Why are interstellar lines so narrow?
Q: An astronomer is observing a binary star that is 15 pc away. The two stars have an orbital…
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Q: If interstellar dust makes an RR Lyrae variable star look 7 magnitudes fainter than the star should,…
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Q: If a prostellar disk is 260 au in radius and the disk plus the forming star together contain 7 solar…
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Q: What would most bright nebulae look like if there were no interstellar dust?
A: A nebula is defined as a large region of interstellar clouds made of dust, hydrogen, helium, and…
Q: What is the orbital speed at the disk's outer edge in kilometers per second if a protostellar disk…
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Q: The dust in a molecular cloud has a temperature of about 34 K. At what wavelength (in nm) does it…
A: temperature = T = 34 K wavelength = λmax=?
Q: If you assume that a globular cluster 2 arc minutes in diameter is actually 27 pc in diameter, how…
A: The expression for the distance from small angle formula, Angular diameter206265=linear…
Q: What are the approximate spectral type, temperature, absolute magnitude number, and luminosity of…
A: Required : Spectral type, absolute magnitude, temperature and luminosity of star E.
Q: A typical dense core of an interstellar gas cloud has a diameter of 0.2 pc and a mass of 2 solar…
A: The diameter of the gas cloud is defined as 0.2 pc. Therefore, the radius of the gas cloud will be…
Q: Star A has a temperature of 3000K; Star B has a temperature of 5000K; Star C has a temperature of…
A: Given value--- temperature of star A = 3000 K. temperature of star B = 5000 K. Temperature of…
Q: If interstellar dust makes an RR Lyrae variable star look 2 magnitudes fainter than the star should,…
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Q: If a globular cluster contains 1 million stars and is 25 pc in diameter, what is the average…
A: The diameter of the globular cluster is d= 25 pc. Number of stars contain by the open clusters n= 1…
Q: If you assume that a globular cluster 6 arc minutes in diameter is actually 18 pc In diameter, how…
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Q: If a galaxy has an apparent radial velocity of 4000 km/s and the Hubble constant is 70 km/s/Mpc, how…
A: Hubble's law states that galaxies move away from Earth with a velocity proportional to their…
Q: If interstellar dust makes an RR Lyrae variable star look 5 magnitude fainter than the star should,…
A: Given the magnitude get fainter by 5. Therefore,
Q: Now, rank the same objects by increasing temperature. For spherical objects, use the surface…
A: Intercloud gas: The gases other than intersteller gases present in space are known as intercloud…
Q: The very first "image" of a black hole, at the centre of galaxy M87, was recently taken by the Event…
A: Given: The wavelength of the hydrogen line is λ = 21 cm The diameter of the earth is D = 12742 km…
Q: How is the turnoff point on the H-R diagram of a cluster related to the cluster’s age?
A: Given:- The turnoff point on the H-R diagram of a cluster related to the cluster’s age Explain:- How…
Q: Why massive stars are short lived?
A: A massive star has a shorter life spanthan an average star because of fasterhydrogen fuel…
Q: If a globular cluster contains 2 million stars and is 28 pc in diameter, what is the average…
A: This problem can be solved by first calculating the average volume reserved for one star and then…
Q: Consider two different clusters with approximately the same turnoff luminosity. Cluster A has a main…
A: Given two clusters A and B on the H-R diagram (which is a plot between the luminosity and…
Q: Why must astronomers use infrared telescopes to observe the motions of stars around Sgr A*?
A: There is dust in the interstellar medium made of molecules and elements send out from the surface of…
Q: If the hottest star in the Carina Nebula has a surface temperature of 51,000 K, at what wavelength…
A: Concept: "The Wien's displacement law states that the wavelength carrying maximum energy is…
Q: What is hydrostatic equilibrium in stars.
A: The interstellar medium is mostly made of hydrogen. When the mass of the interstellar medium becomes…
Q: If an open cluster contains 450 stars and is 21 pc in diameter, what is the average distance between…
A: Given Number of stars in an open cluster (n) = 450 Diameter of the cluster Dclu = 21 pc…
Q: you assume that a globular cluster 4 arc minutes in diameter is actually 27 pc in diameter, how far…
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Q: A two-arm spiral density wave is moving through the Galactic disk. At the 8-kpc radius of the Sun's…
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Q: If a galaxy has an apparent radial velocity of 2,319 km/s and the Hubble constant is 70 km/s/Mpc,…
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Q: Hotter, more massive stars are virtually absent from globular clusters. What does this tell us?…
A: Globular clusters are clusters of stars, that are nearly symmetrical and round shaped clusters.…
Q: describe the characteristics of the various kinds of interstellar gas (HII regions, neutral hydrogen…
A: Star formation is generally more active in the denser, inner part of the Milky Way than in the outer…
Q: What temperature would interstellar dust have to have to radiate most strongly at 100 micro meter?
A: When stars die they will slowly send out their outer layers. This forms large clouds of dust and is…
Q: describe how the 21-cm line of hydrogen is formed. Why is this line such an important tool for…
A: In space almost all of the hydrogen atoms are in ground state. The electron moves around the proton…
Q: The RR Lyrae stars in a globular cluster have apparent magnitudes of 14. Assuming an absolute visual…
A: Given that the apparent magnitude mv=14 and the absolute visual magnitude Mv=0.5, substituting…
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- (a) Rank the following components of the interstellar medium in order of the wavelengths at which they are observed, longest wavelength first: clouds of neutral hydrogen, coronal gas, interstellar dust, nebulae. Longest to Shortest? (b) Rank the same material in order of decreasing temperature from hottest to coolest. Hottest to Coolest?If an open cluster contains 650 stars and is 27 pc in diameter, what is the average distance between the stars? (Hint: On average, what share of the volume of the cluster surrounds each star?)If a galaxy has an apparent radial velocity of 2000 km/s and the Hubble constant is 70 km/s/Mpc, how far away is the galaxy?
- Suppose you observe a star orbiting the galactic center at a speed of 1500 km/skm/s in a circular orbit with a radius of 24 light-days. Calculate the mass of the object that the star is orbiting.if a protostellar disk is 260 au in radius and the disk plus the forming star together contain 7 solar masses what is the orbital speed at the outer edge of the disk in km per second. use the circular orbital velocity formulaWhat evidence can you cite that the interstellar medium contains both gas and dust? (Select all that apply.) (1)The dust of the interstellar medium can be detected from the emission lines of elements heavier than iron. (2)The dust of the interstellar medium can be detected by the extinction of light from distant stars. (3)The dust of the interstellar medium can be detected by the scattering of blue light from distant or embedded objects. (4)The gas of the interstellar medium can be detected from the radiation of ultraviolet photons. (5)The gas of the interstellar medium can be detected from the radiation of photons of wavelength 21 cm. (6)The gas of the interstellar medium can be detected from the absorption lines present in the light from distant stars, which must be caused by a medium of a density and temperature other than that of the stars emitting the light.
- Which of these colors of light passes most easily through interstellar clouds? a Green light b Red light c Blue light d Violet lightFigure 2 shows the "rotation curve" of NGC 2742. It plots the “radial velocity (V)" (how fast material is moving either toward or away from us) that is measured for objects at different distances (R = radius") from the center of the galaxy. The center of the galaxy is at 0 kpc (kiloparsecs) with a speed of 9 km/sec away from us. (These velocities have been corrected for the observed tilt of the galaxy and represent true orbital velocities of the stars and gas.) 200 100 U4779 -100 As you can see, one side of the galaxy is moving with a negative velocity (spinning toward us), while the other side has a positive velocity (spinning away from us). Using Newton's gravity equation, we will be able to determine the gravitational mass of the entire galaxy and how the mass varies versus distance from the galaxy's center. -200 -8 8 -4 Radius (kpc) Read the following text carefully and follow the instructions: Select five radii spaced evenly from 0-10 kpc across the galaxy. Your selections should…The hydrogen Balmer line has a wavelength of 486.1 nm. It is shifted to 565 nm in a galaxy's spectrum. What is the radial velocity (in km/s) of the galaxy? (Indicate the direction with the sign of your answer.)