Investigation 23 - Dark Matter APODs

Explain your reasoning

Why don’t we see hydrogen Balmer lines in the spectra of stars with temperatures of 3,200 K?   a. There is no hydrogen in stars this cool.   b. The stars are hot enough that most of the hydrogen is ionized and the atoms cannot absorb energy.   c. These stars are so cool that nearly all of the hydrogen atoms are in the ground state.   d. Stars of this temperature are too cool to produce an absorption spectrum.   e. Stars of this temperature are too hot to produce an absorption spectrum.

Pls answer number 9 thank you so much

How to calculate.

How does one go about question b?

Please please solve accurate please solve accurate and exact answers

Suppose a spectral line from an object in space was shifted from 5007.0 to 5100.0 Angstroms. What can we tell about this object? A) It is a star. B) It is very cold. C) It is blueshifted, hence coming towards us. D) Its radial velocity is positive, meaning it is moving away from us. E) It is a planet in a distant galaxy. F) It is an exoplanet.

H.M 1-What wavelength (in nanometers) is the peak intensity of the light coming from a star whose surface temperature is 11,000 Kelvin? (Note: This is about twice the temperature of our Sun's surface.) 2-Determine the surface temperature of a star whose maximum intensity is at 400nm.

Hubble’s Field of View. Large telescopes often have small fields of view. For example, the Hubble Space Telescope’s (HST’s) advanced camera has a field of view that is roughly square and about 0.06° on a side. a. Calculate the angular area of the HST’s field of view in square degrees. b. The angular area of the entire sky is about 41,250 square degrees. How many pictures would the HST have to take with its camera to obtain a complete picture of the entire sky?

. The Sun as seen from Earth has an apparent magnitude of -26 in the B-band.1. What is the Sun’s absolute magnitude (in the B-band)?2. What would its apparent magnitude be as seen from Jupiter? (Jupiter is approximately 5.2 AU from theSun.)3. At a certain distance d from a Star A, its apparent brightness is f. If we were to travel at a relativisticvelocity to a point in space which is 5 times further away, how much fainter would the star appear to us?(i.e. what fraction of its original apparent brightness would it now appear to us?)

1. The relative velocities of four stars are shown in the figure below with arrows. If an astronomer were to study the light from these four stars, in which star would the astronomer see greatest redshift of its light spectra? Hint: Think Doppler Effect A. star 1B. star 2C. star 3D. star 4

Number 3. identify the knowns, unknown(s), appropriate formula(s) then computation.

4. on the ONLY next page compare differences in and luminosity (more or Refer to the figure following questions. temperature (hotter or cooler) less luminous) as determined from the diagram. In other words, consider only what you know about relationships between temperature versus luminosity, diameter luminosity, or color versus temperature relationships. make NOT *IMPORTANT NOTE: DO stars' masses or stage of life answer. any versus reference to the for your as a reason a) WOLF 28 and PROCYON have roughly the same surface temperature. Which star is smaller in diameter? (Explain which property of the star supports your reasoning. Review directions above.) b) BETELGEUSE and SANDULEAK have about the same luminosity. Which star is larger in diameter? (Explain which property of the star supports your reasoning. Review directions above.) c) VEGA and ZZ CETI have about the same temperature. Which star is smaller in diameter? (Explain which property of the star supports your reasoning. Review…

A bright blue star is moving away from Earth. Which of the choices best completes the following statement describing the spectrum of this star? A(n) spectrum that is relative to an unmoving star. O A. absorption; redshifted O B. emission; redshifted O C. continuous; blueshifted D. continuous; redshifted O E. absorption; blueshifted

If a species evolved in order to see white tissues of the body, which wavelength do they have receptors for? *   A.) Gamma   B.) Infrared   C.) Ultraviolet   D.) X-ray   If a species evolved in order to see bones and metals, which wavelength do they have receptors for? *   A.) Gamma   B.) Infrared   C.) Ultraviolet   D.) X-ray

What is background absorption and background correction. How does the use of a continuum light source help with background correction?

Cosmic Microwave Background 8. The Cosmic Microwave Background (CMB) acts as a perfect black body whose energy spectrum(energy density per unit volume per unit frequency) is given by the expression : (image attached)

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Define the term photon. Then, state whether a photon of blue light or red light has higher energy and why. Be sure to include an equation.

H5.

Please answer correctly

Help with 7

Analyze the multi-wavelength images below and answer the few questions that follows up : 1. Where do you see the higher energy phenomena? What are they? Are they visible in any image? Why?2. Where are the young stars? What colour do they have? Are they visible in any image? Why?3. Where are the old stars? What colour do they have? Are they visible in any image? Why?

Astronomers are always seeking to build bigger, more powerful telescopes, which will allow them to study faint galaxies that are very far away. Which of the following is the main reason they're so obsessed with studying very distant galaxies? Group of answer choices Light traveled much faster during the early history of the universe, so we can study how the speed of light has changed through time. Very distant galaxies are more likely to contain planets than the Milky Way is, so we have a better chance of detecting life in those galaxies than we do in our own galaxy. Since the light from these galaxies took so long to reach us, we're seeing them as they were when the universe was very young. Strangely, distant galaxies are more like our Milky Way than the Milky Way's `neighbor' galaxies are, and astronomers would like to figure out why this is.