astronomy unit 7 part 1

while gravity is not considered in special relativity it is considered in

general relativity

moving clocks appear to run

slower compared to clocks at rest

moving lengths appear to be shorter compared with

lengths at rest

einstien’s most famous quation shows the equivalence of

mass and energy

what is the method by which our sun get its energy

nuclear fission

what is nuclear fission

when nuclues becomes unstable and decays into 2 lighter nuclei

the sun is made up of

74% hydrogen and 25% helium

how does nuclear fusion work

by converting lighter elements into heavier elements and creating a situation where the mass of heavier elements is less than the total mass of lighter elements.

how does nuclear fusion work in our sun

by converting hydrogen into helium in the sun’s core (p-p chain)

describe the p-p chain

a proton meets another proton and combines to make a deuterium nucleus plus a positron and a neutrino. They meet another proton and create helium-3 nucleus. Then two helium-3 nucleus combine to make helium-4 and two extra protons.

what is the hydrostatic equilibrium

the balance between pressure and gravity in a star

nuclear fusion occurs in our sun’s

core

how many years does it take a photon to travel to the surface of the sun

1 million

what are the layers of the solar interior

core, radiation, and convection

what is helioseismology

the use of sound waves to study our sun’s interior

during the first stage of a p-p chain what particle is created

neutrino

what are the layers of the solar atmosphere

photosphere, chromosphere, corona

When gas is carried by convection cells to the surface of the sun it creates

granules

why does limb darkening occur

due to our line of sight passing through a line of cool atmosphere near the solar disk

what are the layers of the solar atmosphere

photosphere, chromosphere, and corona

what is the hottest part of the solar atmosphere

photosphere

what are sunpots

regions of the solar atmosphere that are cooler than surrounding region

why are sun spots cooler

because of the blocking of convection by magnetic feilds

what is the rotation period of our sun

27 days

what period does a solar cycle have

22 years

what is solar wind

a continuous stream of hot, low density gas flowing away from the sun

when particles from solar wind interact with earth’s magnetic field they radiate

aurorae

what are solar flares

when the sun’s magnetic field line reconnect and provide the energy to send streams of high energy radiation outward

what are coronal mass ejections

they occur when remaining magnetic energy sends out gas into space

what is solar prominence

when material forms loops around areas of constant magnetic field near the solar surface

what is the maundar minimum

a period of decreased solar activity during the Renaissance period

what is the modern maximum

the recent 70 year period of sustained higher than normal solar activity

during periods of greater solar activity there is a

decrease in the amount of cosmic ray incidents towards earth