Page 10, 1st column, line 7
The actual relative brightnesses of Betelgeuse and Rigel depend
both on time (since Betelgeuse is a variable star) and
wavelength. Betelgeuse is an M2 supergiant with a color of
B-V=1.85, and Rigel is a B8 supergiant with a color of B-V=-0.03.
Therefore, given that the current magnitudes of Betelgeuse and
Rigel are V=0.44 and V=0.12, making Betelgeuse slightly dimmer than
Rigel, a slight shift of the wavelength band redward of V would make
Betelgeuse quite a bit brighter than Rigel. In this course we will
consider Betelgeuse as being the brighter of the two stars.
Pages 103 to 104, section on Light-Gathering Power
The discussion applies only to a point source object, or to an
unresolved source. For real objects, the diameter of the image
must be taken into account. Since longer focal length telescopes
produce larger images, the surface brightness of an image depends of the
square of the ratio of telescope diameter to focal length, or
inversely on the square of the focal ratio. It is true however that
the total amount of light in the image depends on the square of the
Page 148, 1st column, section on Earth's density
Page 193, 2nd column, section on Mercury's density
Notice that the earth's density is given as 5.5 g cm-3 and
Mercury's is given as 5.43 g cm-3, 0.98 that of Earth, yet
Figure 8.25 shows that Mercury's core is proportionally bigger.
Any comparison of terrestrial planets' density must only be done on
the uncompressed density. Since Earth's uncompressed density is
4.2 g cm-3, Figure 8.25 does actually make sense. Disregard
the factor of 0.98 for density comparison.
Page 195, Figure 8.24
This figure tries to combine information on density
(crust, mantle, and core) with information on rigidity
(lithosphere and asthenosphere) in the Moon. The figure is not truly
successful in this endeavor however; two separate figures would have
been a better choice. Recall that the thickness of the
crust is 60 (nearside) to 100 (farside) km, the thickness of the
mantle 1200 km, and the
radius of the core, 400 to 500 km. The thickness of the lithosphere is
1000 km, and the asthenosphere is the outer 500 km of the inner
700 km radius sphere.
Page 209, Figure 9.A
At latitude=63, longitude=336, change
"Secojawea" to Sacajawea".
Page 218, 1st column, line 7 from bottom
Change "half" to "70 percent".
Page 227, Interlude 10-1
The first person to use the term canali for Mars
was the Italian astronomer Angelo Secchi in 1869.
Page 292, 2nd column, line 10
The statement about the temperature at which ammonia freezes into ice
crystals is in conflict with Figure 11.6 (page 248) which shows the
temperature of the ammonia ice clouds in Jupiter's atmosphere. The
temperature given on page 292 is wrong; the temperature is closer to
125 K. Methane however freezes at a temperature of about 70 K. Also
delete the sentence following this one. Ammonia is not seen in the
atmosphere of Uranus and Neptune because it forms clouds deeper down
(below the methane clouds) and is obscured. On Jupiter, ammonia forms
clouds high in the atmpshere (above all the other clouds) and is readily
observed in its gaseous state.
Page 294, Figure 13.9
The magnetic polarity of every planet is just the opposite of what is
indicated. That is, each instance of "N" should be replaced by
Page 363, 1st column, line 10
Change "above the" to "above the base of the".
Page 363, Caption for Figure 16.13
Change "outer edge" to "inner edge".
Page 363, Figure 16.13
Change the X axis label from "Distance above photosphere
(km)" to "Distance above base of photosphere (km)".
Shift the pink section marked Chromosphere to run from 500 km
to about 7000 km. The photosphere runs from 0 to 500 km, and
spicules in the chromosphere can reach to 7000 km.
Page 388, Figure 17.11
The temperatures given in the figure are not consistent with
the positions of the peaks of the curves. The actual temperatures are
close to 19,500 K, 4,420 K, and 2500 K. The figure attempts
to show that for a 10,000 K star, the B and V intensities
are equal. However they are not equal; it is the B and
V magnitudes that are equal and only because of a hidden
scaling factor that cannot be shown in the figure. Ignore
Page 434, 1st column, line 15 from bottom
Change "Figure 18.20" to "Figure 18.19".
Page 476, Figure 21.7
The light curve for Type II supernova should be shifted so that its peak
intensity lies below that of the curve for Type I.
Page 479, 1st column, line 5 from bottom
Note that except in a psychological sense, we cannot be overdue
for events that are truly
random, i.e., where the probability doesn't vary with time.
For events where the probability increases with time, e.g. an
earthquake fault whose stress is building up, or a particular
massive star whose core has been accumulating heavy elements for
some time, the
idea of being overdue could apply.
Page 480, 2nd column, line 7 from bottom
The element Technetium does in fact occur naturally on Earth. It was
discovered in 1925 in columbite ore by Ida Tacke and her colleagues in
Germany. It can also be found in Uranium ore.
Page 488, Figure 21.17
The half lives given in the figure are wrong. For Nickel-56
it should be 6.1 days, and for Cobalt-56 it should be 77 days.
Page 508, 2nd column, line 7 from bottom
Change "574" per century" to "5600" per century".
Page 526, 1st column, line 12 from bottom
Page 529, 1st column, line 9 from bottom
The sun's distance from the center of the Galaxy, although
not known exactly, was given a working value of 8.5 kpc by
the International Astronomical Union in 1982.
Page 626, Figure 27.1
The figure contains some errors. The radiation density and the
matter density do decrease at different rates as time increases,
however in a log-log plot the relations are straight lines only when
the horizontal axis is the "scale size", R, of the universe. If the
axis is time, as in the figure, then the slopes of the relations
change at the crossover from radiation-dominated to matter-dominated,
creating knees in the curves. Interestingly, for a Euclidean
universe, the slope of the radiation density in the
radiation-dominated region matches the slope of the matter density
in the matter-dominated region.
Page 629, Table 27.1
Change Density of 3X1025 to 3X10-25
Page 636, 1st column line 12
Change "Grand Unified Terories" to "Grand Unified Theories"
Page 637, Figure 27.12
Change "(a) Time = 10-39s" to "(a) Time = 10-35s"
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