1.3 Redshift Assignment

OBSERVE: Which of the spectrums (B or C) illustrate red-shift? How do you know?

CONCLUDE: What does the red-shift of this star's spectrum tell you about the direction it is moving?

EXPLAIN: What is happening to the wavelength of starlight that causes the red-shift?

OBSERVE: Which spectrum is shifted to the left? What type of shift is this -- blue-shift or red-shift?

CONCLUDE: Which spectrum is that of a star moving toward Earth? How do you know?

In the image of each spectrum to the left, the middle section shows

the observed galactic spectrum. The star in each spectrum indicates

the hydrogen line -- the part that scientists can study to determine

the motion of the galaxy.

The first spectrum represents hydrogen as it is located in laboratory

settings. Use this first star as your comparison point.

The galaxies have been listed in order from the closest (NGC 4473)

to the farthest (Galaxy in the Gemini Cluster).

CRITICAL THINKING: Spectrum B and Spectrum C are moving in opposite directions at different speeds. Which star is moving FASTER? How do you know? Explain your answer fully.

In the image of each spectrum to the left, the middle section shows

the observed galactic spectrum. The star in each spectrum indicates

the hydrogen line -- the part that scientists can study to determine

the motion of the galaxy.

The first spectrum represents hydrogen as it is located in laboratory

settings. Use this first star as your comparison point.

The galaxies have been listed in order from the closest (NGC 4473)

to the farthest (Galaxy in the Gemini Cluster).

OBSERVE: What pattern do you notice in the movement of the hydrogen line in each spectrum?

In the image of each spectrum to the left, the middle section shows

the observed galactic spectrum. The star in each spectrum indicates

the hydrogen line -- the part that scientists can study to determine

the motion of the galaxy.

The first spectrum represents hydrogen as it is located in laboratory

settings. Use this first star as your comparison point.

The galaxies have been listed in order from the closest (NGC 4473)

to the farthest (Galaxy in the Gemini Cluster).

CONCLUDE: On the visible light spectrum, blue wavelengths are the shortest (left side), and red wavelengths are the longest (right side). Which galaxy's light has been "red-shifted" the most? Explain your reasoning.

In the image of each spectrum to the left, the middle section shows

the observed galactic spectrum. The star in each spectrum indicates

the hydrogen line -- the part that scientists can study to determine

the motion of the galaxy.

The first spectrum represents hydrogen as it is located in laboratory

settings. Use this first star as your comparison point.

The galaxies have been listed in order from the closest (NGC 4473)

to the farthest (Galaxy in the Gemini Cluster).

INFER: When wavelengths have been stretched, we call this red-shifted. When wavelengths have been pushed together, we call this blue-shifted. Based on the spectra you see above, what can you infer about the movement of each of the galaxies?

In the image of each spectrum to the left, the middle section shows

the observed galactic spectrum. The star in each spectrum indicates

the hydrogen line -- the part that scientists can study to determine

the motion of the galaxy.

The first spectrum represents hydrogen as it is located in laboratory

settings. Use this first star as your comparison point.

The galaxies have been listed in order from the closest (NGC 4473)

to the farthest (Galaxy in the Gemini Cluster).

USE EVIDENCE: How does the red-shift of light from galaxies support the big bang theory? Explain fully.