Plasmas/Plasma objects/Coronal clouds/Quiz

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This image is taken in Hα of the Sun and above showing a cloud above a sunspot. Credit: Alan Friedman.

Coronal clouds is a lecture and an article about a specific astronomical entity, a type of plasma meteor. It is also a part of the department of astronomy course on the principles of radiation astronomy.

You are free to take this quiz based on coronal clouds at any time.

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Quiz[edit]

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

1

Yes or No, The Chamaeleon I cloud is a coronal cloud.

Yes
No

2

Which of the following are green radiation astronomy phenomena associated with the Sun?

the color of the upper rim as seen from Earth
an excess brightness at or near the edge of the Sun
the iron XIV green line
neutron emission
polar coronal holes
meteor emission
changes in the line-blanketing

3

The population of coronal loops can be directly linked with the?

4

Which of the following is a prominent feature associated with solar clouds?

coronal mass ejections
rotation
magnetic clouds
coronal clouds
plasma
magnetic field lines

5

True or False, Coronal loops project into the coronal cloud, through the transition region and the chromosphere.

TRUE
FALSE

6

Which of the following is not a characteristic of solar active regions?

lithium
nucleosynthesis
coronal clouds
spot central meridian passage
a surface coverage of at least 95%.

7

About one third of ejecta observed by satellites at Earth is composed of what?

8

True or False, Coronal clouds are irregular objects suspended in the corona with matter streaming out of them into nearby active regions.

TRUE
FALSE

9

Which of the following are X-radiation astronomy phenomena associated with the Sun?

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
temperatures at or above 1 MK

10

True or False, The Ca XV emission line is a yellow coronal line at 569.4 nm.

TRUE
FALSE

11

Which of the following are associated with X-radiation?

spans three decades in wavelength
spans three decades in frequency
spans three decades in energy
emitted by 26Al
coronal clouds
60 keV electromagnetic radiation
90 eV electromagnetic radiation
visually dark source

12

True or False, The Milky Way has its own coronal cloud.

TRUE
FALSE

13

Complete the text:

The photosphere of the Sun has an effective temperature of

yet its corona has an average temperature of

. The high temperature of the corona shows that it is heated by something other than direct

from the photosphere.

14

True or False, In a coronal cloud are magnetohydrodynamic plasma flux tubes along magnetic field lines.

TRUE
FALSE

15

Which of the following are X-ray astronomy phenomena that may be associated with the Sun?

coronal cloud
hot regions of 8–20 x 106 K
fluorescence of Jovian X-rays
lightning
X-rays from rings
collisions with the Jovian wind
soft X-ray emission
hard X-ray emission

16

True or False, The hot ionized medium (HIM) consists of a coronal cloud which emits X-rays.

TRUE
FALSE

17

Complete the text:

Discussion of the alternative hypothesis of cloud ejection from the equatorial layer of the Galaxy leads to the conclusion that the

halo must be highly

and that the coronal clouds are probably

regions.

18

True or False, 3C 295 is a galaxy cluster filled with a vast cloud of 50 MK gas and plasma.

TRUE
FALSE

19

Pick the following sources that are or are likely to contain a coronal cloud?

AGNs
gamma-ray source
dark nebula
lightning
X-ray source
molecular cloud
soft X-ray emission source
hard X-ray emission

20

True or False, Coronal clouds, type IIIg, form in space above a spot area and rain streamers upon it.

TRUE
FALSE

Hypotheses[edit]

Main source: Hypotheses
  1. Solar flares occur before coronal clouds.

See also[edit]

External links[edit]