Science day 2

What is a scientific theory? How is the Big Bang Theory an example of this?

The Big Bang theory is the scientific theory that the universe expanded from an extremely hot, dense early state and expanded over time. In the beginning, it was filled with gamma rays but over time, it stretched into microwaves and will continue stretching

It is a scientific theory because it explains observations and is supported by multiple lines of evidence.

What is Hubble’s Law and how was it discovered?

hubble's Law states that, the farther away a galaxy is, the faster it generally moves away.

Edwin Hubble and other astronomers combined galaxy-distance measurements with observations of redshift in the late 1920s to establish this relationship.

How does Hubble's Law support the Big Bang?

Hubble’s Law shows that distant galaxies are moving away from us, proving that the entire universe is continuously expanding. It shows that space is expanding instead of evrything moving around randomly.

How does the Cosmic Microwave Background Radiation support the big bang?

The Cosmic Microwave Background Radiation (CMBR) supports the Big Bang Theory because it is leftover radiation from the early universe.

• The early universe was extremely hot and dense.

• As the universe expanded, it cooled down, allowing light to travel freely.

• That light has stretched into microwave radiation as the universe expanded.

• Scientists can still detect this radiation today, providing evidence that the universe began in a hot, dense state.

State the region of the electromagnetic spectrum observed in each of the evidence above.

The Cosmic Microwave Background (CMBR) is observed in the microwave region of the electromagnetic spectrum.

Hubble’s Law: Observed using visible light and other regions of the electromagnetic spectrum, especially redshift in the light from distant galaxies.

What is the connection between mass and gravity?

Mass is the amount of matter in an object. The more mass there is in an object, the stronger its gravitational pull.

Describe how stars are formed? Make sure you use the vocabulary listed in your notes to describe each stage and process.

• Nebula Cloud: A giant cloud of mostly hydrogen and helium drifts through space.

• Gravitational Collapse: Cold temperatures cause pockets of gas and dust to clump together. As they collect more mass, their gravity grows stronger and pulls the material inward.

• Protostar: As the material packs tighter and the core heats up, it forms a hot, baby star called a protostar.

• Nuclear Fusion Ignition: Hydrogen atoms begin to smash together and fuse into helium. This process—nuclear fusion—releases massive amounts of energy.

• Main Sequence Birth: The outward push from nuclear fusion balances the inward pull of gravity, and the star officially ignites as a main sequence star

What is Nuclear Fusion?

Nuclear fusion is when 2 atomic nuclei combine together to create a single heaver nucleus, realeasing a massive amount of energy

List reasons why our sun plays an important role in our solar system and life on earth. Make sure to provide examples for the reasons.

Light: Provides energy for photosynthesis.

Life: Supports food chains because plants use sunlight to make glucose.

Heat: Keeps Earth warm enough for liquid water.

Weather: Solar energy drives winds and the water cycle.

Gravity: Holds the planets in orbit around the Sun.

What is a nebula?

A nebula is a giant, cloud of dust, hydrogen, helium, and other ionized gases in outer space

What is the Solar nebular theory?

The solar nebula theory states that the Sun and the planets of our solar system formed about 4.5 to 4.6 billion years ago from the gravitational collapse of a giant, spinning interstellar cloud of gas and dust known as the solar nebula

What is the frost line and what does it indicate in our solar system?

The frost line is the distance from a star where it gets cold enough for gases to freeze into solid ice. between mars and jupiter, after the aesteroid belt. It indicates the sepreation of rocky planets from gas giants.

How did Mars form? How does the formation of Mars explain its properties?

Mars formed about 4.6 billion years ago from dust, gas, and rocky material around the young Sun, making it a small, rocky planet. Its weak gravity makes it difficult to hold onto gases, and iron in its rocks gives it its reddish colour.

How did Jupiter form? How does the formation of Jupiter explain its properties?

Jupiter formed about 4.6 billion years ago beyond the frost line, where ice and rock formed a large core that attracted huge amounts of hydrogen and helium gas. This made Jupiter a massive gas giant with strong gravity that holds many moons.

What is the difference between Jupiter and Mars in the way in which they were formed?

Mars formed close to the Sun, where the heat allowed only rocky materials and metals to form a planet. Jupiter formed farther away, beyond the frost line, where ice and rock formed a large core that attracted huge amounts of hydrogen and helium gas.

What is an exoplanet?

A planet that exists outside our solar system and orbits around a star

Name and describe 2 methods that scientists are using to detect these planets.

1. Transit Method:

• Space telescopes continuously monitor the brightness of thousands of stars. If they see a star's light dim at regular, predictable intervals, it indicates a planet is orbiting it.

2. Doppler method

• Gravity is a two-way street. While a star's gravity keeps a planet in orbit, the planet's gravity also pulls slightly on the star, causing the star to wobble in a tiny circle.

What is the habitable (Goldilocks) zone?

the region around a star where the temperature is just right—not too hot and not too cold—to allow liquid water to exist on the surface of a rocky planet

Why is the detection of water vapour important to search for extraterrestrial life?

Because water vapour is essential for life, and its presence proves an exoplanet has an atmosphere capable of shielding a surface from harmful radiation.