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Tag Archives: astronomy

Our OnStep re-build is at last working!

05 Thursday May 2022

Posted by gfbrandenburg in astronomy, Hopewell Observatorry, Telescope Making

≈ 1 Comment

Tags

astronomy, ATM, ealing, Hopewell Observatory, OnStep, stepper motor, Telescope, Telescope Making, testing

For many months, we members of The Hopewell Observatory have been doing our best to repair the 50 year-old clock drive on our university-grade Ealing telescope mount.

Yesterday, after a lot of help from others, I finally got it to work — at least in the day time. With no telescopes mounted on it. And 100% cloud cover. So I really don’t know for sure.

We still need to test it out on a clear night, to see how well it tracks and finds targets.

I think I will re-configure the wiring so that it fits in a box outside the mount, instead of using the weirdly-shaped compartments inside: one needs to do occasional maintenance on the OnStep hardware and software, and none of that is easy to access right now.

A short video is attached.

Disturbing Racist Clauses Found in Early NCA Constitutions & Bylaws

29 Wednesday Sep 2021

Posted by gfbrandenburg in astronomy, History, science, Telescope Making

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Tags

Albert Einstein, amateur, astronomy, Black people, by-laws, Carnegie Institution of Washington, Caucasian, CIW, constitution, DC, ERO, Eugenics, Eugenics Records Office, Fairfax, George Carruthers, High Schools, History, Hitler, Montgomery County, National Capital Astronomer, Nazis, NCA, Prince George's County, Racism, science, Segregation, Star Dust, Washington

By Guy Brandenburg

Recently, while preparing to give a talk at this year’s Stellafane telescope-makers’ convention, I was disappointed to discover that the National Capital Astronomers (NCA), which I’ve belonged to for about 30 years, specifically excluded Black members for nearly 3 decades: from about 1940 all the way up to1969.

But NCA didn’t start out being overtly racist. Our original 1937 founding document has no such language. It reads, in part,

“The particular business and objects of [the NCA] shall be the education and mutual improvement of its members in the science of Astronomy and the encouragement of an interest in this science among others. (…) The activities of this Association are designed for the enjoyment and cultural profit of all interested in astronomy, whether the member be a beginner, an advanced student, or one whose pursuit of the science is necessarily desultory.”

And today’s NCA home page reads, “All are welcome to join. Everyone who looks up to the sky with wonder is an astronomer and welcomed by NCA. You do not have to own a telescope, but if you do own one that is fine, too. You do not have to be deeply knowledgeable in astronomy, but if you are knowledgeable in astronomy that is fine, too. You do not have to have a degree, but if you do that is fine, too. WE ARE THE MOST DIVERSE local ASTRONOMY CLUB anywhere. Come to our meetings and you will find this out. WE REALLY MEAN THIS!”

But in the 1940’s, the original open-minded and scientific NCA membership policy changed. The January 1946 Star Dust listed a number of changes to be voted on by the membership in the club’s founding documents. (See https://capitalastronomers.org/SD_year/1946/StarDust_1946_01.pdf ) The organization voted to change article III of its constitution as follows:

From:

“only Caucasians over 16 years old are eligible for membership.”

To this:

“to include all ages (see by-laws), exclude only the Black race.”

While it may be shocking that a scientific organization like NCA had such a policy, people often forget how racist a nation the USA used to be, and for how long. If you look up actual pages of DC area newspapers from the 1950s, you will note that the classified advertisements were largely segregated both by race and by gender – want ads would very often specify male or female, single or married, White-only or Colored-only jobs, apartments, and so on.

Schools in DC, MD, and Virginia were mostly segregated, either by law or in practice, up until the late 1960s or early 1970s. The 1954 Brown v Board decision had very little real impact in most areas until much, much later. Queens (NYC), PG County (MD) and Boston (MA) had violent movements against integrating schools in the 1970s. I know because I attended demonstrations against those racists and have some scars to prove it.

While the Federal and DC governments offices were integrated immediately after the Civil War, that changed for the worse when Woodrow Wilson was elected President in 1912.

Many scientists in the USA and in Europe believed the pseudo-scientific ideas of racial superiority and eugenics that arose around 1900 and were still widespread 50 years ago – and even today, as recent events have sadly shown.

In The War Against the Weak: Eugenics and America’s Campaign to Create a Master Race, Edwin Black explains how august scientific institutions like the Carnegie Institution of Washington (CIW), the American Natural History Museum in New York, and a number of eminent statisticians and biologists for many decades supported the Eugenics Records Office (ERO) at Cold Spring Harbor. So did the fabulously wealthy Rockefeller and Harriman Foundations.

The ERO pushed the concept of the genetic superiority of the ‘Nordic’ race and helped to pass State laws sterilizing the ‘weak’ and forbidding interracial marriage. They were also successful in passing the 1924 Federal immigration law that severely cut back immigration from parts of the world where supposedly ‘inferior’ people lived – e.g. Eastern and Southern Europe. As a result, many Jews who would have loved to escape Hitler’s ovens by crossing the Atlantic never made it.  

Hitler and his acolytes always acknowledged their ideological and procedural debt to American eugenical laws, literature, and propaganda. As we all know, Germany’s Nazis put those ideas to work murdering millions of Jews, Gypsies, Slavs and others.

It took more than three decades for the CIW to withdraw their support of the ERO. A CIW committee concluded in 1935 “that the Eugenics Record Office was a worthless endeavor from top to bottom, yielding no real data, and that eugenics itself was not a science but rather a social propaganda campaign with no discernable value to the science of either genetics or human heredity.” (Black, p. 390) The members pointedly compared the work of the ERO to the excesses of Nazi Germany. However, it took four more years for CIW to cut all their ties – shortly after Hitler invaded Poland in 1939, starting World War Two.

I don’t know exactly when the ‘Caucasian’-only policy became part of the NCA rules, but it seems to have been between the club founding in 1937, and October 1943 when volume 1, number 1 of Star Dust was printed. At one point, perhaps around 1940, NCA decided that only ‘Caucasians’ over 16 could join. But as indicated above, in 1946, the racial exclusion policy was narrowed to only exclude Black people. Apparently Jews, Italians, young people, Latin Americans, and Asians were eligible to join NCA from 1946 to 1969. But not African-Americans.

While researching my talk, I found that the NCA held amateur telescope-making classes at a number of all-white DC, MD, and VA high schools, from the 1940s through about 1970, both during the days of de jure segregation and the merely de-facto type: McKinley, Roosevelt, Central, Bladensburg, Falls Church, and McLean high schools are listed. While Star Dust mentions a telescope-making course at (the largely-Black) Howard University in 1946, there is no mention of any assistance for that course from NCA.

I also found no evidence in any issue of Star Dust from that era that anybody at the time raised any vocal objections to racial exclusion. Not in 1946, nor 23 years later when the rule prohibiting Black members was quietly dropped (in 1969) when a new constitution was adopted.

A few current or past NCA members confirmed to me that at some point, they noticed that racist language and privately wondered about it. One person told me that they definitely recalled some now-deceased NCA members who were openly racist and not shy about expressing those views. Others told me that they had never heard any discussion of the subject at all.

 (As one who grew up in DC and Montgomery County, and attended essentially-segregated public schools there, I am sorry that neither I nor my family actively spoke up at the time, even though a farm adjacent to ours in Clarksburg was owned by a Black family [with no school-age children at the time]. Amazing how blind one can be! The racists of those days were not shy about committing violence to achieve their ends. Fear might be one reason for silence.)

One possibility is that some of the early NCA meetings might have been held at private residences; perhaps some of the racist members insisted in preventing non-‘Caucasian’ or ‘Black’ people from attending. It is too bad the other NCA members didn’t take the other route and stay true to the original ideas of the club, and tell the racist members to get lost.

Very ironic: the late George Carruthers, a celebrated Naval Research Labs and NASA scientist, and an instrument-maker for numerous astronomical probes and satellites, gave a talk to the NCA in September of 1970 – not too long after the NCA apparently dropped its racist membership rules (April, 1969). So, a mere year and a half before he gave his talk, he could not have legally joined the organization. Nor could he have done so when he was making his own telescopes from scratch as a teenager in the 1940s. See https://en.wikipedia.org/wiki/George_Robert_Carruthers on the life and work of this great African-American scientist and inventor.

To NCA’s credit, we have done better in the past few decades at encouraging participation in telescope viewing parties, telescope making, and lectures by members of all races and ethnic groups. However, I often find that not very many NCA members bring telescopes to viewing events, or show up to judge science fairs, in mostly-minority neighborhoods. Often, it’s just me. That needs to change. We need to encourage an interest in science, astronomy, and the universe in children and the public no matter their skin color or national origin, and we need to combat the racist twaddle that passes for eugenics.

I anticipate that NCA will have a formal vote repudiating the club’s former unscientific and racist policies and behavior. I hope we will redouble our efforts to promote the study of astronomy to members of all ethnic groups, especially those historically under-represented in science.

We could do well to note the words that Albert Einstein wrote in 1946, after he had been living in the US for a decade, and the same year that NCA confirmed that Black people could not join:

“a somber point in the social outlook of Americans. Their sense of equality and human dignity is mainly limited to men of white skins. Even among these there are prejudices of which I as a Jew am clearly conscious; but they are unimportant in comparison with the attitude of the “Whites” toward their fellow-citizens of darker complexion, particularly toward Negroes.

The more I feel an American, the more this situation pains me. I can escape the feeling of complicity in it only by speaking out.

Many a sincere person will answer: “Our attitude towards Negroes is the result of unfavorable experiences which we have had by living side by side with Negroes in this country. They are not our equals in intelligence, sense of responsibility, reliability.”

I am firmly convinced that whoever believes this suffers from a fatal misconception. Your ancestors dragged these black people from their homes by force; and in the white man’s quest for wealth and an easy life they have been ruthlessly suppressed and exploited, degraded into slavery. The modern prejudice against Negroes is the result of the desire to maintain this unworthy condition.

The ancient Greeks also had slaves. They were not Negroes but white men who had been taken captive in war. There could be no talk of racial differences. And yet Aristotle, one of the great Greek philosophers, declared slaves inferior beings who were justly subdued and deprived of their liberty. It is clear that he was enmeshed in a traditional prejudice from which, despite his extraordinary intellect, he could not free himself.

What, however, can the man of good will do to combat this deeply rooted prejudice? He must have the courage to set an example by word and deed, and must watch lest his children become influenced by this racial bias.

I do not believe there is a way in which this deeply entrenched evil can be quickly healed. But until this goal is reached there is no greater satisfaction for a just and well-meaning person than the knowledge that he has devoted his best energies to the service of the good cause.”

Source: http://www.kganu.net/sitebuildercontent/sitebuilderfiles/alberteinsteinonthenegroquestion-1946.pdf

I am indebted to Morgan Aronson, Nancy Byrd, Richard Byrd, Geoff Chester, Jeff Guerber, Jay Miller, Jeffrey Norman, Rachel Poe, Todd Supple, Wayne Warren, Elizabeth Warner, and Harold Williams for documents, memories, and/or technical support.

Easy ways to show the earth is not flat

18 Friday Dec 2020

Posted by gfbrandenburg in Uncategorized

≈ Leave a comment

Tags

astronomy, earth, flat, flat earth, foucault, Leon Foucault, mathematics, planet, solar system

Sharing Steve Ruis’ handy methods anybody can use to show that the earth is in fact round. Very clever!

An Open Letter to the Many Flat Earthers Now in Existence

by Steve Ruis

Dear Flat Earthers,
Many people have been derogatory of your belief that the Earth is flat. Please note that they are belittling your belief, not you per se. You, personally, are an idiot, but that is probably not your fault.

Here are any number of accessible approaches for discovering the shape of our beloved planet. Enjoy!

* * *

Use Your Phone!
On Christmas Day, here in Chicago, I expect there to be snow on the ground because, well, it is winter. On Christmas Day I can pick up my phone and dial up anyone in Australia and ask them “What season is it?” They will tell you that it is summer in Australia. You might want to ask your flat Earth mentors how it could be winter and summer simultaneously on a flat Earth.

Use Your Phone!
Go to a globe and pick a spot half way around the Earth (I know it is a false representation in your belief, but humor me.) In the middle of the day, phone somebody at or near that spot. Call a hotel, they are always open. Ask whoever responds “Is it light or dark outside?” They will tell you that it is dark where they are. You might want to ask your flat Earth mentors how it could be light and dark simultaneously on a flat Earth.

Look Up What Local Time Was
In the US there was this concept of “local time” which was that “noon” was when the sun was at its highest point in its arc. You could call up people on the telephone who were not that far away and ask them what time it was and they would tell you something different from what your clock was telling you. The farther away they were, the greater the difference would be. On a flat Earth the time would be the same everywhere.

Look Up What Time Zones Are
I am writing this in the central time zone in the U.S. These zones were created at the behest of the railroad industry whose dispatchers were going crazy making up schedules for trains when every place had their own times. By creating these “zones” everything would be exactly one hour off from those in neighboring zones, two hours off for the next over zones, and so on. If you don’t believe me . .  pick up your phone and dial up a friend who lives a considerable distance (east-west) away from you and ask them what time it is. The time they state will be a whole number of hours away from your time. Heck, even the NFL knows this. When I lived on the left coast, the games started at 10 AM and 1 PM. Now that I live in the central time zone, the games start at 12 Noon and 3 PM. Over New York way the games start at 1PM and 4 PM. Do you think those games are replayed in one hour increments? Nope, time zones!. You might want to ask your flat earth mentors how it could be that simultaneous games start at different times on a flat Earth.

Watch the Video
Astronauts in the International Space Station (ISS) have made continuous videos of an entire orbit of the Earth. It takes only about an hour and a half about the length of a typical Hollywood movie. During the whole movie the earth appears round, and yet it is clear that different continents are passing in our view.

Now you may argue that NASA made this movie as propaganda for the Round Earth Conspiracy. It is certainly within our CGI abilities at this point, but you may want to ask why NASA would want to do such a thing? Plus, many astronauts have taken their own cameras aboard and taken pictures for themselves and they show the same thing. How could the Round Earth Conspiracy have allowed that to happen? It must be incompetence! Conspiracies aren’t what they used to be!

Da Balloon, Boss, Da Balloon
Many amateurs, unaffiliated with the government, have launched rockets and balloons high up into the atmosphere to take pictures. Every damned one of those pictures shows that the Earth is round. How come all of those cameras ended up pointed at the curved edge of your round and flat disk Earth? Such a coincidence!

An Oldie But Goodie #1
Occasionally, during a lunar eclipse, you can see the shadow of the earth falling upon the Moon. The shadow is always circular. This would be true if the flat earth were always dead on to the Moon, but the Moon orbits the Earth and wouldn’t a flat Earth be edgewise, often as not, and wouldn’t that create a non-round shadow on the Moon? Inquiring minds want to know.

An Oldie But Goodie #2
It was claimed that one of the first demonstrations of the earth being round was the observation of ships sailing west from Europe/England could be observed for a while but the ship itself was lost to sight while the mast was still visible. This would not happen on a flat Earth. The whole ship would just get smaller and smaller as it sailed west.

For pity’s sake, I live 22 stories up and the shores of Lake Michigan and I cannot see anything directly opposite me in Michigan. All I can see is water, with any kind of magnification I can muster. And I am not looking across the widest part of this lake! If the earth were flat, the lake would be flat and I could see the Michigan shore.

And Finally . . .

All of the fricking satellites! Do the math. What kind of orbit is stable around a flat disk earth? Answer none! And there are hundreds of the danged things in orbit.

Also, just for giggles. Look up what a Foucault pendulum is, And explain its behavior based upon a flat Earth.

PS You may be getting good vibes in your special knowledge that you know something other people do not. However, would not that special feeling be more worthwhile were you to volunteer at a food bank or a day care center or senior center? Wouldn’t doing something worthwhile be more rewarding that making a statement about how those pointy-headed intellectuals aren’t so smart?

PPS I have seen the cute models with the Sun and Moon on sticks rotating around (see photo above). If that were the case, everyone could see the Sun and Moon all day, every day. (There is straight line access to both objects in that model from everywhere on the flat disk.) Do you see the Sun and Moon all day, every day? No? Maybe someone who had more creativity than knowledge came up with those models. They do sell well, I must admit, so maybe their interest is commercial.

PPPS Regarding the 200 foot wall of ice that supposedly exists at the “edge of the disk,” supposedly so all the water doesn’t flow off and be lost into space. By now don’t you think someone would have sailed next to that wall all of the way? That distance would be somewhere in the neighborhood of a 28,000 mile trip. Has anyone ever report such a thing? Hmm, I wonder why not

When was the last time you spent a night under the stars?

29 Wednesday Jun 2016

Posted by gfbrandenburg in astronomy, astrophysics, Hopewell Observatorry, Telescope Making

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Tags

astronomy, Hopewell Observatory, open house, Telescope

If it’s been a while since you spent time looking up at the heavens with your naked eyes, binoculars and telescopes, looking at planets, stars and galaxies, then this Saturday might be your night.

The Hopewell Observatory is having an open house on Saturday, July 2, 2016, and we have a variety of scopes to look through. Some of the scopes will be under our roll-off roof and some will be rolled out onto the small lawn outside the observatory itself.

Mars, Jupiter and Saturn will be very conveniently placed for viewing right at sundown, and if it’s dry and clear enough, we should be able to see the Milky Way. Many nebulae, open and globular clusters, galaxies, and double or triple stars will be visible as well.

You are invited!  And it’s free!

The location is about an hour due west of Washington DC by way of I-66, near the town of Haymarket, VA. For detailed directions, follow this link, which I posted for one of the dates which got canceled because of bad weather. Ignore the date, but do pay attention to the fact that we have no running water! We have bottled water and a composting toilet and hand sanitizer. Plus makings for coffee, tea, and hot chocolate – all gratis.

picture of hopewell

The picture above is of one of our telescope mounts, which carries several telescopes and was set up to take astrophotographs at the time. Below is a picture of the outside of the observatory shortly after a snowstorm.. Notice that there is no dome – instead, the galvanized steel roof rolls back on the rails and columns to the right of the picture when the scopes are in use.

showA13

If you have your own telescope, feel free to bring it. If it needs electricity, we have an outdoor 120VAC outlet, but you should bring your own extension cord and plug strip.  If you want to stay all night, that will be fine, too! If you feel like bringing a cot or a tarpaulin and a sleeping bag, that’s equally OK by us! Show up at or near sunset, and stay until the sun comes up, if you like!

Warning: the area definitely has insects, such as ticks and chiggers, which appear to avoid everybody else and to do their best to attack me. I strongly recommend long pants, shoes/boots, and socks that you can tuck the pants into. Tuck your shirt into your pants as well, and use bug spray, too. I have personally seen plenty of deer, cicadas, moths, wild turkeys, squirrels, and birds, and I have heard from a neighbor that a bear tried to eat his chickens, but other than the insect pests, the wildlife stays out of your way.

Again – for detailed directions, look at this link.

Great Long Weekend of Observing Near Spruce Knob, WVa at 11th Almost Heaven Star Party

18 Tuesday Aug 2015

Posted by gfbrandenburg in astronomy, Telescope Making

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Tags

AHSP, astronomy, ATM, dobsonian, star party

I put all of my tickets (over 30!) into the raffle for a 100-degree-apparent-field-of-view eyepiece at AHSP but didn’t win it. I probably should have put a few tickets in some other raffles. They had a whole lot of different stuff being raffled off. The eyepiece I wanted was donated by Hands On Optics. At AHSP they give you ten tickets as part of your registration, and then you can buy more of them. Elizabeth Warner and her husband left the morning of the raffle (Sunday) and gave me theirs, which was very nice of them.

At Stellafane, they used to have just ONE humongous item in the raffle, like a full set of really expensive eyepieces from Al Nagler. So it used to be in fact all-or-nothing. Don’t know if it was like that this year?
I discovered that the things I really needed were:
* an inexpensive laser collimator so I can get collimated in a minute or two all by myself, accurately, instead of fumbling around for an hour and needing an assistant… (now on order)
* an inexpensive electronic timer controller for my Canon TSi so it doesn’t need any cables to a computer (also now on order)
* a way to get rid of dew. The last night was fantastic except for the dew, which even defeated the chemical hand warmer packets that I wrapped around my finder and Telrad. I bet it got to the secondary as well. I will study up on the physics of heat production by resistors or heating wire wrapped around those and devise something.
BTW, I had to use a borrowed hack saw and masking tape to cut each of my truss tubes by exactly an inch on the second day so that I could come to a focus with all my eyepieces. I used some local rocks to deburr the cuts.
They had some great presentations on astrophotography, including how to do it simply and effectively. I was much encouraged.

Charon (NOT Pluto) with a huge crater that may have bashed it out of round

14 Tuesday Jul 2015

Posted by gfbrandenburg in astronomy, astrophysics

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Tags

astronomy, comet, crater, impact, minor planet, New Horizons, planet, pluto, solar system

Here’s a very recent (7-12-2015) picture of Pluto Charon that shows a bright circular feature near 1 o’clock with a long white streak heading down and to the right for a very long way – possibly even as much as half the diameter of the entire planet. If you look near the top of the image, you can see that it’s partly in shadow, and the low angle of the light from the Sun exaggerates vertical elevation changes much as they do here on earth just after dawn and before sunset. So we can see that the upper portion of the surface of Charon Pluto appears to be very irregular and not precisely spherical.

pluto w large crater

Which should be no huge surprise, given how small Charon Pluto really is (only 1200 2300 km across, or about 750 1400 miles, which is much smaller than our own Moon (Luna or Selene), in fact less than the distance from my town (Washington DC) to Miami. In this image the ‘top’ of the planet looks almost like a somewhat-rounded 7-sided heptagon rather than a sphere.

It appears to me that the object (asteroid or comet or whatever) which smacked Charon Pluto and formed that large crater came not along a radius, but at some other angle — I’d have to do some experiments to see whether the object came, so to speak, from somewhere off to our right and from our back as we view the image, or from the exact opposite direction, from above and in front of us, perhaps a bit to our left. I just don’t know if the debris from such an impact would fly back in the direction from which the impactor came, or whether it would continue going forward in the direction of the impactor. It’s fun to do experiments with sandboxes and lofting various projectiles, but you never know how well your set up will match reality. Sand and water at room temperature probably don’t act the same way as the surface of Pluto (various types of frozen ices, at its insanely cold temperatures), being hit by something that vaporizes and melts solid rocks by the tremendous force of impact!

I got the image from here. And thought this was a picture of Pluto. But it’s not.

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