Lesson 2 Flashcards
Explain the Rare Earth Hypothesis
Rare Earth Hypothesis: complex life needs a “Goldilocks” planet like Earth (stable star, right size, liquid water, etc.). These conditions are likely rare, making Earth and complex life uncommon
Explain Climate change, and what causes it.
Climate change describes long-term shifts in temperature and weather patterns across the globe. These changes are largely caused by human activities, primarily greenhouse gas emissions and other human activities such as deforestation and land use.
Explain the Montreal Protocol
The Montreal Protocol, signed in 1987, is a global agreement that successfully tackled the thinning ozone layer. It phased out harmful chemicals like chlorofluorocarbons (CFCs) used in refrigerants, aerosols, and more. By uniting nations, this treaty has allowed the ozone layer to gradually recover, protecting us from harmful ultraviolet radiation.
Describe a dwarf planet and give an example
“A dwarf planet is a celestial body that orbits the sun, is spherical in shape, but has not cleared its orbital path of other debris like a planet. They are smaller than planets but larger than typical asteroids or comets. An example of a dwarf planet is Pluto, located in the Kuiper Belt beyond Neptune.”
Explain the nebular hypothesis
dust. As gravity caused the cloud to condense, it flattened into a disk shape, leading to the formation of planets, moons, and other celestial bodies within this disk around a central mass, which became the Sun.
Will the Universe continue to expand forever?
The future of the universe can totally be predicted if only we know the total of matter it contains.
Discuss the difference between blue giants and red giants.
Blue giants are massive, hot stars in the late stages of their evolution, characterized by their high surface temperatures and blue-white color. They burn through their nuclear fuel quickly, leading to shorter lifespans compared to red giants. In contrast, red giants are cooler, larger stars that have exhausted their core hydrogen, causing them to expand and cool down, leading to their characteristic red hue.
Explain the abundances of the elements
H and He are the most abundant. Abundances of the first 50 elements decreases exponentially. Atomic numbers greater than 50 are very low. Elements having even atomic numbers are more abundant than of odd (Oddo-Harkins Rule)
How has the abundance of hydrogen (H) in the universe changed since the Big Bang?
“Since the Big Bang, the abundance of hydrogen in the universe has remained very high, constituting about 75% of all baryonic matter. While there have been changes in the distribution and concentration of hydrogen due to processes like stellar fusion and nucleosynthesis, the overall abundance of hydrogen has remained relatively constant on cosmic timescales.”
What is the Big Bang Theory?
”
The Big Bang Theory is the prevailing cosmological model that describes the early development and expansion of the universe. It posits that the universe originated from a singular, extremely hot and dense state about 13.8 billion years ago and has been expanding and cooling ever since. This theory explains the observed cosmic microwave background radiation, the abundance of light elements, and the large-scale structure of the universe.”
Explain the Oddo-Harkins rule
Elements having even atomic numbers are more abundant than their immediate neighbors with odd atomic numbers
Write or recite the critical reaction for helium burning in the fusion of 3 alpha particles (triple alpha process) to form the nucleus of Carbon 12.
Explain why Fe is the heaviest element that a star can produce
Elements heavier than iron have fusion reaction with temperature and pressure requirements greater input than those that can occur within the core of a giant star
“What is a planet? According to the International Astronomical Union
(IAU)”
“a) is in orbit around the Sun
b) has sufficient mass for its self-
gravity to overcome rigid body forces
so that it assumes a hydrostatic
equilibrium (nearly round) shape
c) has cleared the neighborhood
around its orbit.”
Explain the key differences of Asteroid belt and the Kuiper belt in terms of their composition and formation
”
The Asteroid Belt, situated between Mars and Jupiter, primarily consists of rocky and metallic objects that failed to coalesce into a planet due to gravitational perturbations from Jupiter. In contrast, the Kuiper Belt, located beyond Neptune, is predominantly composed of icy bodies such as dwarf planets, comets, and icy debris, believed to be remnants from the outer solar system’s formation.”
What is a branch of science which deals with celestial objects, space, and the physical universe as a whole
Astronomy
It is the science of the origin and development of the universe
Cosmology
It is the pattern that appears when the actual brightness and color of many stars are plotted against each other
Hertzsprung-Russell Diagram
Comprises of a system or billions of stars held together by gravity
Galaxy
Our solar system consists of ____ planets
8
