in the galactic halo orbit?

answer

hey have randomly oriented orbits.

question

What fundamental principle did Shapley use to calibrate the period-luminosity relationship for Cepheid variable stars?

answer

Objects with large proper motion tend to be closer than objects with small proper motion.

question

What must be measured to determine distance by the Cepheid variable star method?

answer

the apparent magnitude and the period of pulsation of the variable star

question

What is the approximate diameter of the disk component of the Milky Way Galaxy?

answer

80,000 ly

question

Which of these two figures illustrates the orbits of population II stars?

answer

3 Model of Galatic plane, ellipses and halo stars

question

Why do astronomers propose that the Milky Way Galaxy contains a lot of dark matter?

answer

The Galaxy's rotation curve flattens out at great distances.

question

How are population II stars different than the sun, a population I star?

answer

Population II stars are lower in metals than population I stars.

question

What do we observe at radio, infrared, and X-ray wavelengths near the center of the Milky Way Galaxy that leads us to conclude that a supermassive black hole is located there?

answer

b. a rapid rate of star formation c. a strong source of radio waves called Sagittarius d. supernova remnants All of these

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