Astronomy for Teachers, 1st session: 6 November 2006
I'll be filling in some notes from the first meeting session here. The
links to all the original sources for the images should all be there, and
correct. If any of them do not work, please let me know. I will try to
post links to my rescaled images, though it may take a bit.
Show and tell
Theme: "Sometimes, there are surprises."
- Mauna Kea - JCMT,
Submillimeter array assembly building, CSO, Subaru, UH 0.6-meter, Keck 1,
Keck 2, UKIRT, IRTF, UKIRT, UH 2.2-meter, Gemini, and CFHT.
- Arecibo - 300m diameter radio dish in
Puerto Rico.
- SALT - 11m South African Large
telescope, the largest in the southern hemisphere. First light in November 2005.
- Swift telescope - a new
gammaray and x-ray telescope designed to help find the astronomical
objects that produce gammaray bursts: some of the largest explosions in
the universe.
- Surprise:
Earthrise from Apollo 8 in orbit. It took them just under 4 days to get there.
- Earth
and Moon from Galileo, 1990. Note the size and brightness differences (the
moon was artifically brightened to bring out detail!), as well as which
side is illuminated.
- SOHO prominence
and magnetic field structure from best of SOHO. Emission in this spectral
line shows the upper chromosphere at a temperature of about 60,000 degrees
K. Every feature in the image traces magnetic field structure. The hottest
areas appear almost white, while the darker red areas indicate cooler
temperatures.
- Surprise: Solar flare
strikes SOHO. 5 November 1998 from best of SOHO. Protons
accelerated to 10% the speed of light arrived at SOHO in about an hour,
causing numerous bright points and streaks in the last two images.
- Spirit
rover at the top of `Husband Hill'' in the Columbia Hills
on Mars, just after reaching the summit in August 2005.
- Thin rings
around Saturn with Enceladus, taken in polarized infrared.
- Surprise:
ring ripples. Prometheus and Pandora (not in frame) maintain
the outer F ring, Pan (20km across, visible) maintains the Encke gap
and its ringlet with ripples.
- M56
from Lynch Observatory. Globular cluster, ~33,000ly distance, 85ly
across, several hundred thousand stars.
- Surprise: SDSS funny double star (white-dwarf, red giant) with strange
spectrum. No link, but if you want to see the data, please e-mail me!
- Ring nebula.
A famous planetary nebula. The blue gass is Hot and the gas cools as you
look further out in the ring, red being the coolest. ~1ly across, 2000ly distant.
- Surprise:
McNiel's nebula, part of the Orion complex. Young star outburst
lit the surrounding gas. It was discovered by an amateur observer in
Kentucky.
- Crab
nebula, x-ray: pulsar and hot gas (wrong scale - too large), visual:
synchrotron electrons and hydrogen gas, IR: warm dust, Radio: free electrons.
- Surprise:
SGR1806-20 as observed by Integral Dec 27. 2004 (a Russian
satellite saw the reflection of the signal from the moon, 12 other satellites
also saw it, some while not even looking in the correct direction).
- Multiwavelength
Milkyway. The galaxy we live in, as observed in a variety of
wavelengths.
- Surprise:
new SDSS dwarf merger. Should be symmetric top/bottom, dotted line is
Sagittarius dwarf. Press release today!
- Andromeda.
The closest large galaxy near us. Very similar to our own Milkyway.
- Tadpole
Galaxy - Arp 188. Distance 420 million ly, Tail length is roughly
280,000ly. This galaxy was disrupted by an interloper that passed through
a few million years ago. The long tail is the gas that was pulled off,
which will eventually form into its own small galaxy.
- Abell
1689 taken in 2002 by ACS. Surprise: look at the arcs: the cluster of
galaxies in the center is acting like a fun-house mirror, and distorting
the light from the background galaxies. Prof. Dave Goldberg studies the
shapes of those arcs to determine how much mass is causing the bending of
the image.
- Hubble
ultra-deep field. 11.3 days total exposure time. Every dot that
doesn't have diffraction spikes is a galaxy: there are thousands in the
image, and it is a very small fraction of the sky.
- Surprise: Cosmic
Microwave Background (CMB) from the WMAP satellite.
Penzias and Wilson discovered the CMB in 1963 and won the Nobel Prize for
their discovery.
- Surprise:
Family portrait from Voyager 1. The Voyager I spacecraft took this
picture on its way out of the solar system. Earth's image is refered to
as the "Pale Blue Dot."
Carl Sagan's quote about
that last image, given at a commencement address. For more from Dr. Sagan
on that theme, as well as a generally uplifting and interesting book on
Astronomy, see Pale Blue Dot: A Vision of the Human Future in Space. There
are two versions, one with illustrations and one without. Make certain you
get the version with illustrations, as they are a large part of what makes
the book so great.