Stockton Astronomical Society
Valley Skies - February 2006 Issue
History corrected... and proudly dedicated.
It was a chilly, clear morning when close to fifty proud members of the Madeira family came together in Volcano, California on January 21st. From sundry parts of California, Nevada and Oregon, they came to participate in the dedication of a relocated and updated historical marker commemorating California's first astronomical observatory, built by George Madeira Jr. in 1860.
Also on hand were members of the Stockton Astronomical Society and the Sacramento Valley Astronomical Society, the two clubs that were instrumental in erecting the original marker in 1968, and that helped defray the cost of the new one.
Congratulations to Marshal Merriam, whose three years of research culminated in this grand gathering of family-some meeting for the first time-local history buffs, and astronomy enthusiasts. An excellent lunch at the St. George Hotel capped a memorable morning.
Following the unveiling, Jerry Hyatt spoke on behalf of the SAS. His eloquent remarks truly captured the spirit of the occasion:
"This monument that is unveiled today does much more than commemorate the pioneering efforts of George Madeira Jr. This monument helps us celebrate the spirit of amateur astronomy, the spirit that infected a young George Madeira, the spirit that fills us all with wonder when we gaze at the night sky.
No other science shares this great legacy of astronomy, this legacy of amateurs making substantial contributions to the field. Amateurs build telescopes and observatories. Amateurs discover comets, meteors, and asteroids. Amateurs make key observations of many objects and events. Amateurs design experiments for professional observatories, as well as for the many platforms we have in orbit about the Earth. Amateurs share the wonders of astronomy with as many people as they can so that they can infect those who haven't been exposed.
So when you see the title "amateur astronomer," you should realize that it means much more than someone with an interest in astronomy. It indicates participation in a human heritage that extends from prehistoric times to present times, and for as long as humankind seeks knowledge, beauty, and grace in the skies above.
Today, we honor George Madeira Jr., amateur astronomer.
We should also acknowledge the work of another amateur astronomer, Marshal Merriam. Marshal's dedication, persistence, and tenacity are responsible for moving mountains, or at least this monument, to this more accurate location.
Marshal, we are in your debt. George, it is a privilege to have learned about your life and work. Thank you.
Nicely done, Jerry!
...Trevor Atkinson
The 4th annual Desert Sunset Star Party will be held April 26-30, 2006. Please check details at our website http://www.chartmarker.com/sunset.htm
Registration is now open. Caballo Loco RV Ranch gives us a special camping rate for this group event. There is no star party fee this year but we will sell door prize tickets. The residents of Caballo Loco will also be serving breakfast ($3) and dinner ($5) on Saturday. We are located between Kitt Peak Observatory and Whipple Observatory, both excellent day trips.
Pat and Arleen Heimann
Chart Markers and More
In 2005, SAS members Monty and Deborah Shindler attended the Desert Sunset Star Party (near
Tucson, AZ) and had a "wonderful time." The photo at right shows Monty at the EOS
Technologies facility, one of the daytime tours offered as part of the five-day annual event.
Call the Shindlers [see newsletter for phone number] if you'd like more feedback from members
who have made the trip.
Madeira Monument Event in Volcano
Unveiling of the plaque was by Muriel Thebaut and Norma Madeira Morgan. (Muriel Thebaut was responsible for first bringing forth the idea that a monument to George Madeira and the first astronomical observatory in California should be put up in Volcano. Her talk before the Sacramento Valley Astronomical Society in the early 1950's inspired Victor Killick, though he didn't acknowledge her role. Norma Madeira Morgan is the oldest living direct descendant of George Madeira, daughter of Jesse, grand-daughter of Frank, great-granddaughter of George Madeira. She was 89 at the time of the ceremony, so I've been told.
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Norma Madeira Morgan (right) with sister Ann Madeira Kately and Norma's husband H. H. Morgan (family historian). |
The dedication event took place in Volcano, Amador County, California on 21 January 2006.
Madeira Family present numbered 47+ (there were 47 paid lunches from the family, + a few small children who didn't pay). This number includes spouses and friends, so the number of descendants was smaller. There were four great-grandchildren of George Madeira present. They were: Harrison Truitt Starr, whose grandmother Mary Mitchell Madeira, oldest child of George Madeira, was born in Volcano in 1860; George William Madeira, whose grandfather was William R. Madeira, fifth child of George Madeira; and two great-granddaughters descended from Francisco Doria Madeira (known as 'Frank'), the seventh child of George Madeira. They are also the daughters of Jesse G. Madeira who participated in the 1968 ceremony. They are Norma Madeira Morgan and Ann Madeira Kateley.
Family attending came from Oregon, Nevada and various parts of California.
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Muriel Thebaut, Norma Madeira Morgan and Marshal Merriam prepare for the unveiling. |
Just some of the Madeira family attending the dedication! |
Astronomical Societies with members attending were SAS, SVAS, AAS (Amador Astronomical Society), and MDAS (Mount Diablo Astronomical Society). Also there were two persons attending from Lick Observatory (unofficially).
Speakers at the unveiling were: David Scharlach (Sacramento Valley Astronomical Society), Jerry Hyatt (Stockton Astronomical Society), Harrison Truitt Starr (descendant, see above).
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In Armory Hall
before the dedication, Marshal Merriam reviewed the life of George Madeira and issues found
in researching the new monument location.
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Harrison Truitt Starr spoke on behalf of the Madeira family. |
Monument sponsors (i.e., those whose contributions paid for it) were: the two astronomical societies (SAS and SVAS), several of the descendants of George Madeira, other individuals (including Marshal...ed,). Official sponsor of the project and the event was the Amador County Historical Society. This was an ACHS project to commemorate the 150th year ('Sesquicentennial') of Amador County. (When the Madeira family arrived in 1852, Volcano was part of Calaveras County and Amador County did not yet exist.)
Total attendance was 130, estimated by counting empty chairs.
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Main Street, Volcano - population 102. St George Hotel at far end. |
SAS group, from
left: Trevor Atkinson, Emelia Seiferling, Rosemary Atkinson, Jim Seiferling, Mary &
Jerry Hyatt, Marshal & Diane, Bev & Jack Sales; Lloyd and Judy Altamirano are out
of picture on the right.
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George David Madeira was born on 14 October 1836 in Galena, Illinois and died 21 January 1922 in San Francisco. He was cremated and what happened to the ashes isn't known (at least not to me).
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Norma Madeira Morgan and Muriel Thebaut. |
Ann Madeira Kately, Norma Madeira Morgan and Jerry Hyatt. |
This being the 84th anniversary of his death, the program was, in part, a commemoration of the life of George David Madeira, with special emphasis on the portion of his life he spent in Volcano.
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Marshal Merriam, Muriel Thebaut and Jerry Hyatt |
Press coverage (before the event) included a page-1 story in the Stockton Record on 19 January and a feature story on the first page of an interior section of the Ledger-Dispatch of Jackson, Amador County, on 11 January. There were also various short announcements on other dates.
...Marshal F. Merriam
27 January 2006
Except as noted, photos by Trevor Atkinson
Webcentric photos courtesy Barbara Kreiss of AAS
Snowstorm on Pluto
by Dr. Tony Phillips
There's a nip in the air. Outside it's beginning to snow, the first fall of winter. A few delicate flakes tumble from the sky, innocently enough, but this is no mere flurry.
Soon the air is choked with snow, falling so fast and hard it seems to pull the sky down with it. Indeed, that's what happens. Weeks later when the storm finally ends the entire atmosphere is gone. Every molecule of air on your planet has frozen and fallen to the ground.
That was a snowstorm-on Pluto.
Once every year on Pluto (1 Pluto-year = 248 Earth-years), around the beginning of winter, it gets so cold that the atmosphere freezes. Air on Pluto is made mainly of nitrogen with a smattering of methane and other compounds. When the temperature dips to about 32 K (-240 C), these molecules crystallize and the atmosphere comes down.
"The collapse can happen quite suddenly," says Alan Stern of the Southwest Research Institute. "Snow begins to fall, the surface reflects more sunlight, forcing quicker cooling, accelerating the snowfall. It can all be over in a few weeks or months."
Researchers believe this will happen sometime during the next 10 to 20 years. Pluto is receding from the warmth of the Sun, carried outward by its 25% elliptical orbit. Winter is coming.
So is New Horizons. Stern is lead scientist for the robotic probe, which left Earth in January bound for Pluto. In 2015 New Horizons will become the first spacecraft to visit that distant planet. The question is, will it arrive before the snowstorm?
"We hope so," says Stern. The spacecraft is bristling with instruments designed to study Pluto's atmosphere and surface. "But we can't study the atmosphere if it's not there." Furthermore, a layer of snow on the ground ("probably a few centimeters deep," estimates Stern) could hide the underlying surface from New Horizon's remote sensors.
Stern isn't too concerned: "Pluto's atmosphere was discovered in 1988 when astronomers watched the planet pass in front of a distant star-a stellar occultation." The star, instead of vanishing abruptly at Pluto's solid edge, faded slowly. Pluto was "fuzzy;" it had air. "Similar occultations observed since then (most recently in 2002) reveal no sign of [impending] collapse," says Stern. On the contrary, the atmosphere appears to be expanding, puffed up by lingering heat from Pluto's waning summer.
Nevertheless, it's a good thing New Horizons is fast, hurtling toward Pluto at 30,000 mph. Winter. New Horizons. Only one can be first. The race is on....
Find out more about the New Horizons mission at http://pluto.jhuapl.edu . Kids can learn amazing facts about Pluto at spaceplace.nasa.gov/en/kids/pluto.
This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
The following, forwarded by Jeff Baldwin, is from the Kingston RASC Astro Notes newsletter:
What we say:
Yes, the premium apo refractors are well worth the money.
What we mean:
(A) My spouse has no idea what I spend on astro gear,
or
(B) We have no children in our household.
What we say:
Well, yes, with a little work that Tasco you have can make a decent starter scope.
What we mean:
I feel your pain.
What we say:
I live in a moderately light polluted area.
What we mean:
I'm about ready to go on a rampage and shoot out all the street and flood lights within 10
miles.
What we say:
If you dress properly, cold weather observing is no problem.
What we mean:
I haven't lost any fingers or toes to frostbite yet.
What we say:
This small apo gives the ultimate razor sharp, high contrast views.
What we mean:
I'm not industrious enough to set up a big dob, but this thing sure was expensive - aren't
you impressed?
What we say:
Yes, it takes a few minutes to get set up, but the views through this big daddy dob are
unbelievable.
What we mean:
This behemoth has finally worn me down. Wanna buy it?
What we say:
I can't quite make out the spiral arms in that galaxy.
What we mean:
Where's the galaxy? My night vision died ten years ago.
Seeing Geostationary Satellites
Objects that orbit the Earth above its equator orbit faster if they are close and slower if they are far. This is Kepler's Third Law in action. Kepler's Third Law says that the average distance of an orbiting object cubed is related to the time it takes to orbit squared. If a satellite orbits close to the Earth, it takes roughly an hour and a half to orbit, while a satellite farther from the Earth, such as the Moon, takes nearly a month to orbit the Earth. Somewhere between an hour and a half and a month is 24 hours, or 1 day. If a satellite is just the right distance away from the Earth, it will take 1 day to orbit. So as the Earth turns, taking 1 day, the satellite will also orbit, taking 1 day, and therefore appear over the same location over the equator as they turn in synchronization. So, how far would a satellite have to be from the Earth to make this magic happen?
The Moon averages about 239,000 miles from the center of the Earth, and it takes an average
of 27.3217 days to orbit (29.5306 days between phases). Let's call 239,000 miles 1 Lunar
Unit, and 27.3217 days 1 Sidereal Month. Let's start closer than a geostationary satellite,
in fact, let's start with a low-orbiting satellite, say, 100 miles above the Earth's surface.
The Earth's (equatorial) radius is 3978 miles, so a satellite 100 miles high would orbit the
center of the Earth from a distance of 4078 miles. That works out to
Lunar Units, or 0.01706 L.U. If we cube this we
get about 0.000004965, which would be the square of the time it takes to orbit according to
Kepler's Third Law. The square root of 0.000004965 is 0.002228 Sidereal Months. That
multiplied by 27.3217 is 0.06088 days, and multiplied by 24 is 1.4611 hours, or about 1 hour
and 28 minutes (our hour and a half). So, the Mercury capsules took about an hour and a
half to orbit the Earth. Cool. Now let's get around to a geostationary satellite.
We want to know the distance of an orbit that takes 23 hours 56 minutes 4 seconds (1 sidereal day) to orbit the Earth. 23 hours 56 minutes 4 seconds is equal to 23.9345 hours, which is equal to 0.99727 days, or 0.0365 Sidereal Months. That number squared is 0.001332. The cube root of that is 0.11004 Lunar Units. 0.11004 times 239,000 miles is 26,300 miles from the center of the Earth, which works out to abut 22,300 miles above the surface of the Earth at the equator. So, geostationary satellites orbit the Earth from an altitude of about 22,300 miles. At that distance the satellite will orbit the Earth in the same period of time that the Earth rotates, keeping that satellite directly above the same location all the time. You can now point a satellite dish in the direction of that satellite and never have to worry about it drifting from alignment.
If you are at a certain latitude, what will be the elevation of a geostationary satellite orbiting at your longitude? In figure 1 the geostationary satellite is to the right of the Earth, the observer is at latitude θ, the angle upward from the celestial equator that the satellite looks up toward the observer is Φ, and the Earth's radius, r, is 3978.
The height of the triangles is r sin θ, or 3978 sin θ,
and the base of the triangle on the left is 26,300-3978 cos θ. □ would then be
equal to 
.
The third angle of this triangle (upper right vertex) would be 90°-Φ, and the angle
above the horizon you would have to look to see the satellite would be the complement of your
latitude minus Φ. That's too much junk, so if you want to get within about a degree,
then let 
,
and the altitude of the geostationary satellite orbiting on your longitude will be the
complement of your latitude minus Φ. Let's try Stockton, CA. Stockton's latitude is
about 38°, so its complement is 52°.
,
about 6°. So 52°-6° is about 46°. For Beaver, WA, it would work out to
about 42°-8° is about 34°, much lower.
Is there a place on Earth that a geostationary satellite can't see? Or put in another way, are there locations on Earth that can't see geostationary satellites? Yes. In Figure 2 you can see that the tangent line from the geostationary satellite to the Earth does not allow the pole to see the satellite since it would be under the horizon. In fact some region below the pole can't see them.
The right triangle on the left has an hypotenuse of 26,300 miles, and the radius of the Earth
is the short leg, and it is 3978 miles. The angle
=8.7°. The angle
α=90-β, which is 81.3°. That means that the highest latitude
that can see a geostationary satellite from the Earth's surface is 81° 18' north
latitude, and an equal issue exists at the equivalent south latitude.
If you'd like to photograph geostationary satellites, put some high speed film in your SLR camera and set it on a tripod with a fairly wide-angle lens, and point it southward so that the celestial equator runs along the middle of the view frame. Expose some 1 hour (or so) exposures with the f-stop wide open. You will get star trails as the Earth turns, but you will get a few geostationary satellites in the photograph about 6° south of the celestial equator because they don't seem to be moving. They will be right and left of each other forming a line (circle seen from near the center) around the Earth. If I do this up here in Washington, they will be about 8° south of the celestial equator. It would be slick if we did this on the same night at the same time and compared the exposures.
Hope this was interesting and accurate, clear skies all!
...JBald
Copyright © 2006 by Stockton Astronomical Society
Last Updated: 2/14/2006
http://astro.sci.uop.edu/~sas/Newsletter/VS0602.html
