Telescope Designer and Astronomer John Dobson, 1915-2014 57
As noted by Sky & Telescope, SpaceWatchtower, and many other sources, astronomer and telescope innovator John Dobson died yesterday in Burbank, California, at the age of 98. He's famous as an inspiration for others to explore astronomy, in part through the San Francisco Sidewalk Astronomers, which he co-founded in 1967, and as designer of the telescope variety which bears his name.
my dad (Score:5, Interesting)
Godspeed John! (Score:5, Interesting)
~Vincent van Gogh
Still using my homebuilt Dob (Score:5, Interesting)
I built an 8in Dob back in 2004 using the plans from the San Fransisco Sidewalk Astronomers. You can stargaze with others using fancy electronic scopes but the interest always turns to the homemade one. A worthwhile project for anyone who enjoys astronomy.
While my Meade Lightbridge gently weeps... (Score:5, Interesting)
My astronomy group hosted John a few years back for a lecture, sadly I didn't make it but he did stay at a member's house for a few days while on his tour. The guy who hosted John still has an 8 inch dob that is signed by John Dobson. It's always neat when he brings it out to the star parties. Also, a few members have engaged in sidewalk astronomy over the last few years. I think this is another tip of the hat to John Dobson who was still doing his sidewalk work until at least mid 2013.
The Ford of telescopes (Score:5, Interesting)
R.I.P., John (Score:5, Interesting)
It's a sad day. He did so much to advance the art of telescope making and to make the night sky accessible to everyone.
Perhaps a fitting memorial would be a national "dark skies" law, so that we all can have a night sky worth looking up for.
Re:my dad (Score:5, Interesting)
He got ambitious several years ago, and found 5 ft diameter piece of mirror making glass being sold by a college on Ebay for cheap. That is a big effing mirror. Once he had it in his house, the enormity of the task of doing anything with it became obvious. ha!
Massive loss, but not unexpected (Score:4, Interesting)
John was getting into frail health a few years ago. I would have liked to meet him back in the 70s or 80s. Someone in our astronomy club latched onto video of him back then and it's a real hoot to watch. He was definitely a hoopy frood.
RIP
Re:While my Meade Lightbridge gently weeps... (Score:5, Interesting)
a bit more? a lot more affordable. I helped a friend build a 38" diameter Dob for 1/10th the price of anything else available even near that size. Being able to see individual rings of Saturn (and having enough light gathering to almost blind you from looking at Venus.) is huge The thing was so good at light gathering that you could see the horsehead nebula with your naked eye if you did not look at it directly. Most scopes require at least a 30 second exposure to even start to image it.
For large scopes Dob is your only choice unless you are filthy rich. The stereo 8" set we built was also insane.
Re:my dad (Score:5, Interesting)
The most remarkable thing about John was his setting up on Street Corners in a city. Even with all that light pollution he could show people some of the more astounding things in the night sky.
I've set up my 10 inch SNT on street corners a couple times, though a bit uneasily as I always worried someone would knock it over. Showing the moons of Jupiter and Saturn was always a lot of fun. Once at Skies over Yosemite, as I was just setting up and had the scope aimed at Jupiter someone saw a "spot" on Jupiter. I thought it was going to be another damn episode of "mascara on the eyepiece", but turned out to be Io in transit. It was two hours later, when Io's shadow passed from the face of the jovian sphere and I was able to get my polar alignment done.
Dobs are such a treat for families because they set up and are easily managed with a minimal effort, unlike the monster I have. Maybe at some point I'll toss the Equatorial Mount and turn it into a Dobsonian mounted scope. :)
Nice guy (Score:5, Interesting)
My parents live in a small town, and the community college ran a seminar he taught. He and his young son ended up back at my parents house for dinner a few times while he was in town. His son was very happy to eat there, as apparently Mr. Dobson prepared many of his meals in a blender. They called it goop (or something like that).
His kid played with the Legos still in the house from when I was a kid, and there's still a small Lego shrine in my parents' display case that says "John Lowry Dobson".
The speak fondly of the time they spent with him, even though it was 15 to 20 (?) years ago.
Re:Nice guy (Score:5, Interesting)
John stayed with us in the UK back in 2002 - that Wikipedia article picture should have me just out of shot... We took him to see the city of Chester - which John insisted on seeing the city walls "The last city I saw with walls was Beijing in 1920" I think he said. We took him to North Wales to see the sights there, and then he stayed in my home for a couple of memorable nights, when he baby-sat my eldest son while I rushed my baby son to the ER having found him bleeding and screaming after climbing a bookcase and cutting his head open. "John, I really, really need to get this little guy to hospital. Can you tell my wife where we've gone and look after this one ? " "Aw, sure, no problem". I came back to find John reading a book to my son. I have video of John "lassoing" the kids out in the yard with a rope he always carried to demonstrate with !
One of those visits that will stay with me forever- the youngest son is now 13, and still has the scar......
Traveling with John (Score:5, Interesting)
In the late '90s I met Jane Houston, who assisted John in his telescope making classes at the California Academy of Sciences. Her garage was full of mirror blanks, grit sorted into particle sizes, and pine-tar pitch for making pitch laps. I married her in 2000. (Yesterday John passed away on our 14th wedding anniversay.)
Over the next few years, we would often get a call from John at his home in San Francisco, and he would say "It's clear out! Should I finish my dinner?" That was our cue to load the van, pick up John, and take him to either 9th & Geary, or 24th & Noe, and spend the evening doing sidewalk astronomy. We would often have three or four hundred "accidental astronomers" participate in what we call "urban guerrilla astronomy."
During the summers, we took at least three excursions with John to the Grand Canyon Star Party. There's not much in life to compare with spending eight or ten hours on the road with John. He would make the most interesting observations of the landscape around him, or sometimes just launch into a new puzzle for us. You could always count on something interesting from John when he would say, "Okay now I have to tell you a story ..."
His views of cosmology were certainly unorthodox, but they were based on a solid foundation and understanding of the physics, chemistry, and math involved. I didn't always agree with his views, but he never failed to give me a fresh perspective on physics and cosmology. He was a fan of Fred Hoyle and Halton Arp, a champion of the steady-state universe. You would often see him in a sweat-shirt that says "The Big Bang is a Thing of the Past," or a button saying "Nothing Doesn't Exist."
One of my favorite John quotes: "Anything that happens is natural. A battleship is just as natural as a pine tree."
And one last John story: We were on our way to the Bryce Canyon Star Party, and passed one of Utah's famous rock shops. He glanced out the window and said, "Oh look! Pieces of planet!" Yes, we spent an hour or so shopping there.
Re:my dad (Score:4, Interesting)
That all said, If I get another scope someday though, It'll be a cassegrain with an EQ mount/motor.
Re: My stepdad (Score:3, Interesting)
My stepdad, Leon Salanave, was one of the architects of the California Academy of Sciences' Morrison Planetarium.
He was a native San Franciscan and an enthusiastic local amateur astronomer, doing a stint as editor of the Astronomical Society of the Pacific's magazine.
As a result of these affiliations I found myself, in 1973, at the age of perhaps 11, with my family - attending a weekend astronomical seminar, sponsored by the ASP, at the Sonoma Mission Inn - which included putting in a few hours helping Mr Dobson grind a lense for one of his giant sidewalk telescopes, several of which were present (they were built out of cardboard tubing found at the center of rolls of carpet, and glass blanks, which were sourced from military surplus glass portholes).
I recall we were also observing the Sun, with a huge telescope that required a stepladder to reach the eyepiece - one that was painted with a wild giraffe motif, if I recall correctly.
Mr Dobson used a large concave surface, with a bit of abrasive material at the center, and we all took turns moving the blank about, in a rhythmical and circular motion.
I remember asking if I was doing it right - he told me there was no wrong way to do it, because it would all even out, in the end. Which was really comforting. And empowering. Making a lense was something that anyone could do.
I had never been exposed to such a positive and rewarding educator of young minds before. I think it made an impact. He raised the bar.
Thank you, John.
Re:my dad (Score:5, Interesting)
When the Venus transit happened I set up my little orion in the driveway and projected the image onto a sheet of paper and within 10 or 15 minutes a mob of people from my neighborhood (most of whom I'd never met) had gathered around - parents on walks with their kids, dogs, or out jogging, what have you - it was great. They were all talking about it, asking questions about it, generally marveling at the image.
The best part was explaining it to the kids - I would explain what was happening, they would turn to the image again, and a few seconds later you could see on their faces the realization of the scope of what they were witnessing. It was really great. I can see why he did it.
Re:Still using my homebuilt Dob (Score:4, Interesting)
I think laypeople underestimate Dobsonians due to their "homebrew" nature. Dobs are wonderful for visual observation. What matters most is light gathering, which is purely a function of primary mirror/lens size. Expensive equatorial tracking mounts, Cassegrain optics and other expensive things are nice, and needed for astrophotography or special uses; but for simply viewing, the sheer size of a Dobsonian means you can get far more viewing power for a fraction of the price.
Wow... (Score:4, Interesting)
I guess what surprises me, is how many people know Dobson.. or know of him.. I'd met him a few times over the years, and attended a couple of his classes at the Vedanta center in Hollywood. The man was always so nice, and some of his ideas about the cosmos are very much non-western in thought, and always fascinated me.
Its nice to see slashdot mention him.
Seeing what everyone else has seen... (Score:4, Interesting)
...and thinking what no one else has thought.
John visited our science center years back, asked us for an old 8" floppy to tear apart and improve the mount action on our big DIY Dob. Signed it too. We also brought him to our mountaintop sundial that at 18' across is the "sun" for a 2" earth-scale solar system that goes out ~14 miles. We were pointing out the landmarks for the planets, and he started pacing. Dang. We figured we bored him with our little project. We asked him what was wrong. He said "Nothing - but watch this," He walked the diameter of the "sun" while counting "1..2..3..4.. See?! I can cross your sun's diameter in the same four seconds it takes light to travel the 865,000 mile diameter of the real sun - so on your model, walking is the scaled speed of light!" In ten years, a dozen of us had never thought of that. Bonus is when we have students do the annual bicycle "Tour de Solar System" on the local rail trails, we can tell them they're pedaling at warp 3 or whatnot...
Legend (Score:4, Interesting)
Another, probably apocryphal, story was John claimed to have star tested a scope using the glint of light off the eye of a blackbird, perched on a telephone wire down the street - really, really good telescope makers can identify the condition and quality of a mirror by studying the shape of the image from the scope just inside, and just outside focus.
Re:Seeing what everyone else has seen... (Score:4, Interesting)
Sounds like a fun place to visit. Where is this?