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Telescope Designer and Astronomer John Dobson, 1915-2014

timothy posted about 3 months ago | from the now-he-gets-the-whole-sky dept.

Space 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.

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57 comments

my dad (5, Interesting)

buswolley (591500) | about 3 months ago | (#45977391)

built a Dobson telescope when I was a kid. Many memorable nights in the back yard with that Dobson.. RIP

Re:my dad (1)

sideslash (1865434) | about 3 months ago | (#45977475)

Same here. Ours had a 13 inch mirror at the bottom.

Re:my dad (4, Interesting)

buswolley (591500) | about 3 months ago | (#45977741)

About the same here. I also always remember that he converted a washer machine into a mirror grinder to get the mirror into the rough dimensions. Then the endless days of fine grinding and testing. I recently asked him about the washer machine approach and he grinned and said, "that was wild, but I'd do it differently next time."

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!

Re:my dad (0)

Anonymous Coward | about 3 months ago | (#45977943)

I'll bet that with a couple hundred bucks he could put together a fairly good CNC rough grinder with linuxcnc. Cut out a month or so of nasty manual grinding.

Re:my dad (4, Interesting)

ackthpt (218170) | about 3 months ago | (#45978143)

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. :)

Re:my dad (1)

Anne_Nonymous (313852) | about 3 months ago | (#45978357)

>> Even with all that light pollution he could show people some of the more astounding things in the night sky.

In Burbank, California you can even see the stars in the daytime.

Re:my dad (5, Interesting)

jomama717 (779243) | about 3 months ago | (#45979915)

That's great. It's amazing the level of interest that people express when they are presented the opportunity to view these things with no effort or cost associated.

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: My stepdad (3, Interesting)

Anonymous Coward | about 3 months ago | (#45979891)

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 (3, Interesting)

cyberchondriac (456626) | about 3 months ago | (#45979249)

I didn't build mine but I bought an XT8 from Orion (non -computerized/motorized). Dollar for dollar, a dob just can't be beat. I saw just about every major Messier object light pollution in my area would allow.. and then some more with broadband filters. As a newbie, I was a little disappointed how monochrome everything was, but without long exposure, that's how it goes.. Better than not seeing these things at all. I got a real good peek at Mars though in opposition in 2003. It's been a long time though. The LP is so horrendous near Philly that I kinda gave up. I'd have to pack the thing up and take a drive down to the pine barrens.
That all said, If I get another scope someday though, It'll be a cassegrain with an EQ mount/motor.

Damn (0)

Anonymous Coward | about 3 months ago | (#45977395)

I'm sorry to read this.

Re:Damn (1)

sideslash (1865434) | about 3 months ago | (#45977499)

Well regarded for his accomplishments: check.
Long life: um, extra-check!

So why are you sorry to read it?

Re:Damn (1)

Anonymous Coward | about 3 months ago | (#45977659)

Long life: um, extra-check!

Not that long. 90 is the new 70.

Godspeed John! (4, Interesting)

Bodhammer (559311) | about 3 months ago | (#45977397)

“For my part I know nothing with any certainty, but the sight of the stars makes me dream.”
~Vincent van Gogh

Re:Godspeed John! (0)

Anonymous Coward | about 3 months ago | (#45977941)

“For my part I know nothing with any certainty, but the sight of the stars makes me dream.”

  ~Vincent van Gogh

...and how much do our modern light polluted skies obscure them. :-(

Thank you Mr. Dobson, and RIP - from another amateur astronomer and a proud maker of an 8 inch "Dobsonian".

Still using my homebuilt Dob (5, Interesting)

hodet (620484) | about 3 months ago | (#45977469)

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.

Re:Still using my homebuilt Dob (3, Interesting)

nitehawk214 (222219) | about 3 months ago | (#45980315)

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.

While my Meade Lightbridge gently weeps... (5, Interesting)

east coast (590680) | about 3 months ago | (#45977505)

It's good to see the recognition for a guy who helped make it a bit more affordable for backyard stargazers to get into a serious scope without selling a kidney.

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.

Re:While my Meade Lightbridge gently weeps... (4, Interesting)

Lumpy (12016) | about 3 months ago | (#45977983)

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:While my Meade Lightbridge gently weeps... (4, Insightful)

Anonymous Coward | about 3 months ago | (#45978987)

And what's interesting is that the design then morphed into the high-end, large commercial dobs that you can buy today. They aren't cheap, but the performance is great and they are very portable. Combining the dobsonian mount with a truss-tube allows me to load my 15" Obsession into the back seat of my car. I've seen a 20" go into a small hatchback. Dealing with the poles was a little tricky, but the bulk of the equipment went right in.

And don't think of this as being "low-tech". The design is simple and the materials cheap but the combination of a large bearing surface, formica and teflon, and perfect balance in the scope results in amazing performance. Move the scope and it just slides around the sky. Take your hand off and it stops right where you want it. I love doing that rather than fiddling around with motors and gears and buttons on a hand controller.

I know the expensive commercial dobs weren't quite what he had in mind, but the mount innovation changed amateur astronomy, for the way better. Thank you Mr. Dobson.

The Ford of telescopes (5, Interesting)

SpankiMonki (3493987) | about 3 months ago | (#45977507)

We need more guys like Dobson. RIP.

Re:The Ford of telescopes (2)

ackthpt (218170) | about 3 months ago | (#45978013)

We need more guys like Dobson. RIP.

Alas, I was one of those people who threw money into higher end scopes than was probably prudent for a beginner. Though I really do like my 10 inch SNT, I would have likely been happier with a "Dob". "Dobs" are what I recommend to all budding astronomers - don't waste your money on one of those crummy refractors they sell in the malls. Take $400 and buy yourself a decent 6 or 8 inch "Dob" from Meade or Orion and you will have a blast. You'll also be able to see deep space objects your 2 inch refractor isn't going to.

Back seat of your Ford (2)

Latent Heat (558884) | about 3 months ago | (#45978339)

I second that recommendation, and get the biggest "Dob" that will fit in the back seat of your car.

If you can't transport it, it won't get used.

Re:The Ford of telescopes (-1)

Anonymous Coward | about 3 months ago | (#45978421)

Geez, you're such a karma whore.

Re:The Ford of telescopes (-1)

Anonymous Coward | about 3 months ago | (#45979487)

Geez, you're such a karma whore.

Instead of posting insightful/informative/funny comments that might get modded up, everyone here should just post snarky bullshit as AC like we just did.

Mod us up, bitches!

Re:The Ford of telescopes (1)

ImOuttaHere (2996813) | about 3 months ago | (#45978687)

We need more guys like Dobson. RIP.

Yes. We, indeed do. Thoroughly decent human beings? Their population just decreased by one. :-(

Gave true meaning to expanding the mind (5, Insightful)

voxelman (236068) | about 3 months ago | (#45977547)

John's simple but effective methods for building large aperture telescopes opened the sky to a whole new audience.

Re:Gave true meaning to expanding the mind (2)

ackthpt (218170) | about 3 months ago | (#45978055)

John's simple but effective methods for building large aperture telescopes opened the sky to a whole new audience.

And led to a whole new trend - Aperture Fever - gotta have more light! 8^)

It's highly fitting there is a line of dobs are called Obsession [obsessiontelescopes.com] .

R.I.P., John (5, Interesting)

nani popoki (594111) | about 3 months ago | (#45977685)

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:R.I.P., John (0)

Anonymous Coward | about 3 months ago | (#45978033)

HEAR HEAR!
I'd go for that in a heartbeat.

good riddence to bad rubbish (-1, Troll)

magic maverick (2615475) | about 3 months ago | (#45977913)

If God had wanted us to see far away things he would have given us telescopic eyes. This sinner is now burning in hell for allowing anyone to see the far away places that God had made off-limits.</troll>

Re:good riddence to bad rubbish (0)

Anonymous Coward | about 3 months ago | (#45979243)

He/She did better.
we were given the imagination to design and build the tools we needed.

The best telescope ever designed. (5, Informative)

Lumpy (12016) | about 3 months ago | (#45977931)

Because they were cheap for the size. you can get an 8 inch or larger scope that will let you split the rings of Saturn for 1/2 the price of a lesser scope that still only shows you blobs.

And they are insanely easy to maintain.

RIP for the man who made decent astronomy available to the poor man.

Re:The best telescope ever designed. (2)

dargaud (518470) | about 3 months ago | (#45979279)

I read that 3 times as: "1/2 the price of a lesser scope that still only shows you boobs". And I kept wondering what was wrong with that.

Massive loss, but not unexpected (3, Interesting)

ackthpt (218170) | about 3 months ago | (#45977965)

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

A life put to good use (0)

Anonymous Coward | about 3 months ago | (#45977967)

And a long one it was too.

Nice guy (4, Interesting)

Skynyrd (25155) | about 3 months ago | (#45978185)

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 (4, Interesting)

SteveAstro (209000) | about 3 months ago | (#45978409)

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 (5, Interesting)

MojoSF (658720) | about 3 months ago | (#45978657)

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.

Brief Encounter (2)

alanw (1822) | about 3 months ago | (#45979235)

I once spent an interesting weekend in his company. He'd been born in Beijing, a walled city, and we took him via Chester on our way to North Wales. It was the first time he'd been in a walled city since his childhood. Walking near Llanberis, he found a Yew tree and enjoyed eating the berries. Still my photo of him on the Wikipedia page. Amazing guy, I hope his enthusiasm and inspiration lives on as his legacy.

Opened astronomy to the masses (2)

Lucas123 (935744) | about 3 months ago | (#45979465)

I bought my first Dobsonian telescope when I was a kid. Last year, my wife bought me a beautiful 6-in reflector. I'll never forget the first time I saw Saturn's rings. There's nothing like seeing them "for real" right there in the sky above you. Thank you, John Dobson for opening up the sky!

Nitpick (0)

Anonymous Coward | about 3 months ago | (#45979541)

He actually made a variety of telescope? I have heard of Dobsonian *mounts*, as opposed to telescopes. And yes, utterly commonplace to refer to a Dobsonian mounted reflector as a "Dob" and imply both the scope and mount. (Plus the mounting point must be attached to the tube, somehow, if not built onto the tube.) So I'm wondering if there's something other than the Dob mount that's being referred to here.

One thing most astronomers try to be is accurate. (Sayeth a fan of space for 40 years who just got his first telescope at Christmas.)

Wow... (4, Interesting)

kellin (28417) | about 3 months ago | (#45980791)

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.

Re:Wow... (2)

hey! (33014) | about 3 months ago | (#45980979)

Well, how many people have heard of John Chapman? Almost everybody, but they know him as Johnny Appleseed [wikipedia.org] .

Give Mr. Dobson's legend another 168 years or so to grow. People will still be using Dobsonian telescopes in 2182 AD I am sure, and for as long as there are people with the desires to look into the night sky and to build things themselves last.

RIP (1)

CharlieG (34950) | about 3 months ago | (#45982205)

I have my 8" F6 over in the closet. Man, that simple mount, and the hole idea of "Make a telescope, what's the worst outcome? You're back where you started". Been planning on rebuilding the scope as a truss tube unit. Maybe in memory of John I'll do this over the next few weeks

Very sad. (1)

trevize42 (1086179) | about 3 months ago | (#45982267)

While I no longer have a Dobsonian telescope.... to this day every Halloween for Trick or Treat instead of candy I setup my 14inch Celestron on the sidewalk in front of my house and "Treat" the kids and many parents to views of the night sky. Rest well John Dobson. Rest well.

Seeing what everyone else has seen... (3, Interesting)

jpellino (202698) | about 3 months ago | (#45982553)

...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 (3, Interesting)

SteveAstro (209000) | about 3 months ago | (#45983757)

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:Legend (1)

Iskender (1040286) | about 3 months ago | (#45998067)

That story sounds totally believable to me. I used Ganymede as a focusing aid yesterday (mirrorless camera, overwhelmed by Jupiter's brightness). If I can use a planet-sized moon as a focusing aid, I have no problem believing that a guy like that used a bird's eye for telescope testing. : )

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