Infrared stars is a lecture from the department of radiation astronomy possibly for the course on the principles of radiation astronomy and is already in the star courses.

Combined observations from NASA's Spitzer Space Telescope and the newly completed Atacama Large Millimeter/submillimeter Array (ALMA) in Chile have revealed the throes of stellar birth, as never before, in the well-studied object known as HH 46/47. Credit: NASA/JPL-Caltech/ALMA.

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Quiz edit


1 The Sun may be a first astronomical source of?

blue rays
cyan rays
infrared rays

2 Yes or No, HR 4731, α2 Cru is an infrared source in the constellation Crux.


3 Imaging brown dwarfs involve which of the following:

far-infrared (submillimeter) observations at 350 microns
neutrino detection
heating of the nearby gas and dust
near-infrared covering 1.3 and 2.2 microns
infrared covering 4.5 and 8.0 microns

4 Which of the following are radiation astronomy phenomena usually associated with lithium emission?

a green emission line
an orange line at 610.3 nm
the Spite plateau
lithium-drifted silicon detectors
the Fraunhofer E line
asymptotic supergiant branch
an infrared line at 812.6 nm

5 True or False, In 1926 there were no national observatories (except the Naval Observatory), very little chance for guest observing elsewhere, no radio astronomy, no X-ray astronomy, no satellite astronomy, and very little infrared or even red astronomy!


6 Complete the text:

Astronomers place the submillimetre waveband between the


wavebands, typically taken to be between a few hundred micrometres and a millimetre.

7 True or False, The Earth's atmosphere does not transmit infrared radiation between 6 and 7 microns in wavelength because of water vapor.


8 Complete the text:

Match up the radiation letter with each of the detector possibilities below:
Meteors - A
Cosmic rays - B
Neutrons - C
Protons - D
Electrons - E
Positrons - F
Neutrinos - G
Muons - H
Gamma rays - I
X-rays - J
Ultraviolet rays - K
Optical rays - L
Visual rays - M
Violet rays - N
Blue rays - O
Cyan rays - P
Green rays - Q
Yellow rays - R
Orange rays - S
Red rays - T
Infrared rays - U
Submillimeter rays - V
Radio rays - W
Superluminal rays - X
multialkali (Na-K-Sb-Cs) photocathode materials


511 keV gamma-ray peak


broad-band filter centered at 404 nm

a cloud chamber

ring-imaging Cherenkov


effective area is larger by 104



a blemish about 8,000 km long

a metal-mesh achromatic half-wave plate

coated with lithium fluoride over aluminum

thallium bromide (TlBr) crystals


aluminum nitride

heavy water

18 micrometers FWHM at 490 nm

wide-gap II-VI semiconductor ZnO doped with Co2+ (Zn1-xCoxO)

a recoiling nucleus

high-purity germanium

magnetic deflection to separate out incoming ions

2.2-kilogauss magnet used to sweep out electrons


9 Complete the text:

Match up the item letter with each of the possibilities below:
superluminals - A
radios - B
radars - C
microwaves - D
submillimeters - E
infrareds - F
reds - G
oranges - H
deuterium enrichment of cometary water

interstellar-comet connection

a macroscopic superstring

force of life

rings of Saturn

volcanic activity throughout Vesta

a silicon composite bolometer fed by a Winston cone

present-day fluctuations an order of magnitude larger


10 Complete the text:

Match up the radiation type with the satellite:
meteor - A
cosmic ray - B
neutral atoms - C
neutron - D
proton - E
electron - F
positron - G
neutrino - H
gamma ray - I
X-ray - J
ultraviolet - K
optical - L
visual - M
violet - N
blue - O
cyan - P
green - Q
yellow - R
orange - S
red - T
infrared - U
submillimeter - V
microwave - W
radio - X
radar - Y
superluminal - Z



























11 Complete the text:

Methane possesses prominent

in the visible and near-infrared (IR) making

aquamarine or

in color.

12 Which of the following are phenomena usually associated with fluorine emission?

fluorine emission lines in the green are relatively weak
fluorine lines in the near infrared are usually much stronger than the green lines
F I has lines in the green
F II has lines in the green
F III has at least one line in the green
the Fraunhofer E line

13 True or False, The European Space Agency's Herschel Space Observatory has aboard the Photodetector Array Camera and Spectrometer (PACS) which operates in three bands centred on 70, 100, and 160 μm, respectively.


14 The Spitzer Space Telescope has the following phenomena usually associated with it?

85 cm diameter
lightweight boron
3 - 180 µm wavelength range
the Fraunhofer E line

15 Radiation phenomena associated with trigonometric parallax are

gamma-ray trigonometric parallax distances < 0.4 kpc
X-ray trigonometric parallax distances good to 2 pc
ultraviolet trigonometric parallax is good to ± 7 pc
visual trigonometric parallax distances good to about 3 kpc
infrared trigonometric parallax with an accuracy of 120 µas
radio trigonometric parallax distances good at least to 1.86 kpc

Hypotheses edit

  1. Questions about infrared stars can touch on any and all wavelengths.

See also edit

External links edit

{{Radiation astronomy resources}}