Chapter 27

stars and galaxies, phsc

The ecliptic

is the plane of Earth’s orbit

The Sun tends to bloat outward from nuclear fusion, and contract due to

gravity

In what region of the Sun is solar energy generated?

the inner core

With daytime temperatures that can reach 430°C, why is nighttime on Mercury so cold?

very little atmosphere, so heat is lost to space

The Large Magellanic Cloud is

a) an irregular galaxy colliding with the Milky Way galaxy.

b) an unusually bright planetary nebula.

c) a bright nebula within our galaxy.

d) the farthest known object visible to the naked eye in a clear nighttime sky.

a

Describe Mar’s amtosphere what what effect it has?

thin, cold

Describe a quasar in 3 words

energetic, disant, puzzling

Where is our solar system?

Milky way, spiral

The most common galaxy shape is

elliptical

In a museum collection you can likely see a

meteorite not meteoroid

a group of stars named by old astronomers, existed for centuries.

constelation

Ursa Major, Ursa Minor, and Cassiopeia are part of the 88 ___ in the night sky.

constellations

Is the Big Dipper a constellation?

No, it is apart of the Ursa Major

The pairs of stars at the end of its bowl point to ___, the North star. (Tail or Ursa Minor)

Polaris

Constellations are all very different ____ from Earth.

distances

What is the hottest star according to color?

Blue

A blue star is 2x. hotter than a ___ star.

red

Give an example of the hottest blue star

Sirrus

Give an example of the coolest red star

Beetlejuice

T/F - The sun is hot, which is why it emits a yellow hue.

F, due to scattering of light

All stars begin as a

nebula

Nebula

large cloud of gas and dust in space

To transfer from nebula to a prostar, the core temperature reaches 10 million K, which is hot enough to begin ______ of ___ and ____.

thermonuclear fusion

hydrogen

helium

The primary energy source for the sun is

thermonuclear fusion

If thermonuclear fusion emits so much energy, why don’t stars explode?

Hydrostatic Equilibrium

What outward force keeps stars stable?

thermal pressure

What inward force keeps stars stable?

gravity pulls it inwards to try to collapse it

White dwarfs are high or low mass stars?

low

What am I describing?

• Cools for eons until too cold to emit light

  • “Dead stars”, that continue to slowly shrink

White dwarf

White Dwarfs are part of a binary, so it pulls matter from its bud <3, which can lead to what?

nuclear blast, nova

• Shorter life span

• Hydrogen fusion fuel burns at a FASTER rate

• High temperature and pressure

High mass stars

• Longer life span

• Hydrogen fusion fuel burns slowly…

• Lower temperature and pressure

Low mass star

A red giant is much heavier than a red dwarfs, which has the shorter life span?

red giant

T/F - Supernovas can be repeated, while novas cannot.

F, supernova = final

nova = bud helps sustain life

When massive stars collapse (explosion)

supernova

Black Holes and Neutron stars are a result of an explosion of

supernovas

When a supergiant collapses into itself due to the inability to generate heavier elements together through fusion

black hole

Spherical, no bulge, M87

Elliptical

Barred, spiral bulge, Milky Way

Spiral

Local clusters are apart of _____

superclusters

The brightest thing in the universe is

a) Sun

b) Neutron Star

c) Eclipses

d) Quasars

d

When a quasar is 1.55 billion light years away, what does that mean?

we see that as they were 1.55 billion years ago