ASTRONOMY 101 EXAM 2
From the article "What Are Celestial Coordinates," why is Right Ascension
measured in hours instead of degrees?
The benefit of this numbering system is that as the earth rotates, you see the sky
turn by about 1 hour of RA for each hour of time. This makes it easy to find when
celestial objects come in and out of view.
From the article "What Are Celestial Coordinates," on the sky, what reference
point does the line of 0 hours of Right Ascension pass through?
The reference point is where the ecliptic line crosses the celestial equator in
Prices.
From the article "What Are Celestial Coordinates," describe how precession
affects the celestial coordinates of Polaris, what we currently call our North Star.
In precession, the moving celestial poles drag the whole celestial coordinate
system (the whole grid of declination and right ascension) along with them.
From "Echoes, Chapter 2:" What (modern) constellation is associated with the
"stretching of the cord" ceremony in ancient Egypt. Describe the evidence that
leads astronomers to making this association.
The Big Dipper.
,They came to this association because a priest touched the mouth of a deceased
pharaoh, in which to receive life, this symbolized the big dipper
From "Echoes, Chapter 2:" What is the purpose of the "stretching of the cord"
ceremony in ancient Egypt? What is it analogous to in today's society?
The ritual required the pharaoh to establish the basic reference line for the
temple's orientation and plan, he studied a star's position and movement to
create this reference point.
-Today, a there is a · standardized technique for accurately surveying in a direction
reference line. This means there was a tradition of astronomical observation to
back it up.
From "Echoes, Chapter 2:" In the study of the Cahokia Sun Circle, explain the
significance of the discovery of a posthole offset 5 feet due east from the central
posthole of the circle.
The locations of many poles were offset because if you take the alignment from
the center of the circle they are off. This offset must be corrected.
From "Echoes, Chapter 2:" By comparing the Cahokia circle to similar circles
found in Virginia and Florida, the author makes an argument for and against the
hypothesis that the Cahokia Sun Circle was mainly used for astronomical
purposes. Describe the evidence and how it supports or detracts from the
astronomical hypothesis.
, The rings of the Virginia and Florida Indians include no central post, Cahokia's
does.
-The sun circle's offset central post appears to be deliberately placed and favors
the astronomical alignments.
From "Echoes, Chapter 2:" Many different alignments for the windows are
proposed in the passage about the Caracol in Chichen Itza, including the setting
sun on the equinox, the extreme northern and southern moonsets, the extreme
northern and southern setting locations of Venus and even the setting of the
Pleiades. Why does the author argue that the equinox alignment of the largest
window (window 1) is likely not an accurate interpretation?
The measurements of the "moonset alignments" showed they missed the moon
by more than 2 degrees, and, in fact, the northernmost moonset is not even
visible through window 1, so the due south line was 3 degrees off
-The author argues that Venus may have been intended because it is the 3rd
brightest object in the sky
From "Echoes, Chapter 2:" Why does the author argue (two reasons) that the
most likely alignment, if one exists at all, is to the extreme northern and
southern setting locations of Venus?
Venus is the third brightest object in the sky.
-It's settings reach extremes on the horizon similar to the sun's.
-The moon set alignment fit the Venus extreme and their moonset alignments
show they missed the moon by more than 2 degrees.
From the article "What Are Celestial Coordinates," why is Right Ascension
measured in hours instead of degrees?
The benefit of this numbering system is that as the earth rotates, you see the sky
turn by about 1 hour of RA for each hour of time. This makes it easy to find when
celestial objects come in and out of view.
From the article "What Are Celestial Coordinates," on the sky, what reference
point does the line of 0 hours of Right Ascension pass through?
The reference point is where the ecliptic line crosses the celestial equator in
Prices.
From the article "What Are Celestial Coordinates," describe how precession
affects the celestial coordinates of Polaris, what we currently call our North Star.
In precession, the moving celestial poles drag the whole celestial coordinate
system (the whole grid of declination and right ascension) along with them.
From "Echoes, Chapter 2:" What (modern) constellation is associated with the
"stretching of the cord" ceremony in ancient Egypt. Describe the evidence that
leads astronomers to making this association.
The Big Dipper.
,They came to this association because a priest touched the mouth of a deceased
pharaoh, in which to receive life, this symbolized the big dipper
From "Echoes, Chapter 2:" What is the purpose of the "stretching of the cord"
ceremony in ancient Egypt? What is it analogous to in today's society?
The ritual required the pharaoh to establish the basic reference line for the
temple's orientation and plan, he studied a star's position and movement to
create this reference point.
-Today, a there is a · standardized technique for accurately surveying in a direction
reference line. This means there was a tradition of astronomical observation to
back it up.
From "Echoes, Chapter 2:" In the study of the Cahokia Sun Circle, explain the
significance of the discovery of a posthole offset 5 feet due east from the central
posthole of the circle.
The locations of many poles were offset because if you take the alignment from
the center of the circle they are off. This offset must be corrected.
From "Echoes, Chapter 2:" By comparing the Cahokia circle to similar circles
found in Virginia and Florida, the author makes an argument for and against the
hypothesis that the Cahokia Sun Circle was mainly used for astronomical
purposes. Describe the evidence and how it supports or detracts from the
astronomical hypothesis.
, The rings of the Virginia and Florida Indians include no central post, Cahokia's
does.
-The sun circle's offset central post appears to be deliberately placed and favors
the astronomical alignments.
From "Echoes, Chapter 2:" Many different alignments for the windows are
proposed in the passage about the Caracol in Chichen Itza, including the setting
sun on the equinox, the extreme northern and southern moonsets, the extreme
northern and southern setting locations of Venus and even the setting of the
Pleiades. Why does the author argue that the equinox alignment of the largest
window (window 1) is likely not an accurate interpretation?
The measurements of the "moonset alignments" showed they missed the moon
by more than 2 degrees, and, in fact, the northernmost moonset is not even
visible through window 1, so the due south line was 3 degrees off
-The author argues that Venus may have been intended because it is the 3rd
brightest object in the sky
From "Echoes, Chapter 2:" Why does the author argue (two reasons) that the
most likely alignment, if one exists at all, is to the extreme northern and
southern setting locations of Venus?
Venus is the third brightest object in the sky.
-It's settings reach extremes on the horizon similar to the sun's.
-The moon set alignment fit the Venus extreme and their moonset alignments
show they missed the moon by more than 2 degrees.
