Astronomy Exam 1

Q1 study quide into flashcards

ecliptic

Imaginary path the sun traces

nadir

Point directly below you

zenith

point straight up

Right ascension

[longitude] hours (24) around

declination

[latitude] day

illuminated

does not give off it's own light {only reflects light}

luminous

amount of light emitted by an object

incandescent

An object that glowed at a high temperature(e-)

fluorescent

A gas lower photon energy

wavelength

Spectral line with identical points on a waveform

frequency

The rate at which waves pass/completes in a given point or rotation.

Approximately how many degrees of the sky is each of these held at arm's length? (open hand, closed fist, Pinky)

open hand: 20°
closed fist: 10°
pinky: 1°

what are 3 main uses for astronomy in ancient times?

1. Survival
2. seasonal change
3. navigational purpose

For a sundial to work properly, in which direction must it be pointed?

North

What did Eratosthenes accomplish, related to the earth?

Compared shadows(track time) at different locations to determine the side of the earth.

describe the relationship between the wavelength of light and its energy?

As wavelength goes down, Energy goes up

The following forms of electro-magnetic radiation from lowest to highest energy:

Radio- microwave- infrared(IR)- blue- green- yellow- ultraviolet- (x-ray)- gamma

What is the most important property for the image clarity of a visible light telescope?

Light collecting power, aperture size, quality, observing site (mountaintops) eyepiece.

Why are large, ground based telescopes usually placed on top of mountains?

1. less atmosphere
2. less light pollution
3. less clouds

describe refracting:

uses lens to collect light to see distant objects & light.

Describe reflecting telescope:

telescopes which a mirror is used to collect & focus light reflects them off a curved mirror.

what are the advantages of using a reflecting telescope compared to a refracting telescope?

Able to be supported from underneath, be built big, and can be built in pieces

What are some advantages and disadvantages of radio telescopes?

Advantages:
1. use during the day and bad weather
2. look at wavelengths that don't penetrate our atmosphere
Disadvantages:
1. expensive, may be difficult to fix or impossible
2. has to be big tp catch a cleat image.

What does each space-based telescope's wavelength specialize in "seeing"; Hubble, JWST, Chandra?

Hubble- sees visible
JWST- sees larger portion of infrared spectrum(IR)
Chandra- sees x-ray

what purpose did the Kepler space telescope serve? How?

Planet hunting telescopes that watches the brightness of 100,000 stars for planet transit.

what two sections of the electro-magnetic spectrum are able to pass through our atmosphere without much interference?

visible light + radio waves

Why do astronauts appear to be floating when they are filmed in space?

Objects fall 5 meter/ 1sec, constantly fall around the earth, at the same rate you would be weightless.

what did project mercury accomplish for NASA?

Got American into space, red stone missile, atlas rocket, Alan shepherd (15 miles)

What did project Gemini accomplish for NASA?

moon landing is possible, more than 1 astronaut and less than 10 days, EVA, Rendezvous/docking

What did commander Scot Kelly do? what kinds of challenges did he face?

four space flights, he had to deal with the physical, cognitive, and genetic toll. He beat the American record.

Changes for orbiting astronaut sensorimotor:

can impair, movement control

Changes for orbiting astronaut Cardiovascular:

reduced oxygen intake, poor physical

Changes for orbiting astronaut Spine:

Expansion of vertebrae, stretch, slightly taller

Changes for orbiting astronaut muscle:

muscle fibers shrink leaving a person weaker

Changes for orbiting astronaut radiation:

radiation sickness & cancer

Changes for orbiting astronaut Bones:

loss of bones mass & bone material

Changes for orbiting astronaut sleep:

lack of sleep & psychological problems

spectroscopy

Each element will produce a unique pattern of colors that it will either emit(out) or absorb(in)

The Doppler effect

a moving wave source will cause waves to Bunch up in front & stretch out behind.
"blue shift" = short wave
"red shift" = longer wave