Theoretical radiation astronomy/Quiz

Theoretical radiation astronomy is the key theory lecture for the course on the principles of radiation astronomy.

The images show a relativistic jet emanating from the active galactic nucleus of M87 using X-ray, radio, and optical astronomy. Credit: NASA/CXC/VLA/HST.

This is a quiz based on the lecture that you are free to take at any time or knowledge level.

Once you’ve read and studied the lecture itself, the links contained within the article/lecture, listed under See also, External links and in the {{principles of radiation astronomy}} template, you should have adequate background to take the quiz and score highly.

As a "learning by doing" resource, this quiz helps you to assess your knowledge and understanding of the information, and it is a quiz you may take over and over as a learning resource to improve your knowledge, understanding, test-taking skills, and your score.

This quiz may need up to an hour to take and is equivalent to an hourly.

Suggestion: Have the lecture available in a separate window.

Enjoy learning by doing!

Quiz

Point added for a correct answer:
Points for an incorrect answer:
Ignore the questions' coefficients:

	TRUE
	FALSE

	throwing a beam
	a stream of charged or neutral particles
	calculating the energy of a beam
	sending out a traveling ray
	a secondary-object hazard

A neutron star is a type of

that can result from the

of a

during a

supernova event.

	TRUE
	FALSE

	catching a beam
	a stream of charged or neutral particles
	it may appear as a dome over the Earth your standing on
	impervious to some traveling rays
	a secondary-object hazard

	a core which emits neutrinos
	a charged particle wind which emanates out the polar ionosphere holes
	gravity
	near the barycenter for the Earth-Moon system
	the swirls of tan, green, blue, and white are most likely sediment in the water
	coronal clouds
	chlorophyll-containing phytoplankton aloft in the upper atmosphere

The standard solar models have enjoyed tremendous success recently in terms of agreement between the predicted

and the results from

but some

of the Sun still defy explanation, such as the degree of

depletion.

	Yes
	No

	catching a beam
	one more degree of freedom than can be measured or controlled
	it may appear as a dome over a small portion of the Earth your standing on
	impervious to some traveling rays
	a secondary-object hazard

	a core which emits neutrinos
	a charged particle wind which emanates out of a beam line
	gravity
	near the barycenter for the Earth-Moon system
	swirls of tan, green, blue, and white in the water
	electric arcs
	chlorophyll-containing phytoplankton aloft in the upper atmosphere

In the radiation physics laboratories here on Earth, the

,

, and

of radiation is studied and

relative to sources are proven.

	TRUE
	FALSE

	catching a beam
	one more degree of freedom than can be measured or controlled
	it may appear as a dome over a small portion of the Earth your standing on
	impervious to some traveling rays
	a secondary-object hazard

	background radiation
	a charged particle wind which emanates out of a beam line
	gravity
	near the barycenter for the Earth-Moon system
	swirls of tan, green, blue, and white in the water
	electric arcs
	chlorophyll-containing phytoplankton aloft in the upper atmosphere

Let the English upper-case (capital) letter

when juxtaposed to

indicate radiation at wavelengths longer than those of radiation that emanates from atomic

to those just above the extreme

.

	TRUE
	FALSE

	catching a beam
	one more degree of freedom than can be measured or controlled
	it may appear as a dome over a small portion of the Earth your standing on
	impervious to some traveling rays
	a secondary-object hazard

	possible orbits
	a charged particle wind
	gravity
	near the barycenter its system
	swirls of tan, green, blue, and white in the liquid methane
	electric arcs
	chlorophyll-containing phytoplankton aloft in an upper atmosphere

Any of many

in which something is related to something else by an equation of the form f(x) = a·x^k is called a

.

	TRUE
	FALSE

The emissivity of a perfect

equals 0, that of a perfect black body equals

.

	TRUE
	FALSE

A surface's spectral

and

do not depend on wavelength [for a graybody], so that the emissivity is a

.

	TRUE
	FALSE

The Oort cloud is a hypothesized

cloud of

which may lie roughly

, or nearly a light-year, from the Sun.

	TRUE
	FALSE

At the same time, in late

, there was a dramatic drop in collisions with

, which are thought to originate from the

.

	TRUE
	FALSE

	an outflowing wind
	particles into the pulsar
	particles from the pulsar
	electrons and positrons in the wind
	particles coming out of the pulsar very close to light speed

Some neutrinos originating from the Sun may be produced by the

reactions occurring in and above the

. Differentiating these coronal cloud-induced neutrinos from the neutrino background and those theorized to be produced within the

of the Sun may someday be possible with neutrino astronomy.

	TRUE
	FALSE

According to

relativity, c is the maximum speed at which all

,

, and

in the universe can travel.

	TRUE
	FALSE

	outward speed of the solar wind diminishes to zero
	inward pressure from interstellar space is compacting the magnetic field
	the solar wind even blows back at us
	a 100-fold increase in the intensity of high-energy electrons from elsewhere in the galaxy diffuse into our solar system from outside
	the source of heat that brings the coronal cloud near the Sun hot enough to emit X-rays may be the photosphere

The cosmic microwave background radiation is a

glow that fills the

in the

part of the

.

	TRUE
	FALSE

	susceptibility
	a material inert to change
	physical changes from radiation
	chemical changes by radiation
	radiation induced change to a material

Like gases,

lack fixed

structure; the effects of

is therefore mainly limited to

.

	TRUE
	FALSE

	the Earth becomes a monopole
	basalts record reversals
	seafloor magnetic anomalies
	reversals in ocean sediment cores
	reversals appear to occur at random intervals

	the longer the period for reversal the longer the surface irradiation
	the ionosphere seems to reach the surface
	life-forms may suffer from radiation sickness
	asteroids may strike the Earth that otherwise would not
	the rotation of the Earth slows to a halt
	poles of ice completely melt

DEBRA contains

over ~

decades of

from ~

eV to ~

GeV.

	TRUE
	FALSE

	antimatter signatures
	atmospheric origin
	TGFs occur about 50 times per day globally
	gamma radiation fountains downward from high cloud-top sources
	higher energy gamma rays than come from the Sun

Regarding a blue haze layer near the south polar region of Titan, the difference in color

above and

nearer the

could be due to

of the haze.

	TRUE
	FALSE

	antimatter signatures
	atmospheric origin
	X-ray flashes occur at least 50 times per day globally
	X-radiation fountains upward from low cloud-top sources
	as high or higher energy X-rays as come from the Sun

The swirls of tan, green, blue, and white are most likely

in the water. Some of the color may come from

.

	TRUE
	FALSE

	light elements may have been formed by the irradiation of interstellar matter
	closely matches the solar abundance
	not diminished by nucleosynthesis
	not destroyed by nuclear fission reactions
	may have been produced by cosmic-ray spallation

	may have been consumed by nucleosynthesis
	star formation in a cloud deficient in hydrogen
	may point away from a stellar association
	may have been formed by white dwarf mergers
	may have had transfer of helium from the secondary to the primary
	a possible massive convective event

One of the reasons why detection of

is controversial is that although

(and some other methods like rotational spectroscopy) are good for the identification of simple species with large dipole moments, they are less sensitive to more

molecules, even something relatively small like

.

	TRUE
	FALSE

	a spherical collection of stars
	moves together but unbound by gravity
	orbits a galactic core
	bound by gravity
	relatively high stellar density towards its center
	may have formed together

By comparing astronomical observations with laboratory measurements, astrochemists can infer the

abundances,

, and

of stars and interstellar clouds.

	TRUE
	FALSE

Theoretical astrohistory concerns

,

, and experimental facts with respect to observations in the past of the

of Earth.

	TRUE
	FALSE

	repulsive force
	repulsive ejection
	auroral-like phenomenon around the Sun
	rays and streamers
	centrifugal ejection of particles from the solar limb
	coronal discharges

The materials science of observatories involves the use of

or

materials that allow greater flexibility in the construction and deployment of observatories on,

, and above rocky-object surfaces. The environment near the observatory can also be used to

observation.

Hypotheses

Questions leaning more on theoretical development may be better.

External links

	a core which emits neutrinos
	a solar wind which emanates out the polar coronal holes
	gravity
	the barycenter for the solar system
	polar coronal holes
	coronal clouds
	its position

	naturally present
	ionizing radiation
	a continuum
	in the environment
	a one-time occurrence

	possible orbits
	a hyperbolic orbit
	nuclear fusion at its core
	nuclear fusion in its ionosphere
	near the barycenter of its stellar system
	accretion
	electric arcs
	impact craters

	photons go in but they don't come out
	absorption
	a hole or entry much smaller than a cavity
	emissivity
	reflectance

	possible orbits
	a hyperbolic orbit
	nuclear fusion at its core
	nuclear fusion in its chromosphere
	near the barycenter of its planetary system
	accretion
	electric arcs
	impact craters
	radar signature

	size of the object
	interpretation of associated phenomena
	a hot bow-wave
	ion wind
	forming ahead of the meteor

	spacetime
	interpretation of associated phenomena
	a hot bow-wave
	a steady rise
	forming ahead of the meteor

	possible orbits
	a hyperbolic orbit
	nuclear fusion at a star's exposed core
	nuclear fusion in a star's chromosphere
	near the barycenter of its planetary system
	accretion
	electric arcs
	non-water ice
	cometary origin

	solar coronal clouds
	solar wind
	photosphere
	polar coronal holes
	coronal mass ejections

	gaseous pressure much less than atmospheric pressure
	similar to a laboratory vacuum
	free space
	imperfect vacuum
	partial vacuum

	fluctuations
	no photons
	no matter particles
	relative permittivity
	relative permeability

	fluctuations
	ionizing
	airborne
	biologically functional components of the human body
	a component of DNA

	harmful changes
	induced radioactivity
	proton activation
	photodisintegration
	transmutation of elements
	lead into gold

	redder color indices
	closer stars more affected
	color excess
	observed color index minus intrinsic color index
	red shift
	blue shift

	moving faster than 65 km/s
	closer stars more affected
	may point away from a stellar association
	comet-like appearance
	red shift
	blue shift

	a hyperbolic pass
	stellar association
	may point away from a stellar association
	eccentricity
	obliquity
	precession

	internal structure
	element composition
	distributions of plasma, gases, liquids, or solids
	landscape
	spheres
	approximate concentricity

	driven by current gradients
	neutral atoms
	closed tube loops
	twisted flux
	open field lines
	synchrotron radiation

	an origin
	singularity
	chaos
	aether
	local steady-state
	uncountability
	irrational numbers