Astronomy MegaSet

What is the relationship between a star's color and its temperature?

Blue stars are hotter than red stars

What is astronavigation?

Using celestial bodies for navigation

What component makes up the majority of a star's composition?

Hydrogen gas

What is the primary reason astronomers use spectroscopy to study stars?

To determine star composition and temperature

Main sequence stars spend most of their time:

Converting hydrogen to helium

What is a blackbody radiator?

A complete light absorber

What are circumpolar constellations?

Constellations that appear to circle Polaris

What does the H-R diagram compare?

Absolute magnitude and surface temperature

How many hydrogen atoms combine to create one helium atom in stellar fusion?

Four

What is the celestial sphere?

An imaginary coordinate system enclosing Earth

What tool helps astronomers study the evolution of stars over time?

H-R diagram

What color appears to be associated with the coolest stars?

Red

What development helped ancient astronomers calculate celestial body movements?

Geometry

What causes stars to appear to move across the night sky?

Earth's rotation

What are stars primarily composed of?

Hot gases and plasma

What particles make up the light energy emitted by stars?

Photons

According to the text, approximately how many Earths could fit inside our Sun?

One million

A white dwarf is:

A remnant star that has exhausted its fuel

What is Polaris most commonly known as?

The North Star

 More massive stars typically:

Evolve faster and die sooner

 The Milky Way's center contains:

A black hole

A pulsar is defined as:

A spinning neutron star

Who discovered the relationship between a pulsar star's luminosity and its pulsation period?

Henrietta Swann Leavitt

 A star's evolution primarily depends on its:

Initial mass

 Which force counteracts gravity's attempt to collapse a star?

Energy from nuclear fusion

Which waves have the highest frequency in the electromagnetic spectrum?

Gamma rays

What is spectroscopic parallax used for?

Estimating stellar distances

What is the event horizon of a black hole best described as?

The outer perimeter marking the point of no return

What is an indicator of a black hole's presence in a galaxy?

Matter spinning around the center

 What is the relationship between an object's mass and its gravitational effect on space?

Greater mass creates greater curvature

Why would a clock appear to stop if you were moving away from it at light speed?

The light would never reach your eyes

What happens to the laws of physics at the singularity?

They no longer seem to apply

In Einstein's special relativity, what happens to time for an object traveling at the speed of light?

It stops completely

Which statement about wormholes is correct according to the passage?

They're only science fiction so far

What is the Schwarzschild radius?

The critical size at which an object becomes a black hole

Which scientific theory provided the foundation for modern understanding of black holes?

Theory of General Relativity

What causes a supernova?

Gravitational collapse

How does time dilation affect someone orbiting very close to a black hole compared to Earth observers?

They experience time faster

According to Einstein's theory, what happens to space around massive objects?

It curves inward

What is Hawking Radiation?

Energy loss through particle-antiparticle pairs

How do we know black holes exist if we can't see them directly?

Through their gravitational effects

What characteristic defines a singularity?

Its infinite density

According to the text, what principle allows us to see objects?

Light reflection returning to our eyes

According to the text, what happens to a black hole's surface area when matter falls into it?

It grows proportionally

 What happens to matter once it passes the event horizon?

It inevitably moves toward the singularity

What phenomenon causes an object approaching a black hole's event horizon to appear frozen in time to an outside observer?

Time dilation

What is a quasar?

A quasi-stellar radio source formed when black holes accrete matter rapidly

The motion of galaxies moving away from each other is known as:

Hubble flow

When light from a galaxy appears redder, it indicates the galaxy is:

Moving away from us

Why can't we see the entire Milky Way from Earth?

We are located within the galaxy

What are the four main parts of a spiral galaxy?

Halo, bulge, disk, and arms

What is the primary characteristic that defines irregular galaxies?

Their lack of organized structure

 Approximately how many galaxies are in the Local Group?

40

Dark matter's presence can be detected through:

Gravitational lensing

Where are open clusters typically located?

Along the spiral disk

The process where gravity pulls matter into a central source in a spiraling manner is called:

Accretion

In spiral galaxies, where are black holes typically located?

In the nuclear bulge

What galactic supercluster contains the Milky Way?

Virgo Supercluster

 What type of galaxy is the Milky Way?

Barred spiral galaxy

Where is our solar system located within the Milky Way?

Orion arm

What distinguishes newly formed open clusters?

Bright blue stars

How many galaxies are estimated to exist in our universe?

Between 50 billion and one trillion

Which part of a spiral galaxy contains billions of tightly wound lanes of stars?

The spiral arms

What important concept about galaxy observation is mentioned in the text?

The light we see from distant galaxies shows us their ancient history

How many stars can a typical globular cluster contain?

Approximately one million

What characterizes elliptical galaxies?

Spherical clusters with old stars

Young galaxies typically appear what color due to their star formation?

Blue

What is the approximate age of the Milky Way galaxy?

13.5 billion years

 What significant discovery did Edwin Hubble make in 1924?

He discovered that fuzzy blobs of light were actually other galaxies

What are the three major groups that galaxies are classified into?

Spiral, elliptical, and irregular

 What is the diameter of the Milky Way galaxy?

100,000 light-years