Astro 150 Trivia - February 16

What is the sun's rough composition?

• 74% Helium

  25% Hydrogen

  1% Everything Else

• 74% Hydrogen

  25% Helium

  1% Everything Else

• 78% Nitrogen

  21% Oxygen

  1% Everything Else

• 51% Hydrogen
  48% Helium
  1% Everything Else

Which part of the Sun produces energy?

• The Core

• The Chromosphere

• The Radiative Zone

• The Convection Zone

Answer explanation

Nuclear fusion takes place in the Sun's core only, therefore this is where the Sun produces its energy.

How do photons move through the radiative zone?

• They shoot right through

• They get stuck there; the photons we see come from the outer layers

• They travel up with bubbles of material

• They scatter off of the dense matter and slowly move outward

Answer explanation

The radiative zone is very dense. It takes a while for photons to make their way out because they're scattering off of all the gas particles there and sometimes bounce back toward the core.

How does energy move through the convection zone?

• Bulk gas motion or boiling

• It gradually moves through dense material

• Energy doesn't move through the convection zone, it's made there

• The energy is carried up on magnetic fields

What layer of the sun do we see sunspots in?

• The chromosphere

• The convection zone

• The photosphere

• The radiative zone

Answer explanation

Sunspots are parts of the photosphere that are cooler than the rest of the sun's surface, so that's where we see the sunspots.

What causes sunspots?

• Atmospheric phenomena in the sun's atmosphere that obstruct our view of the surface

• Bundles of magnetic field

• Blobs of cooler gasses rising up through the convection zone

• We don't know

Answer explanation

These bundles of magnetic field suppress convection, which then lowers the energy output, which then makes the surface a little darker, resulting in sunspots.

Why can't we see the chromosphere normally?

• It's transparent to visible light due to how tenuous (not dense) it is

• Its emissions are not in visible wavelengths

• We can see it normally

Why is the solar corona so hot?

• Solar flares heat it up

• It's actually the coolest layer of the sun

• Magnetic fields excite the electrons in the corona, making them zoom around, which makes this layer hotter

• We don't really know

Answer explanation

It is hypothesized that oscillating magnetic fields help heat up the corona, but it's uncertain if that's the cause or not.

What is the correct order of the layers of the sun (innermost first)?

• Core, radiative zone, convection zone, photosphere

• Photosphere, convection zone, radiative zone, core

• Core, convection zone, radiative zone, photosphere

• Photosphere, radiative zone, convection zone, core

True or False: Kelvin-Helmholtz contraction can provide energy by converting gravitational potential energy to heat.

• True

• False

Answer explanation

True: Kelven-Helmholtz contraction can provide the energy. It plays an important role in different evolutional stages of stars (e.g., very young stars called protostar).