Unit 4: Space Exploration & Cosmology Flashcards

Space Exploration Flashcards

Q: What are four direct methods and three indirect methods of space exploration?
A: Direct: Flybys, Orbiters, Landers, Sample-return missions. Indirect: Wavelength observations, cosmic ray/neutrino detection, high-precision imaging.

Q: Name key space missions for Venus and Mars.
A: Venus: Venera (USSR), Magellan (NASA). Mars: Mariner, Viking, Pathfinder (NASA).

Q: What was the first artificial satellite?
A: Sputnik 1 (USSR, 1957).

Q: What was the first human spaceflight?
A: Yuri Gagarin (USSR, 1961).

Q: Who landed the first humans on the Moon?
A: NASA, Apollo 11 (1969).

Q: What is the Hubble Space Telescope's role?
A: Observes distant celestial objects beyond Earth's atmosphere.

Q: What is the International Space Station (ISS)?
A: A habitable orbiting research lab.

Q: What is the James Webb Space Telescope's role?
A: Infrared observations of early galaxies and exoplanets.

Q: When were radio, X-ray, and infrared telescopes invented?
A: Radio (1930s), Infrared (1950s), X-ray (1960s).

Q: Who made the first reflecting telescope?
A: Isaac Newton.

Cosmology Flashcards

Q: What is the Big Bang Theory?
A: The universe began from a singular point and has been expanding since.

Q: What supports the Big Bang Theory?
A: Redshift of galaxies, cosmic microwave background (CMB), and element abundance.

Q: What is Hubble's Law?
A: Galaxies move away at speeds proportional to their distance, proving expansion.

Q: What is the CMB?
A: Leftover radiation from the early universe, confirming the Big Bang.

Q: What surprising discovery in 1998 changed cosmology?
A: The universe’s expansion is accelerating (dark energy).

Q: What are dark matter and dark energy?
A: Dark matter: unseen mass via gravity. Dark energy: force driving accelerated expansion.

Q: What are quasars?
A: Extremely bright galactic cores powered by supermassive black holes.

Q: What is the fate of the universe in the Big Bang model?
A: Continued expansion, potentially accelerating.

Q: What is the inflation theory?
A: A rapid expansion right after the Big Bang.

Q: What defines the observable universe?
A: The region of the universe we can observe, limited by the speed of light.

Q: What is a galaxy cluster?
A: A group of galaxies held together by gravity.

Q: What is gravitational lensing?
A: Light bending around massive objects, confirming general relativity.

Q: What is the significance of the Andromeda Galaxy?
A: It's the nearest spiral galaxy and will collide with the Milky Way in the future.

ICQ Questions

1. What was the first artificial satellite in space?
   
   

   • Sputnik 1.
     
     

2. What major contribution did Hubble make to cosmology?
   
   

   • Observed galaxy redshifts, leading to Hubble's Law.
     
     

3. What is the significance of the cosmic microwave background?
   
   

   • It provides evidence for the Big Bang theory.
     
     

4. What discovery in 1998 shifted cosmology theories?
   
   

   • The universe's expansion is accelerating (dark energy).
     
     

5. What is gravitational lensing used for?
   
   

   • To study distant galaxies and confirm relativity.
     
     

Summary for Long Answer (Space Exploration & Cosmology)

Space Exploration Summary:
Space exploration involves both direct missions, like orbiters and landers, and indirect observations using various wavelengths. The space race between the USSR and the USA led to key milestones, such as Sputnik 1 (first satellite) and Apollo 11 (first Moon landing). Modern telescopes like Hubble and James Webb extend our reach into deep space, allowing us to study the early universe and exoplanets.

Key Space Exploration Terms:

• Flyby: A space mission where a spacecraft passes close to a celestial body but doesn’t enter orbit.
  
  

• Orbiter: A spacecraft that goes into orbit around a planet or moon to gather long-term data.
  
  

• James Webb Space Telescope (JWST): An advanced infrared telescope designed to observe the earliest galaxies, stars, and exoplanets.
  
  

• International Space Station (ISS): A large spacecraft in low Earth orbit where astronauts live and conduct scientific research.
  
  

• Venera Missions: Soviet missions that explored Venus, providing the first images of its surface.
  
  
  

Cosmology Summary:
Cosmology focuses on the origin and structure of the universe. The Big Bang Theory, supported by the CMB and redshifts, suggests the universe began as a singularity. Hubble’s Law demonstrates expansion, while dark energy explains the acceleration of this expansion. Inflation theory proposes a rapid growth phase shortly after the Big Bang. Gravitational lensing and quasars provide insights into massive cosmic structures, while the Andromeda-Milky Way collision highlights galaxy evolution.

Key Cosmology Terms:

• Big Bang Theory: The leading explanation for the origin of the universe, stating it expanded from a very hot, dense point about 13.8 billion years ago.
  
  

• Cosmic Microwave Background (CMB): The faint glow of radiation left over from the early universe, providing evidence for the Big Bang.
  
  

• Hubble’s Law: A principle stating that the farther away a galaxy is, the faster it is moving away, demonstrating the universe's expansion.
  
  

• Dark Energy: A mysterious force that accelerates the expansion of the universe.
  
  

• Gravitational Lensing: The bending of light from distant objects by massive bodies like galaxies, confirming Einstein’s theory of relativity.