kuiper belt
[noun]
a region beyond Neptune in the solar system containing icy objects like dwarf planets, asteroids, and comets
Ex:
C2 Level Wordlist - Astronomy
Here you will learn all the essential words for talking about Astronomy, collected specifically for level C2 learners.
review
flashcard
spelling
quiz
quasar
[noun]
a highly energetic celestial object emitting powerful radiation from the center of a galaxy, often associated with a supermassive black hole
Ex:
The
high
redshift
of
quasars
suggests
they
existed
in
the
early
stages
of
the
universe
.
oort cloud
[noun]
a distant, hypothetical region surrounding the solar system, thought to harbor icy bodies and comets
Ex:
corona
[noun]
the outer layer of the Sun's atmosphere, observable as a plasma halo during a solar eclipse
Ex:
Solar
missions
,
like
NASA
's
Parker Solar Probe
,
aim
to
explore
the
corona
up
close
and
gather
valuable
data
.
ecliptic
[noun]
the apparent path that the Sun traces in the sky over the course of a year, which is also the plane of the Earth's orbit around the Sun
Ex:
parallax
[noun]
the apparent displacement or difference in the apparent position of an object when viewed along two different lines of sight, often used in astronomy to measure the distance of nearby stars
Ex:
In
surveying
,
the
parallax
in
sighting
between
two
points
helps
calculate
the
distance
and
elevation
changes
.
pulsar
[noun]
a highly magnetized, rotating neutron star that emits beams of electromagnetic radiation from its magnetic poles
Ex:
The
fast
rotation
of
pulsars
,
sometimes
reaching
hundreds
of
rotations
per
second
,
contributes
to
the
periodic
nature
of
their
pulses
.
astronomical unit
[noun]
a unit of measurement equal to the average distance between the Earth and the Sun, approximately 149.6 million kilometers
Ex:
parsec
[noun]
a unit of astronomical distance equivalent to about 3.26 light-years
Ex:
Galaxies
billions
of
parsecs
away
are
visible
with
powerful
telescopes
.
cosmic ray
[noun]
a high-energy particle, mainly originating from outside the Solar System, that travels through space at nearly the speed of light
Ex:
Cosmic rays
are
energetic
particles
that
bombard
the
Earth
from
space
.
cosmic microwave background
[noun]
(cosmology) the faint glow of radiation spreading through the universe, believed to be residual radiation from the Big Bang
Ex:
The
cosmic microwave background
is
the
afterglow
of
the
Big Bang
.
nebular hypothesis
[noun]
(cosmology) a theory proposing that the solar system formed from a rotating nebula of gas and dust about 4.6 billion years ago
Ex:
Astronomers
use
evidence
from
other
star
systems
to
support
the
nebular hypothesis
.
Hubble constant
[noun]
(cosmology) a measure of the rate at which the universe is expanding, determined from the observation of distant galaxies' recession velocities
Ex:
The
value
of
the
Hubble constant
has
been
refined
over the years
.
interstellar medium
[noun]
the matter and radiation that exists in the space between stars within a galaxy
Ex:
Space probes
collect
data
on
the
composition
of
the
interstellar medium
.
heliosphere
[noun]
the space surrounding the Sun dominated by solar wind
Ex:
The
heliosphere
extends
far
beyond
the
orbit
of
Pluto
.
cosmic dust
[noun]
very small particles originally derived from stars, serving as raw material for forming planets, and existing between galaxies, stars, and other celestial bodies
Ex:
Cosmic dust
grains
play
a
crucial
role
in
the
process
of
star
formation
,
serving
as
the
building blocks
for
planets
and
other
celestial bodies
.
meteoroid
[noun]
a small celestial body that becomes visible as a meteor upon entrance into the atmosphere of the earth
Ex:
When
a
meteoroid
enters
Earth
's
atmosphere
and
vaporizes
due to
friction
with
the
air
,
it
creates
a
streak
of
light
known as
a
meteor
or
shooting star
.
inflation
[noun]
(cosmology) the rapid expansion of the universe following the Big Bang
Ex:
Observations
of
the
cosmic microwave background
support
the
idea
of
inflation
.
magnetic storm
[noun]
a disruption in earth's magnetic field caused by solar activity, resulting in variations that can impact electronic systems and communications on earth
Ex:
During
a
magnetic storm
,
the
increased
solar
activity
can
lead
to
disruptions
in
satellite communications
,
power grids
,
and
navigation
systems
.
aurora australis
[noun]
the colored lights, mainly green and red, in the sky seen primarily near the southern magnetic pole
Ex:
The
best
places
to
witness
the
aurora australis
are
in
Antarctica
,
southern
Australia
,
New Zealand
,
and
other
southern
high-latitude
regions
.
aurora borealis
[noun]
the colored lights, mainly green and red, in the sky seen primarily near the northern magnetic pole
Ex:
The
best
places
to
witness
the
aurora borealis
are
in
northern
latitudes
,
such as
Alaska
,
Canada
,
Scandinavia
,
and
Iceland
.
cosmogonic
[adjective]
associated with the phenomena, processes, or theories related to the origin and formation of the universe or celestial bodies
Ex:
Cosmogonic
studies
delve
into
the
birth
of
stars
and
planets
.
nebular
[adjective]
relating to or resembling a nebula, which is a cloud of gas and dust in outer space
Ex:
Nebular
emission
lines
are
spectral
lines
emitted
by
ionized
gases
within
nebulae
.
sidereal
[adjective]
relating to the stars or constellations, especially in terms of their positions relative to Earth
Ex:
Sidereal
measurements
and
calculations
are
based on
the
fixed
positions
of
stars
and
constellations
in
the
night
sky
.