DopplerShift:TheHb(hydrogenbeta)line,whichisstronginthespectraof
moderately hot stars, has a wavelength of 486.133 nm in the
laboratory (i.e., at rest with respect to the observer). What
wavelength (nm) would we observe the Hb line on Earth if it were
emitted by a star:
a) moving at a speed of 200 km/s toward Earth?
b) moving at a speed of 300 km/s away from Earth?
As the source approaches the wave length decreases, and it increases when the source goes away
DopplerShift:TheHb(hydrogenbeta)line,whichisstronginthespectraof moderately hot stars, has a wavelength of 486.133 nm in the laboratory (i.e., at rest...
(a) At what wavelength will we observe a spectral line emitted at 500 nm by a star (b) At what wavelength will we observe the Ca II line (with rest wavelength 397.0 (c) A cloud of neutral hydrogen (HI) emits the so-called "21-cm line" (actually moving toward us at 100 km/s? nm) emitted by a galaxy receding at 60,000 km/s? 21.11 cm, at rest frequency 1420.2 MHz) while moving away at 200 km/s. At what frequency will we observe this...
6 1. A red photon has a wavelength of 660 nm. How fast must a star be moving toward the Earth for a red photon emitted by the star to change its color to an orange photon of wavelength 620 nm? You may, if you wish, express your answer either in m/s or in terms of the speed of light c (e.g., "0.021c"). [You'll need to do a little bit of algebra. Keep in mind that, by convention, the velocity...
A star has an emission line at a wavelength of 666.80 nm. The rest wavelength of the line is 656.3 nm. What is the velocity of the star? Hint: How does the velocity of a star depend on its observed wavelength? What is the equation for Doppler shift? The speed of light is 3.0 × 105 km/s.
The H α transition in hydrogen has a rest wavelength of 656.3 nm, coming from electrons moving between the n=2 and n=3 orbitals. You observe a star in which this transition shows a wavelength of 650 nm. How fast is the star moving? Is it moving toward you or away from you. Calculate the same for a galaxy where the wavelength of H α is 1100 nm.
Astronomy Ranking Task: Doppler Shift Exercise #4 Description: An important line in the absorption spectrum of stars occurs at a wavelength of 656nm for stars at rest. Imagine that you study five stars (A-E) from Earth and discover that this absorption line is observed at the wavelength shown in the table below for each of the five stars. STAR Observed Wavelength of Absorption line A 650 nm B 663 nm C 656 nm D 657 nm E 646 nm...
Suppose that you observe a spectral line in a star at a wavelength of 600.06 nm. Knowing that the same spectral line has a laboratory wavelength of 600.00 nm, what is the velocity of the star along the line of sight (in km/s)
One of the visible lines of hydrogen has a rest wavelength of 656.285 nm, but it appears in the spectrum of the star Vega at 656.255 nm. How is Vega moving relative to us( toward or away)? Calculate with what speed. Show work.
Astronomers determine that a nearby galaxy is moving toward our galaxy at a speed of 723.0 km/s with respect to the Earth. If Earth receives a wavelength λ = 679.1 nm from a particular star in this nearby galaxy, what was the wavelength emitted by the star? (Give your answer to at least three significant figures.)
Need help with this problem. Thanks. Binary Stars Q1) A binary star system has a distance from Earth of 42.2 light years. The distance between the stars is 1.08 x 101 m and the rotation period is 104 days. Assume equal masses of the stars, and circular orbits (centre of mass of the system is at rest relative to the Earth). a) Calculate the speed of the stars relative to the centre of mass of the system. Further assume the...
A line in a star's spectrum lies at 400.0 nanometers. In the laboratory, that same line lies at 400.3 nanometers. How fast is the star moving along the line of sight? Is it moving toward or away from us? The speed of the star is ______km/s.