Captions for photos in photo_album/hires. Photo titles are in bold
1) Symmetry #1- Queen Anne’s Lace….Many of the laws of physics are noted for
their mathematical beauty and simplicity. One of their outstanding characteristics
is their symmetry with respect to many mathematical operations. This gives rise
to some amazingly beautiful forms in our everyday world. This photo of Queen
Anne’s Lace demonstrates this property quite well. Although simple, the subtlety
of sub-structure is also apparent, and provides another layer for the image.
2) Symmetry #2- The Cas-A Supernova Remnant….The laws that govern the
microscopic world also govern the properties of the stars. Here is an image of
Cas-A, a star that exploded over 400 years ago, in a cataclysmic conflagration of
epic proportions. For a brief period, it outshone the entire Milky Way galaxy, of
which it is a part. The material in the star hurtles out of the center at speeds of
over 5,000 miles per second, and is so hot (over 10 million degrees) that it glows
in X-rays. This sensational photo was taken with NASA’s Chandra X-ray
Satellite, with an exposure time of one million seconds. Since our eyes cannot
“see” x-rays, you are free to “color” it in any fashion you choose. We call this
technique of viewing an image: “false color”. In this rendition, the red, green and
blue show the low, medium and high energy x-rays, respectively. (Credit:
NASA/CXC/GSFC/U.Hwang et al.)
3) Star Trails Toward the North Celestial Pole….Taken in Shenandoah National
Park over the course of several hours, the camera was pointing toward Polaris, the
North Star. As the Earth turns, each star describes a circle around the imaginary
axis of the Earth’s rotation. Can you tell how long the exposure was from the
fraction of the circle that each star completes?
4) Star Trails Toward the Celestial Equator…. Taken the same night as #3, but
with a camera pointing towards the equatorial region of the sky. Why do the stars
curve in different directions north and south of the celestial equator (which is the
imaginary line made by extending the Earth’s equator out into space)?
5) Rocket Launch from White Sands New Mexico….Before satellites became
commonplace astronomical observatories, much observational data were
acquired by means of sounding rockets that briefly soared over 100 miles above
the Earth’s surface. Day time launches were especially spectacular; the solid
fueled booster on this Aerobee rocket launched from White Sands Missile Range
in New Mexico made the camera carrying scientific payload rather like a 30 foot
long bullet, with a sensational roar as it climbed out of the tower.
6) By the Light of Mating Fireflies….I am convinced that there is a Ph. D. lurking
in this photograph. For 25 years, I had been unsuccessful in getting a photo of
fireflies; their light output is quite limited. Then, I chanced across a 5 acre field in
upstate NY in which thousands of fireflies seemed to be motionless. This 4 hour
exposure showed that they were NOT motionless, and also not isolated. Which is
brighter, the male or female? Why do some pairs move vertically, and some
horizontally?
7) The Diamond Ring, July, 1991….For less than one second just before and after
a total eclipse of the Sun, a bright shaft of photospheric sunlight shines past the
edge of the Moon, while the rest of the circle is faintly illuminated by the corona.
This gives rise to the Diamond Ring. This photo is one in a series of ten that
show the development of this beautiful and rare occurrence.
8) Totality, July, 1991….Mount Pinatubo erupted just before the total eclipse of
1991, stopping the trade winds dead in their tracks, and bringing unusually cloudy
weather to Kona, Hawaii. By some miracle, the clouds parted about 15 seconds
before totality was set to begin. You can see just how cloudy it was in this
photograph, with a tree and the Hualalai Volcano in the foreground.
9) The Night of the Comet, March 28, 1996….Comet Hyakutake was a rather
small comet, but because it got exceedingly close to the Earth, it was quite bright,
but only for one night. Also, because it was positioned in the sky very close to
the North Pole, a fairly long exposure (2 minutes) was possible without having the
head of the comet look unnatural. The night this photograph was taken, the
temperature was about -15 F in Prattsburgh, NY.
10) Leonid Fireball, 2001…..Every 33 years, we are usually treated to an intense
display of meteors in November. Known as the Leonids, because they appear to
come from the constellation of Leo, they are noted for intense fireballs, which
sometimes audibly explode in our atmosphere. The narrow streaks on the photo
are star trails, but the teardrop shaped feature was a sensational fireball, whose
optical train persisted for about 10 minutes. Visible on original prints, it may not
reproduce well on these copies, but look for this cloudlike structure drifting away
from the teardrop at about 8 o’clock..