Space Science Learning Experience 3

refracting telescope

uses lenses (convex lens)

reflecting telescope

uses mirrors (objective concave or curved mirror), most modern telescopes

optical telescopes

only takes in visible light (includes refracting and reflecting telescopes)

three functions of the telescope?

to gather light, magnify, resolve fine detail

what is the most important function of the telescope?

to gather light

telescope limitations

chromatic aberration (color distortion), sky pollution, satellites, size, and seeing (earth’s atmosphere causes blurring)

spectrometer

measures the spectrum of the source of radiation

spectroscopy

the astronomers most powerful tools; provides information about composition, temperature motion, and other characteristics

Hubble Space Telescope

2.5 meter mirror, observe infrared, visible, and ultraviolet light, orbits earth above the atmosphere

James Webb Telescope

6.5 meter mirror, 1 million miles beyond earth, observes infrared radiation

Cecilia Payne Gaposhkin

found that stars are made up of mainly hydrogen and helium by studying spectral lines

what are the layers of the sun? (innermost to outermost)

core, radiative zone, convection zone, photosphere, chromosphere, corona

core of the sun

extremely dense, source of all energy from the sun, hottest part of the sun (27 million degrees) 

radiative zone

primary mode for transporting energy across it using radiation, light moves very slowly because there’s a lot of bouncing around and energy

convective zone

outermost layer of the interior, transports energy from the edge of the radiative zone to the surface using convection

photosphere

the layer of the sun’s atmosphere we cannot see past, generates no energy, 5800 degrees K

chromosphere

sun’s atmosphere right above the photosphere, “sphere of color,” about 10,000 K, red color due to emission of hydrogen, characterized by large spikes of rising gas 

spicules 

extend upward from the photosphere to the chromosphere, looks like flames or spikes off of the sun 

corona

outermost and hottest part of the sun’s atmosphere, only visible during solar eclipse

coronal holes

large dark regions of the corona (relatively cool) that emit solar wind

solar wind

materials escapes outward from the sun through coronal holes, creates aurora here on earth

sunspots

large dark spots on the surface of the sun caused by increased magnetic activity

differential rotation

the speed of the sun’s rotation varies according to its latitude (24.47 days at the equator, 34.5 days at the poles) 

sunspot cycle/cyclic effect

the total number of sunspots visible at any time within 11 years (includes sunspot maximum and minimum)

Zeeman effect

spectral lines can be split in the presence of a strong magnetic field

plages

bright “clouds” in the chromosphere around sunspots with strong magnetic fields

solar flare

rapid eruption out of sunspots, lasts 5-10 minutes, releases energy equivalent to a million hydrogen bombs. 

what causes the sunspot cycle? 

the sun’s magnetic properties 

magnetic loops

plasma from the sun that follows magnetic field lines

solar dynamo

turbulent layers of gas generate electric currents which form the magnetic field, and because of differential rotation, magnetic fields get “tangled”

Mauder Minimum

fewer sunspots between 1645-1715, cooler temperatures recorded on earth (Little Ice Age)

space weather

the variations in the space environment between the sun and earth

what causes the northern lights?

when electrons collide with atoms and molecules in earth’s atmosphere

Carrington Event

solar storm reached earth magnetic fields, northern lights were visible way more south than usual, affected telegraph system 

coronal mass ejection

a giant erupting bubble of gas that heats up the ionosphere and drags satellites to lower altitudes, distorts earth’s magnetic fields, causes disruptions in cell phone and wireless systems, flights, power outages, and increases exposure to radiation

law of conservation of energy 

energy can change forms, but cannot be created nor destroyed 

theory of relativity

Albert Einstein created the theory that matter can be converted to energy (E=mc²)

antiparticle

corresponding but opposite particle (ie: positron and electron)

neutrinos

particle with no mass that move at the speed of light, can move through a star or planet without being absorbed 

nuclear fusion 

joining together lighter atomic nuclei to form a heavier nuclei, occurs in the sun’s core, mass is lost and energy is released, need extremely high temperature and high density 

nuclear fission

breaking down heavy atomic nuclei into lighter ones, releases energy (not used in stars as they are too light) 

hydrostatic equilibrium 

inward and outward gravitational forces are balanced 

where does sunshine come from?

nuclear fusion

proton-proton chain

fuse 4 hydrogen nuclei to make 1 helium nuclei

Catadiopic - Schmidt Cassegrain Telescope

uses both lenses and mirrors to collect light and bring it to a focus

why are telescopes placed in space?

to get away from earth’s distorting atmosphere and observe wavelengths that cannot pass through the atmosphere (gamma, X ray, UV, infrared)

what is the largest modern research telescope?

10 meters across

what are some modern innovations in research telescopes?

actuators on mirror segments to account for or correct atmospheric distortion

Parker Solar Probe

traveling around the sun to make observations

the sun’s average rotation rate

27 days

what is needed for nuclear fusion to occur?

extremely high temperatures (10 million degrees Kelvin)

Annie Jump Cannon

revised the spectral classification system to be in order of decreasing temperature

what is the spectral classification system?

O, B, A, F, G, K, M

John Von Fraunhofer

developed the spectroscope

William Huggins

observed the spectral line shift of Sirius

Henry Draper

first to photograph a star’s spectra (Vega)

what is the spectral classification of our sun?

G

absorption spectrum

dark lines, created when an electron jumps to a higher energy level or when a continuous spectrum is viewed through a cooler gas

emission spectrum

series of colors, created when electrons fall to a lower energy level or by diffused gas

what is one way that astronomers detect extrasolar planets?

the wobble or wiggle of an unseen planet tugging on its host star

according to the doppler effect, lines are blue shifted when…?

a planet tugs on the star in the direction of earth

according to the doppler effect, lines are red shifted when…?

a planet pulls on a star away from earth

how much energy can a small amount of mass create?

a lot

what are the different types of energy?

potential, kinetic, electromagnetic, and thermal

which spectral class is the hottest, most luminous, and most massive?

O

which spectral class is the coolest, least luminous, and least massive? 

M

how big are most stars?

smaller than the sun

what element can brown dwarf stars only fuse?

hydrogen into deuterium

why do some cool stars appear bright?

they have large surface areas

how do astronomers determine the mass and diameter of stars?

eclipsing binary star systems or spectroscopic observations

about how many stars in our sky are binary stars?

at least half 

What is Wien’s Law?

as temperature increases, wavelength decreases and frequency increases

what does temperature affect in stars?

color

what temperature is the surface of the sun? 

5500 K

what temperature is the core of the sun?

27 million degrees K

if you double the diameter of an objective lens or mirror in a telescope, how does it affect its light gathering?

it quadruples the light gathering

what are the 3 behaviors of waves? 

reflection, refraction, diffraction 

what is formed in the first step of the proton-proton chain?

neutrons

did the sun have more hydrogen or helium 4.5 billion years ago?

hydrogen

how far through its life is the sun?

about halfway through its life (5 billion years) 

blackbody

absorbs nearly all light and radiation

reflection

bouncing light off of something (mirror)

refraction 

bending light between two mediums (lens) 

diffraction

spreading out of light

optical binary stars

can see 2 very close stars with a naked eye

visual binary

can see both stars with an optical aid

spectroscopic binary

separate the two stars spectroscopically (looking at the spectra)

eclipsing binary

star will dim when unseen companion passes in front of it