Exoplanets: Glossary

#

51 Pegasi

51 Pegasi is a Sun-like star located 50.9 light-years from Earth in the constellation of Pegasus. It was the first main-sequence star found to have an exoplanet orbiting it

A

analyze

study or investigate

astronomers

a scientist who studies planets, comets and other space bodies

atmosphere

the air or gases that surround a planet

B

bacteria

a one celled living organism

C

carbon dioxide

a gas given off by animals and taken in by plant

composition

what something is made of; the ingredients or parts making up a substance or object

compressed

to squeeze together

coronograph

an attachment to a telescope designed to block out direct light from a star so that dimmer objects nearby can be seen

D

debris disk

disks of dust and other solid material in orbit around a star; the "leftovers" of the process of planet formation that may indicate presence of exoplanets

decompression

to separate out from a compressed version - spread apart

demoted

to categorize something on a lower level

detected

to find or see

determine

to find or see or understand

diverse

having many differences in type or character, unlike others

Doppler shift

change in the frequency of a wave

dwarf planets

a space body too small to be called a planet

E

enhance

make better

exoplanets

planets that exist orbiting stars other than our own sun

extrasolar planets

planets that exist orbiting stars other than our own sun

G

galaxy

a large system of stars

gaseous

to contain or be made of gas

gravitational

related to gravity

H

habitable zone

the distance from a star most likely to have conditions right for life on a planet

I

inaccurate

not quite true

infared

electromagnetic radiation with wavelengths longer than the red end of the visible light spectrum

L

light-year

distance light travels in one Earth year or 9,500,000,000,000 kilometers (about 93 million miles)

O

orbiting

the curved path of a planet around its sun

P

phenomenon

unusual wonders of space

pulsar

when a massive star runs out of fuel and collapses in on itself, the explosion leaves a very dense neutron star that emits pulses of radiation at regular intervals - a pulsar

R

radial velocity

the speed of an object as it moves toward or away from an observer

repurpose

use for a different purpose than originally intended

rogue planet

a lonely, nonconforming planet

S

satellite

a body that orbits another body

spectroscopy

the study of light passing through matter

starshade

a device positioned between a space-based telescope and a star being observed, intended to block the light from a planet

T

technology

the science of useful tools

transiting

the passage of a planet across its sun

U

universe

all of time, space and its contents

V

venture

project