Space Flashcards
(21 cards)
What is a satellite?
A satellite is an object in space that orbits around a larger object.
How do satellites orbit the Earth?
Satellites orbit the Earth when their speed is balanced by the gravitational pull of Earth; their horizontal speed allows them to continuously ‘fall’ towards Earth while circling it.
How does the Moon orbit the Earth naturally?
The Moon naturally orbits Earth by continuously falling towards it while moving forward, creating a stable orbit.
What are some uses of satellites?
Uses include telescopes and detectors for space exploration, global positioning systems (GPS), satellite television for worldwide broadcasting, and weather forecasting.
What is the period of a geostationary satellite?
The period of a geostationary satellite is 24 hours.
What is the altitude of a geostationary satellite?
The altitude of a geostationary satellite is approximately 36,000 km above Earth.
How does altitude affect the period of a satellite?
The higher the altitude of a satellite, the longer the period, because the satellite has a greater distance to travel during one orbit.
What is a major problem for space travel?
A major problem is that sufficient energy is required to power the life support systems for space travel.
What are the risks of space travel?
Risks include exposure to radiation, danger during re-entry into the atmosphere, risk of ignition and explosion due to fuel load at take-off, and the risk from pressure differentials between the vacuum of space and the spacecraft’s internal atmospheric pressure.
How does a rocket launch into space?
A rocket launches into space using Newton’s third law: every action has an equal and opposite reaction. Burning fuel generates downward exhaust, which creates upward thrust that propels the rocket against gravity.
What is Newton’s Third Law?
Newton’s Third Law states that every action has an equal and opposite reaction.
What is a light year?
A light year is the distance that light travels in a year.
How many seconds are in one year?
31,536,000 seconds.
What is the approximate distance of a light year in meters?
9.5x10^15 meters.
What does the Big Bang Theory state?
The Big Bang Theory states that all current and past matter in the Universe came into existence at the same time from a small point of energy that exploded with extreme force.
How long ago did the Big Bang occur?
Around 13.8 billion years ago.
What does spectroscopy allow us to do?
Spectroscopy allows us to identify what elements distant stars and planets contain by observing their unique light spectra.
What can be observed using a line spectra?
The unique emission or absorption lines that correspond to specific elements.
What is a continuous spectrum?
A continuous spectrum shows an unbroken sequence of frequencies or colors.
What is an absorption line spectrum?
An absorption line spectrum shows dark lines where light has been absorbed by elements.
What is an emission line spectrum?
An emission line spectrum shows bright lines where elements emit specific wavelengths of light.
