We look toward a cool star. How can we determine that there is an interstellar dust cloud between us and the star?
What will be an ideal response?
The temperature of the star is determined by spectral type and photometrically using the B and V filters. If there is no intervening dust then the two temperature determinations will agree. If there is dust, the photometrically determined temperature will appear lower than the temperature indicated by the spectral type because the starlight has been reddened. Dust cannot affect the spectral type.
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Why does the Sun brighten with time?
A) as time progresses, helium starts to fuse in the core, in addition to hydrogen, leading to an increase in brightness B) as hydrogen is converted into helium in the core, the number of hydrogen nuclei decreases, decreasing the fusion rate. To maintain the balance with gravity pressing inward, the core compensates by shrinking and heating up C) as time progresses, more and more heat is trapped inside the core, leading to an increase in brightness D) as hydrogen is converted into helium in the core, the number of hydrogen nuclei decreases, decreasing the fusion rate. To maintain the balance with gravity pressing inward, the core compensates by expanding and cooling
To determine gauge pressure, add the atmospheric pressure to the absolute pressure
Indicate whether the statement is true or false
What is a magnetosphere?
A) the uppermost layer of any planetary atmosphere B) the layer of a planet in which its magnetic field is generated C) the region in a planet's atmosphere in which auroras occur D) a region of space around a planet in which the planet's magnetic field can trap charged particles
What is the composite volcano shape?
What will be an ideal response?