Earth Science test 1

What are atoms of the same element that have different numbers of neutrons called?

Isotopes

What is Carbon-14 used for?

it is radioactive, used for radiocarbon dating to determine the age of ancient fossils and artifacts.

Deep inside stars, temperatures and pressures are incredibly ____. These extreme conditions allow for __________, a process where atomic nuclei combine to form heavier nuclei create all the elements heavier than hydrogen.

high; nuclear fusion

What is this process? A star’s life begins by fusing hydrogen atoms in helium. Four hydrogen nuclei (protons) combine to form one helium nucleus (2 protons, 2 neutrons). This process releases a tremendous amount of energy, which is why stars shine.

Hydrogen to Helium

What is this process? When a star runs out of hydrogen in its core, it begins to fuse helium into heavier elements. Three helium nuclei can fuse to form a single carbon nucleus (6 protons)

Helium to Heavier Elements

What is this process? As the star ages, it can fuse carbon with another helium nucleus to create oxygen (8 protons). The star continues this process, creating elements like neon and magnesium, until its core is mostly iron. Nuclear fusion stops at iron because fusing iron doesn’t release energy; it absorbs it.

Creating Carbon and Oxygen

All of the heavier elements on Earth, including the carbon in our bodies and the oxygen we breathe, were once created inside a star through ____________.

nuclear fusion

Supernova creates all the elements heavier than ______ (for example: gold, platinum, lead, etc.). That is why ______ is rare and valuable.

iron; gold

In more massive stars, this process continues in layers, like an onion. As each fuel source is exhausted, the star’s core gets hotter and _______, allowing heavier and heavier elements to form through fusion. This continues all the way up the periodic table to ____.

denser; iron

Why does it stop at iron? Iron is a special element because it has the most stable nucleus of all. Fusing elements heavier than iron actually ________ energy, it doesn’t release it. This is why a _____’s fusion process comes to a stop once it creates an iron core.

releases; star

When a massive star dies in a huge explosion called a ___________, the immense energy from the _________ allows elements heavier than iron to be created, like ____, _______, ______, and ___________. These explosions then scatter all the new elements, enriching the space around them. This “stardust” (________) can then become part of new stars, planets, and even us!

supernova; explosion; gold; uranium; lead; platinum; nebula

What is the life cycle of a star

stellar nebula → Average star→ Red giant → planetary nebula → White dwarf

Stellar nebula → Massive star→ Red supergiant → Supernova→ Neutron star or Blackhole

How far is Earth from the Sun in AU (Astronomical Units)?

1 AU

How far is Earth from the Sun in km

149,597,870,700

What is the Big Bang theory

a theory that explains how our universe formed

All of time, space, energy and matter were compressed into something smaller than an ____. This energy was an extremely small, ___, dense state and it immediately expanded (cosmic expansion/inflation) everywhere in all directions. The universe is still expanding. After the _________, all of this ______ and matter were released, forming the galaxies, stars, planets, and other celestial objects in the universe.

atom; hot; Big Bang; energy

When did the Big bang occur?

13-14 bya (billion years ago)

When did galaxies form?

10 bya (billion years ago)

When did our solar system form?

4.6 bya (billion years ago)

There is evidence that the universe is still _________.

expanding

There is evidence that the universe is still expanding because of….

1. Red-shift of distant galaxies (Doppler Effect/Shift).

2. Cosmic Background Radiation or Cosmic Microwave Background

What is the Doppler Effect/Shift?

It provides the evidence that the universe is still expanding.

What is Light Spectra, or Spectroscopy?

It is the study of how light from an object is broken down into its different colors, or wavelengths. Think of it like a barcode or fingerprint for light. When you shine light through a prism, it splits into a rainbow, which is a continuous spectrum. However, if the light comes from a hot gas, you’ll see a unique pattern of bright lines (an emission spectrum). If the light from a star masses through a cooler gas, you’ll see dark lines where certain colors have been absorbed (absorption spectrum).

Using spectra and special telescopes, we determine the composition of very _______ objects such as stars, _______, etc.

distant; nebulas

The __________ (EM) __________ is the full range of all types of electromagnetic radiation, which is energy that travels in waves. This spectrum is organized by ________ (the distance between waves) and _________ (how often the waves pass a point), which are related to the wave’s ________. 

electromagnetic; spectrum; wavelength; frequency; energy.

Using ____________, we can see if the light waves are being shifted to either Red end of the spectrum or the Blue end of the spectrum.

spectroscopes.

What is Red Shift?

Light waves moving away from Earth will become longer/expand - Have an increased (long) wavelength.

What is Blue Shift?

Light waves moving towards us will be squeezed/compressed - Have a decreased (short) wavelength.

What are the four parts of Hubble’s Law?

1. Nearby galaxies are moving away from us slower than further away galaxies.

2. Galaxies that are further away are moving faster than galaxies that are close to us.

3. Galaxies that are further away have a greater redshift than galaxies that are closer

4. The universe is expanding

What is Cosmic Background Radiation (CBR)? Also called Cosmic Microwave Background (CMB).

It is the faint, uniform glow of radiation that fills the entire universe, serving as a “baby picture” of the cosmos from about 3800000 years after the Big Bang. The CMB is the residual heat and light from the extremely hot, dense early universe

Imagine the universe when it was brand new, a long, long time ago. It was incredibly hot and full of a thick “___” of tiny particles and light. Light couldn’t travel far in this fog, because it kept _________ into the particles. It was stuck! But as the universe grew bigger, it also started to cool down. After about 380000 years, it was finally cool enough for atoms to form. This cleared up the “fog.” Suddenly, the light was free to ___ everywhere, shooting out in all ______. This first light that was set ___ is the ___________________. It’s the oldest light we can see!

fog; bumping; travel; directions; free; Cosmic Background Radiation.

What is a galaxy?

They are a collection of stars and various amounts of gas and dust that are held together by gravity.

How are Galaxies classified into types?

by shapes

What type of galaxy is the Milky way galaxy.

It is a spiral galaxy.

How far from the galactic center are we?

located 2/3 of the way from the galactic center on one of the spiral arms.

What are stars?

They are a huge balls of gas held together by gravity.

Stars produce tremendous amounts of energy due to _________- the combining of smaller elements to make larger elements.

Nuclear Fusion

_________________ (sometimes referenced as Nuclear Fusion) can only occur in extremely high temperatures and pressures.

Nucleosynthesis

Stars are classified by _________ and _________

temperature; luminosity

What is luminosity?

It measures how bright the star is compared to the sun if all stars were the same distance from the observer.

What is Apparent brightness?

How bright a star appears to be as viewed from Earth.

What is Absolute brightness?

The actual luminosity of a star if they were all the same distance to Earth.

Where did all of the elements on the periodic table come from?

They were “cooked” inside stars through a process called nucleosynthesis. It is basically a cosmic kitchen where elements were made.

What element do all of the elements come from?

hydrogen

Inside the super-hot and dense cores of stars, hydrogen atoms are squeezed and fused together to create ______. this process releases a massive amount of energy, which is why stars shine so brightly. As stars get older and their cores heat up even more they can fuse heavier elements, like _____, _______ and even _____.

carbon; oxygen; iron

When a giant star explodes in a ________, it creates conditions so extreme that it forges even heavier elements, such as gold and uranium, scattering them across space to be used in the next generation of stars and ______ — and even us!

supernova; planets

Where do stars originate from?

clouds of gas and dust molecules

What causes the molecules that make stars to come together?

Gravity

When large enough dust molecules and clouds of gas, there is enough ______ and high enough temps to start nucleosynthesis (nuclear fusion). The ball begins to shine and give of ________________ energy. A star is born. They spend most of their lives as a _______________ star - which depends on mass.

pressure; electromagnetic; main sequence

What determines the fate of a star?

Mass does.

What is the certain path Massive stars will follow?

Main sequence → Red Supergiant → Supernova → Black Hole or a Neutron Star.

How long does it take to turn hydrogen into helium?

7×10^6 years

How long does it take to turn helium into carbon?

7×10^5 years

How long does it take to turn carbon into oxygen?

600 years

How long does it take to turn Oxygen into Silicon?

6 months

How long does it take to turn Silicon into Iron?

1 day

How long does it take for the core to collapse?

¼ of a second

What certain path, will less massive stars (like our sun) follow?

Main sequence → Red Giant → White Dwarf → Black Dwarf.

What part does a nebula play in the beginning of a star’s life?

Where stars are born.

What will our sun likely become in its intermediate stage?

Red giant

What will our sun become in its late stage?

White Dwarf

What three paths does a supernova lead to?

Star-Forming Nebula, Neutron Star, Black hole.

What are the steps to fusion?

Step 1. 1H + 1H → 2H + e^+ +v (neutrino)

Step 2. 2H (deuterium) + 1H → 3He +γ (gamma ray)

Step 3. 3He + 3He → 4He + 1H + 1H + Energy

What happens when two helium-3 nuclei collide and fuse?

It produces a stable helium-4 (4He) nucleus and releasing two protons (1H) that can then be used to restart the chain reaction.

The process involves multiple steps, the net result is the conversion of four protons into one _______ nucleus, with the loss of a small amount of ____ that is converted into energy according to Einstein’s equation, E=mc².

Energy in the Sun The Sun’s energy influences the __________ of all celestial objects in our solar system. Different forms of the __________ and helium atoms contained in the Sun’s core, ________ (²H) and the helium atom (____), are under very high temperatures and pressures. These atoms combine to form helium (_____), while releasing tremendous amounts of energy. The model below shows some information about the Sun.

helium; mass; environment; deuterium; ³He; ⁴He

What are the layers of the sun (from surface to core)?

Photosphere → Convection zone → Radiative zone → Core

What is the photosphere of the sun?

It is the observable layer - gives off electromagnetic energy

What is the temp of the photosphere of the sun?

6700°F - 11000°F or 4000K - 6500K

What is the convection zone?

Convection causes hot material to rise to surface and cool. It creates sunspots and solar flares.

What is the temp of the convection zone?

11000°F - 2 million °F

What is the radiative zone?

Serves as a passage for radiation energy from core to surface.

What is the temp of the radiative zone?

7 million °F

What is the core of the sun?

Nuclear reactions occur

What is the temp of the core of the sun?

27 million °F or 15 million K

State one possible distance of Ceres from the Sun, in million kilometers (km).

Anywhere from 227.9 < x < 778.4

Identify the planet in our solar system with an orbital eccentricity closest to the eccentricity of Ceres. (Ceres has a orbital eccentricity of 0.079)

Mars

At present, Proxima Centauri is the closest star to our Sun. However, Alpha Centauri is more easily visible in the night sky. State the relative luminosity and relative mass of Alpha Centauri compared with the luminosity and mass of Proxima Centauri.

Alpha Centauri has a bigger mas and luminosity than Proxima Centauri.

State the name of the galaxy in which all of these stars are located. ( The stars are Ross 248, Lalande 21185, Barnard’s Star, Alpha Centauri, and Proxima Centauri)

Milky way galaxy.

Identify the nuclear process that produces most of the energy released from all of these stars. ( The stars are Ross 248, Lalande 21185, Barnard’s Star, Alpha Centauri, and Proxima Centauri)

Nuclear Fusion

State the general relationship between a planet's distance from the Sun and the planet's period of revolution.

the greater a planet's distance from the Sun, the longer its period of revolution

State one possible distance from the Sun, in million kilometers, at which an asteroid in the asteroid belt can be found.

227.9 million km ≤ x ≤ 778.4 million km

Calculate how many times greater Mercury's average density is than Neptune's average density.

3 times greater

Identify the force that was primarily responsible for contracting the gas cloud in stage 1 of how a solar system is created.

gravity

State the number of million years ago (mya) for the estimated time of origin of our solar system.

4600 mya

Identify the nuclear process occurring within the Sun at stage 5 that converts mass into great amounts of energy of how a solar system is created

Nuclear fusion

Compared to the terrestrial planets. that formed closer to the Sun, describe two characteristics that are different for the Jovian planets that formed farther from the Sun.

The Jovian planets formed from less dense materials/lower density, and they have a greater equatorial diameter.

Which planet has a period of rotation greater than its period of revolution.

Venus

Identify the name of the galaxy where the Kepler-62 planetary system is located.

Milky way galaxy

Identify the name of the planet in the Kepler-62 planetary system that has the shortest period of revolution, and explain why this planet has the shortest period of revolution.

Kepler-62b is closest to Kepler-62. The closer a planet is to a star, the shorter its period of revolution.

What are Sunspots?

They are places on the Sun that look dark

Sunspots aren’t actually dark, they are just not as ______ as the rest of the sun. They are are also a little bit cooler than the rest of the Sun’s surface. Think of them like a cooler spot on a very ___ lightbulb. The Sun’s surface is about 5,500°C (10000°F), but a sunspot is a cooler 3500°C (6300°F)

bright; hot

Sunspots are caused by the Sun’s ___________. This field can get all twisted up, which stops hear from reaching the Sun’s surface. When this happens, that spot becomes _______ and appears as a sunspot. Sunspots usually show up in pair and in groups. The number of sunspots on the Sun goes up and down in a _____ that lasts about 11 years. This is called the solar cycle.

magnetic field; cooler; cycle.

Sunspots tell us how ____ the Sun is. When there are more sunspots, the Sun is more active. This can lead to big bursts of _____, like solar flares. These bursts can send tiny particles and radiation toward _____. Our planet is protected by a shield called the _____________, these bursts can still affect things here. they can sometimes mess up radio signals and satellites. The good news is that these particles also create beautiful light shows in the sky called the aurora borealis (northern lights) and aurora australis (southern lights), which can be seen near the Earth’s poles.

active; energy; Earth; magnetic field.

Scientists have identified an ________ solar cycle. During this cycle there is an increase and a decrease in the number of dark areas (sunspots) on the Sun’s surface. _____ in the cycle with the highest numbers are called maxima, while periods in the cycle with the _______ numbers are called minima. The graphs below show the output of light energy from the entire disk of the Sun, measured at Earth (Total Solar Irradiance) in watts per meter squared (W/m²), and some information about ______.

11-year; Periods; lowest; sunspots

As a star ages, the _____ in its core gets used up. The core beings to undergo a gravitational collapse and becomes more dense.

hydrogen

Which claim best describes the process of nucleosynthesis in a star?

Heavier elements are produce at the end of a star’s life span as temperatures increase.

What can solar system mean?

Can mean a star, or group of stars, that has non star objects orbiting around it.

Our solar system is the ______ and all of the objects that ______ the sun under the sun’s gravitational force.

sun; orbit

_______ is the star that is the gravitational center of our solar system.

The sun

What is a Geocentric diagram?

An Earth centered solar system