Mastering Astro -- Week 1

Word Bank: Local Group, orbits, solar system, rotates, Milky Way Galaxy, universe 1. Our entire solar system orbits around the center of the ______ about once every 230 million years. 2. The Milky Way and Andromeda galaxies are among a few dozen galaxie that make up our ______. 3.The sun appears to rise and set in our sky because Earth ______ once each day. 4.You are one year older each time Earth ______ around the Sun. 5. On average, galaxies are getting farther apart with time, which is why we say our ______ is expanding. 6. Our ______ is moving toward the star Vega at about 70,000 km/hr.

1. Milky Way Galaxy 2. Local Group 3. rotates 4. orbits 5. universe 6. solar system

Consider the indicated events in the history of the universe that have helped make human life possible. Rank the events based on when they occurred, from longest ago to most recent. To rank items as equivalent, overlap them. Note: If two events occurred within seconds of each other, rank them as equivalent. Events: The Big Bang, Earliest Humans, earliest life on earth, the universe begins to expand, nuclear fusion begins in the sun, dinosaurs go extinct, elements such as carbon and oxygen first exist

1. The Big Bang, the universe begins to expand 2. elements such as carbon and oxygen first exist 3. nuclear fusion begins in the sun 4. earliest life on earth 5. dinosaurs go extinct 6. earliest life on earth

According to current scientific estimates, when did the Big Bang occur? about 20 billion years ago about 14 billion years ago about 10 billion years ago about 4 1/2 billion years ago about 65 million years ago

About 14 billion years ago

Which of the following is not a general difference between a planet and a star? Planets orbit stars, while stars orbit the center of the galaxy. Planets are dimmer than stars. Planets are smaller than stars. All planets are made of rock and all stars are made of gas.

All planets are made of rock and all stars are made of gas.

Which of the following correctly lists our "cosmic address" from small to large? Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe; Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe; Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe.

Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe;

The seasons on Earth are caused by its elliptical orbit around the Sun. True False

False

Which of the following statements does not use the term light-year in an appropriate way? It's about 4 light-years from here to Alpha Centauri. It will take the Voyager spacecraft about 20,000 years to travel just 1 light-year. A light-year is about 10 trillion kilometers. It will take me light-years to complete this homework assignment. The Milky Way Galaxy is about 100,000 light-years in diameter

It will take me light-years to complete this homework assignment.

Using the ideas discussed in your textbook, in what sense are we "star stuff"? The overall chemical composition of our bodies is about the same as that of stars. Movie stars and other people are all made of the same stuff, so we all have the potential to be famous. We could not survive without light from our star, the Sun. Nearly every atom from which we are made was once inside of a star.

Nearly every atom from which we are made was once inside of a star.

Could we see a galaxy that is 20 billion light-years away? Yes, if we had a big enough telescope. No, because it would be beyond the bounds of our observable universe. No, because a galaxy could not possibly be that far away.

No, because it would be beyond the bounds of our observable universe.

Rank the objects based on their distances from Earth, from farthest to nearest: The Sun, Star on far side of Milky Way Galaxy, Star on Far side of Andromeda Galaxy, Orion Nebula, Star near center of Milky Way Galaxy, Star on near side of Andromeda Galaxy, Alpha Centauri, Pluto

Order: Star on far side of Andromeda Galaxy Star on near side of Andromeda Galaxy Star on far side of Milky Way Galaxy Star near center of Milky Way Galaxy Orion Nebula Alpha Centauri Pluto The Sun

When we say the universe is expanding, we mean that: Everything in the universe is growing in size. The average distance between galaxies is growing with time. The universe is getting older.

The average distance between galaxies is growing with time.

Rank the following items that describe distances from longest distance (left) to shortest distance (right): the distance from Earth to Alpha Centauri, one astronomical unit (AU), one light-year, the distance across our solar system (to Neptune), the distance from the sun to the center of the Milky Way Galaxy, The distance from the Milky Way Galaxy to the Andromeda Galaxy, the average distance from earth to the Sun

The distance from the Milky Way Galaxy to the Andromeda Galaxy the distance from the sun to the center of the Milky Way Galaxy the distance from Earth to Alpha Centauri one light-year the distance across our solar system (to Neptune) the average distance from earth to the Sun -- one astronomical unit (AU)

Suppose we look at a photograph of many galaxies. Assuming that all galaxies formed at the same time after the Big Bang, which galaxy appears to us as the youngest? All galaxies would appear to have the same age. The galaxy that appears bluest to us. The galaxy that is closest to us. The galaxy that appears largest to us. The galaxy that is furthest from us.

The galaxy that is furthest from us.

The star Betelgeuse is about 425 light-years away. If it explodes tonight: We'll know because it will be brighter than the full Moon in the sky. We'll know because debris from the explosion will rain down on us from space. We won't know about it until 425 years from now.

We won't know about it until 425 years from now.

If stars existed but galaxies did not: We would probably still exist anyway. We would not exist because life on Earth depends on the light produced by galaxies. We would not exist because we are made of material that required recycling in galaxies.

We would not exist because we are made of material that required recycling in galaxies.

When traveling north from the United States into Canada, you'll see the North Star (Polaris) getting ________. brighter dimmer lower in the sky higher in the sky

higher in the sky

On the cosmic calendar, which compresses the history of the universe into a single year, about when did life arise on Earth? in late January in mid-August in September in mid-December just a few hours before midnight on December 31

in September

On the cosmic calendar, which compresses the history of the universe into a single year, about when did Earth form? very early in January in mid-February in June in early September in mid-December

in early September

A television advertisement claiming that a product is light-years ahead of its time does not make sense because _________. it doesn't specify the number of light-years light-years can only be used to talk about light it uses "light-years" to talk about time, but a light-year is a unit of distance a light-year is an astronomically large unit, so a product could not possibly be so advanced

it uses "light-years" to talk about time, but a light-year is a unit of distance

On the cosmic calendar, which compresses the history of the universe into a single year, about when did early humans first walk on Earth? in June in September in mid-December on December 30 just a few hours before midnight on December 31

just a few hours before midnight on December 31

You are standing on Earth's equator. Which way is Polaris, the North star? on the northern horizon directly overhead 30 degrees up, due West The answer depends on whether it's winter or summer. The answer depends on what time of day (or night) it is.

on the northern horizon

The age of our solar system is about: one-third of the age of the universe. three-fourths of the age of the universe. two billion years less than the age of the universe.

one-third of the age of the universe.

The term observable universe refers to ________. that portion of the universe that we have so far photographed through telescopes the portion of the universe that can be seen by the naked eye that portion of the universe that we can see in principle, given the current age of the universe the portion of the universe that is not hidden from view by, for example, being below the horizon

that portion of the universe that we can see in principle, given the current age of the universe

In winter, Earth's axis points toward the star Polaris. In spring: the axis also points toward Polaris. the axis points toward Vega. the axis points toward the Sun.

the axis also points toward Polaris.

What do astronomers mean by the Big Bang? the explosion of a massive star at the end of its life the event that marked the beginning of the expansion of the universe a gigantic explosion that blew all the galaxies in the universe to smithereens the event that marked the birth of our solar system

the event that marked the beginning of the expansion of the universe

What is the ecliptic? a half-circle extending from your horizon due north, through your zenith, to your horizon due south the Sun's daily path from east to west in our sky the path traced by the Moon's shadow on Earth during a solar eclipse the path the Sun appears to trace around the celestial sphere each year

the path the Sun appears to trace around the celestial sphere each year

Which of the following best describes what we mean by the universe? our Milky Way Galaxy the sum total of all matter and energy a vast collection of stars that number as many as the grains of sand on all the beaches on Earth all the galaxies in all the superclusters

the sum total of all matter and energy

Rank the following items according to their size (diameter) from largest to smallest: Earth, Local Group, our solar system, Jupiter, the universe, the sun, the local supercluster

the universe the local supercluster the Local Group the Milky Way Galaxy our solar system the Sun Jupiter Earth

Beijing and Philadelphia have about the same latitude but very different longitudes. Therefore, tonight's night sky in these two places: will look about the same. will have completely different sets of constellations. will have partially different sets of constellations.

will look about the same.

The North Celestial Pole is 35.0∘ above your northern horizon. This tells you that: you are at latitude 35.0∘ N. you are at longitude 35.0∘ E. it is the winter solstice.

you are at latitude 35.0∘ N.