Earth Science Chapter 24

Telescopes

Instruments that help astronomers collect more light and magnify images.

Best ground locations for telescopes

Mountain peaks in dry climates, away from large cities.

Optical telescopes

Telescopes that use lenses or mirrors to gather and focus starlight.

Light gathering power

Depends on the area of the lens or mirror; doubling the radius increases power by four times.

Refracting telescopes

Telescopes that contain two lenses: an objective lens to gather starlight and an eyepiece lens to magnify the image.

Reflecting telescopes

Telescopes that use one large objective mirror instead of a lens.

MMT

A multiple mirror telescope, a type of reflector that has multiple mirrors instead of one larger mirror.

Hubble Space Telescope

Launched in 1990, it observes mostly visible light.

James Webb Telescope

Launched in 2021, it observes mostly infrared light.

Electromagnetic spectrum

The range of wavelengths from radio waves to gamma rays.

Frequency

The number of wavelengths that pass by a point in one second.

Wavelength

The distance between crests of a wave.

Radio Astronomy

The study of radio waves from space.

Infrared telescopes

Telescopes that observe infrared waves; affected by water vapor.

Spectroscope

An instrument that separates light into various colors based on wavelength.

Continuous spectra

An unbroken band of colors produced from glowing solids, liquids, or compressed gases.

Doppler Effect

The compression and expansion of waves caused by the source moving toward or away from the observer.

Red shift

When light from a star shifts toward the red end of the spectrum due to it moving away from the observer.

Solar telescope

Projects large images of the sun in a dark underground room for safe viewing.

Sunspot

A magnetic storm on the sun's surface appearing as dark spots.

Solar wind

Streams of electrically charged particles given off by the corona.

C.M.E

Coronal Mass Ejection; a massive solar flare.

Photosphere

The sun's visible surface that glows yellow due to its high temperature.

Core of the Sun

The nuclear furnace where hydrogen atoms fuse into helium, producing energy.

Fusion in the Sun

The process of hydrogen atoms fusing into helium in the sun's core that produces energy.