Big data in 1981

Browsing the JPL archives, I came across this image from 1981 for the Voyager 2 mission’s encounter with Saturn. It was designed to illustrate how Voyager 2 would be sending back soooooo much data – look how many books it makes! (Click to enlarge)

Voyager 2 data
Image credit: JPL Photolab, 1981.

I love that in 1981, the artists measured data in terms of books :) Not many people had their own computers or would have understood a discussion of disks or files or bits or bytes, so this was the perfect visualization. Even today, I find it more charming and tangible than most “big data” graphics I’ve encountered.

Cassini has, rightfully, gotten a lot of press lately for its gorgeous images of Saturn, but Voyager 2 was there first and captured its own beauties, like this one:

GPS navigation in airplane mode!

Recently on a trip to Ireland, in an effort to reduce my cellular data consumption, I put my phone into airplane mode while driving across the country. Imagine my surprise when, an hour later, I checked my phone and found that it was still correctly reporting my location, and giving me directions!

I scratched my head about this for a little while. The moving map was updating my position even in airplane mode! It was also scrolling the map as I moved. So it must be the case that

  1. Google Maps downloads and caches enough information that it can continue to show you the relevant map info even if it loses a data connection to its server, and
  2. The GPS receiver in the phone continues to operate in airplane mode.

This had never occurred to me! I was able to confirm it at other times during the trip. If you try to get directions from Google Maps when in airplane mode, it doesn’t work – you can’t search the maps. But if you get the directions started, then go into airplane mode (i.e., turn off cell data), then it will correctly continue to give you directions. However, if you deviate at all, it cannot re-route you, so you have to figure that out for yourself.

I decided to test this during a recent cross-country flight. Right before a flight from Los Angeles to Philadelphia, I got driving directions from Google maps (see right; it wants me to start on Sepulveda Blvd) and then I put the phone into airplane mode.

A few minutes after takeoff from LAX, we were out over the ocean and Google Maps was still urgently telling me to get onto Sepulveda Blvd:

I checked on the directions periodically throughout the 5-hour flight.

Each time we had made some more progress, but we were so far off the (road) track that Google Maps kept saying to go back to Sepulveda Blvd and start over.

As we got close to the Philadelphia airport, we were close enough to match up with a road (briefly) and the directions made more sense.

So cool! This means that even when an airplane doesn’t bother to give you that awesome moving-map track of where the plane currently is, you can still get it, IN AIRPLANE MODE, on your phone! (But only if you got some directions first.)

First transatlantic flight

Recently I got to visit the site of the first transatlantic flight’s landing – in Ireland. The June 1919 flight was achieved by John Alcock and Arthur Brown in a biplane.

These were two interesting aviators! They were both pilots during WWI (although not together), and they were both taken prisoner (Alcock in Turkey, Brown in Germany) and then (presumably) released. Alcock approached an airplane company called Vickers to suggest that he fly their Vickers Vimy IV bomber in the race to see who would be the first to cross the Atlantic. Brown joined up later and due to his exceptional navigational skills was chosen to fly with Alcock.

The 16-hour flight itself sounds pretty harrowing. They departed Newfoundland at 1:45 p.m. They had several equipment problems including the loss of their radio, intercom, and heating. They were flying in a biplane with two open-cockpit seats! Bad weather meant Brown couldn’t use his sextant to help them steer from 5 p.m. until midnight. Happily, they still made it to Clifden, Ireland, and ended up landing next to Marconi’s transatlantic wireless station (an excellent visual landmark). Unfortunately, they thought they spotted a stretch of open ground to land on that turned out to be a bog, so when the plane landed and slowed, it sank nose-in. They escaped unhurt but the plane was damaged. Still, heroes who won the 10,000-pound prize!

From Wikipedia, this appears to be an actual photo taken after landing:

They also carried a small mailbag so they could count their flight as the first transatlantic airmail flight :)

As usual, I am awed by the courage and daring of early aviators!

The Art of Getting There

Today I had the pleasure of visiting the Pasadena Museum of History. I went to check out their exhibit on railroad-inspired art. It was delightful! Among other things, several of the pieces were inspired by the very steam locomotive that I got to operate a few weeks ago (see art at right!), as well as other engines and people from the Nevada Northern Railway.

One artist whose work I enjoyed was Bradford Salamon. The first item in the gallery is a dynamic locomotive he painted (titled “Unknown Adventures”), which sadly I cannot find online or on his website to share with you (and photos were not permitted). It was accompanied by a charming statement describing how he enjoys painting “portraits” of objects, not to reproduce the objects, but instead to trigger a memory or feeling associated with them. He paints typewriters, phones, radios, cars, … and trains. Here is one of his trains that I was able to find:

There were also several woodblock prints from Japan that were commissioned to get the public excited when trains were first introduced in Japan (~1850s). Because they were commissioned before the trains actually arrived, and none of the artists had ever seen one, they often copied from U.S. or British publications that showed steam engines… and in one case a steam fire-engine (to put fires out)!

One artist copied from a picture of a train on the Panama Railway, in which one car had “U.S. Mail” printed on it; in the Japanese version, this became “U.S. Maus” (‘maus’ happens to be ‘mouse’ in German). The gallery showed the source images that the artists had used, and you could definitely see how “Mail” could be misinterpreted as “Maus” if you did not speak English!

Here is the Panama original (but not at high enough resolution to read the relevant letters):

Now I want to ride the Panama Railway! You can – it’s a one-hour ride that costs only $25, and includes an open-air viewing deck! Time for a trip to Panama? :)

How to drive a steam locomotive

I recently got to drive a steam locomotive! The Nevada Northern Railway in Ely, NV, allows you to Be the Engineer for a 14-mile trip up and down hills, through two tunnels, and across several road crossings. This is an incredible experience – visually and physically!

(By the way – I learned that you “run” or “operate” an engine, not “drive” it, since no steering is involved. But that is how they describe the experience to newcomers :) )

Did you ever see such a beautiful engine?


NN 40, built by Baldwin in 1910

Before climbing into the engineer’s seat, I had to study a 122-page rulebook and take a short (open book) exam. I learned about whistle signals, hand signals, speed limits, track warrants, air brakes, and more. I learned radio protocol (interestingly, it’s backwards from typical airplane conventions; you announce who you are and then who you want to speak with, e.g., “NN 93 to NN Conductor 93, over”). In addition, “the use of ten codes” (I assume this means things like “10-4”) is prohibited.

I also helped get the engine ready for action. The rest of the crew gave me small jobs, like greasing the many bolts that connect rods and other pieces, and refilling the oil reservoirs. Meanwhile, they stoked up the fire in the boiler, cleaned the engine, filled up the tender’s 6000-gallon water tank, and ensured we had enough coal. The steam engine goes through 75 gallons of water *per mile* and consumes about a ton of coal in the 14-mile trip we did!

After three hours of prep, the engine was ready to go! I climbed up into the cab and learned how to start and stop the engine, then practiced this while we were still in the railyard.

The primary controls are the throttle and the brake. The throttle is a squeeze lever with many (~20) detents. Bouncing along, it requires some fine eye-hand coordination to move it precisely to the desired notch. It, too, is backwards from the throttle on an airplane: moving it out (towards you) gives you more steam, not less!

The brake is a smaller handle, easier to manipulate. If you want to slow down, you move it to a setting that allows compressed air into the brake cylinders, pressing the brake shoes against the wheels. You monitor how much brake you are applying through a pressure gauge. Then you move the handle the other direction to release the compressed air (you can hear it hiss out) and the wheels resume unimpeded motion.

The massive locomotive responds slowly to control changes, so both controls are best applied with careful anticipation of the upcoming track – its grade, any curves, preparation for tunnels, etc.

There is also a reversing lever that is mounted vertically in the floor. As one of my books warns, “A strong arm is needed for the reversing lever!” It has a more subtle effect on locomotion by altering the amount of steam that gets into the piston cylinders on each stroke. You want it set full forward to get moving, then back it off for “cruise” to achieve more efficient operations.

And we were off! We left the railyard and climbed a gentle hill. We went through two tunnels and several road crossings. For each crossing, I blew the whistle – LONG LONG short LONG! Mike, our fireman, was busy shoveling coal as needed, injecting more water into the boiler, and ringing the bell through all crossings as well. What a delightful noise!

We used a GPS-based speedometer to track our speed, which stopped working each time we went into a tunnel. However, after a while you get a feel for speed based on the sound of the pistons (and such a lovely sound it is). Pistons mounted on each side provide the driving power for the large wheels. Each wheel gets driven twice per rotation (unlike engines in cars, airplanes, etc.):


In addition, the left and right wheels are offset in phase so that one side gets maximal torque when the other is at minimum (end of its stroke). So what you hear is CHUFF-chuff-chuff-chuff as the pistons go right-forward, left-forward, right-back, left-back, for a smooth continuous overall motion.

At the top of the hill, I gave the controls over to John, the engineer who was training me, and he traced our way through a “wye” (track set up to enable a three-point turn by an engine), which got us set up to return back downhill.

We then continued back down the hill to return to the railyard. The whole trip took about an hour and 15 minutes. After the initial learning curve, it got very comfortable to roll along and listen and respond to the chuff of the pistons as needed. My mind quieted and I filled up with the pure joy of the moment. What an overwhelming experience!


Me driving Number 40

Thank you to Richard Ondrovic for taking these fantastic photos!

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