We are getting part of the "family" at Linux World Expo San Francisco edition. Our booth was in the ".org" pavillon. We had a nice success. The ".org" pavillon is an area of about 20-25 small booths nicely reserved by the organizer (IDG) for non profit projects. It was the first year the linuxastronomy booth had more than one person taking care of it. It endedup being a great way to do it. The work load has been spread and the hardship of before the show divided between Ron and Eugene. Richard helped on the logistic while the show was going on, Christian loaned us a digital voltmeter, as one has been fried while testing not long before the show, while Jerry worked on a new driver for our program pyDmm. Matthew did some painting, drilled a few holes in the aluminum used to make the seismometer. Mica printed the beautifull banner, Susan helped with the logistic, especially to sort some confusion in a situation with the company that has the monopoly on the show floor work. Jim joined us all the show days and was also a great help with his astronomy knowledge.

Picture above by Robin Miller.

The exhibitors are having a good time. Both of us stayed at the booth the whole time. Jim is an astronomer, he joined forces with us by bringing his incredible knowldge of the sky. By the end of the show he was almost as familiar with linux as anyone around. His Web sites are a delight for astronomy enthusiasts of all ages, especially for young people. www.educapers.com www.itsmysky.com

While last year we presented a home made telescope. This year we had on display a home made Seismometer. It was a success, we did not anticipate. It generated a lot of questions and interest. I guess we are in the right location for frequent real world testings... Hitting the floor, to increase the vibration level already high, is a good way to bring attention... The seismometer had no problem to pickup vibrations, even when the show was closed it could pickup vibrations, possibly from the street or the "BART", which is San Francsico Subway system (metro, underground). In "real life" a seismometer would be on the ground floor, not on a shelf. In our case, it was on display on a shelf for convenience, it was easier to observe it. Harry from the "Open Source Education Foundation" was or neighbor (on the left). www.osef.org
People jumping on the floor, to see the result of the newly created vibrations, in almost real time on the seismometer program. Small crowed of people jumped together all 3 days of the event.
Seismometer detail. At the top center in dark green is the pickup coil. It concist of 30'000 turns of wire much thinner than a human hair. The coil is made of copper wire used in the manufacturing of guitars microphones pickup coils. Ron made it using a winding machine at Alembic. In the center of the coil, we can see the ceramic magnets. When a shock or vibration happen, the long (horizontal) threaded rod start moving slightly. By the action of the magnets moving in the coil vicinity, an electrical signal is generated and the coil pickup the new signal. Which is send to an analog to digital interface, in our case a voltmeter with a serial port (RS-232c). The two pulleys, are a temporary solution for the show. A counter-weight will be replacing the two pulleys at a later time.

Seismometer assembly. The whole assembly as it was for Linux World Expo. At the show a simpler metter was used instead of the one on the picture. The seismometer will still need a little bit more work to be properly operational, such as a heavier counter-weight and a bigger "Eddy curent" brake. The little rope will be replaced by a metallic wire. What does a seismometer has to do with astronomy ? While it is unusual to have such a tool next to a telescope, it can help by providing some information on locating vibrations. In our case, we are diversified and do many different things. The construction of a seismometer can be a fun and not to complicate project for a teenager. It can also be used to monitor the vibration level at a telescope site, as well as monitor the vibrations generated by a homemade telescope.

Example of seismometer reading using our program pyDmm. This program version used with a Mastech M9803r.
Example of seismometer reading at the show. This program version used with a Metex Me-11, Radio-Shack 22-805, and many others similar meters.

The seismometer is on the left, the display of the showfloor vibrations on the right side of the booth. Our program (pyDmm) is visible on the big monitor. The laptop computer on the lower left is a Compaq LTE 5300 with a P1 133 MHz, several people were amaze by this relatively old laptop. That was a nice show, we are tired, but we had a good time, our memory are full, see you next year.

2004/08/19 Example of seismometer reading, in the "real world". Screenshot taken after the show (August 19th 2004). This program version used with a Metex Me-11, connected to the seismometer. The thin peak going up in the middle of the screen represent some motions, it can be a cricket jumping on the seismometer or a real motion. The thin peak going down toward the right of the screen, represente a power outage of about one seconde. In this case it was the evaporative cooler motor that kicked in. The resolution was 2 seconds, with about 3500 samples displayed on the screen at this time. A resolution of 2 seconds is not enough for quality earthquakes detection, meanwhile it is fine for a proof of concept.

2004/09 Seismometer modification. The seismometer weight used at the show, was too light. A new temporary weight has been added, it concist of 17 bolts 1/2" x 4.5" (about 12.5 mm x 110 mm). The motion are now more realistics, the dampering seems better also.

2004/09/16 A small earthquake happened close to the seismometer location, it has been confirmed on the USGS website (US Geological Survey). This is a great news for us, it is the first time we can make a connection with a real event. The following links are on the USGS server, we do not have any control on them, they may or may not be available by the time you read this page. Archive of the event, it is on the 2004 folder: USGS, Archive of SjakeMaps from 2004. It is the earthquake that has the event ID: 14091288. Intensity map: USGS, Rapid Instrumental Intensity Map Epicenter. California-Nevada Earthquake Map of the latest events, from USGS website (US Geological Survey): USGS, Index map of recent earthquakes in California-Nevada.
The peak on the right of the picture, is a good example of a real Earthquake a few miles away from us. It was in Yucca Valley, Southern California (near Joshua Tree national park). The magnitude was 3.6 on the Richter scale. The event happened on August 16th 2004 at 6:29 pst (Pacific Standard Time). The computer clock was slightly off at the time of the quake.
Detail of the earthquake, discribed above. This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" is not used either in reloading mode. It is a new feature and is not implemented yet in reloading mode.
Same event using the step feature of pyDmm. This view has also been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" is not used either in reloading mode. It is a new feature and is not implemented yet in reloading mode.

2004/10/14 A small earthquake happened close to the seismometer location, it has been confirmed on the USGS website (US Geological Survey). This is a another good news for us, we are happy we can make a connection with one more real event. This small earthquake seems to show that our seismometer is pretty sensitive, at least in the North South axis. The following links are on the USGS server, we do not have any control on them, they may or may not be available by the time you read this page. Archive of the event, it is on the 2004 folder: USGS, Archive of SjakeMaps from 2004. It is the earthquake that has the event ID: 10053685. Intensity map: Pasadena USGS, event history..
The peak on the right of the picture, is a real Earthquake just a few miles away from us. The magnitude was 1.4 on the Richter scale. The event happened on October 14th 2004 at 5:48 (am) pst (Pacific Standard Time). The computer clock was slightly off at the time of the quake.
Detail of the earthquake, discribed above. This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" was 1.5 second, meaning the program took a reading every 1.5 second, which is not enough for an accurate earthquake event, but fine for a proof of concept.
2004/10/14 A few hours later, another small earhtquake, we had quiet a few small one on that day.
Detail of another earthquake a few hours later on the same day. It was a 2.3 on the Richter scale. This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" was 1.5 second, meaning the program took a reading every 1.5 second, which is not enough for an accurate earthquake event, but fine for a proof of concept.
2004/10/15 Another one, that seemed to be pretty local and felt stronger than the quakes of the previous day, at the seismometer location.
Detail of another local earthquake On October 15th 2004. The intensity is not know yet at time of this writing. This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" was 1.5 second, meaning the program took a reading every 1.5 second, which is not enough for an accurate earthquake event, but fine for a proof of concept.
2004/10/18 This earthquake was just a few chocks, no vibrations were felt at the seismometer location, it was brief but stronger than the ones from the previous days. the brusk chocks seem to correspond most of the time at a local event. It has been confirmed by the USGS website, it happened about 12 - 15 miles from us.
The intensity was 3.2 on the Richter scale and was located in Anza California. This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" was 1.5 second, meaning the program took a reading every 1.5 second, which is not enough for an accurate earthquake event, but fine for a proof of concept. Archive of the event, it is on the 2004 folder: USGS, Archive of SjakeMaps from 2004. It is the earthquake that has the event ID: 10054541. Intensity map: Pasadena USGS, event history..

2004/10/30 On October 28, I noticed some behaviors I have not seen, since we began reading the seismometer data. We had several hours of small shakes, not perceptible for most people, but a constant rattle, it lasted several hours. This curious phenomenon stop early in the evening, started again on the 29th for a few hours also but at a different time. On the 30th it started again for a several minutes at the time. This phenomenon seems to happen day or night. At this point in time, the cause is unknown. I discraded a few of them (after evaluating the possibilities) such as: Trucks passing by, pump of a septic tank behing emptied by a truck (we still do not have sewer systems), Earth moving equipment, and some more. I did not discard (yet) some others, such as a mal-function of the seismometer, the digital multimeter having some difficulties, some nuclear or military testing (?). Another possible reason could be the rain. It is a point to consider as they are just a few days of rain each year at the seismometer location, which is in the Southern California desert. The rain came and pourred into the area. I wonder if the building or the concrete floor have some dilatation due to the augmention of humidity. I doubt it is a sign of a big earthquake coming, as I would guess the media would have been crazzy talking about it.
The following images describes better the curious event.
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At that time, the situation was "as usual" again, but the seismometer recorded a small shock.
On this image, the situation looks alarming, in fact it is one of the most peaceful moment. The graph has an autoranging feature, which display the minimum and maximum value as the bottom and top part of the graph. No panic here, everything is under control, it is the most quiet time or "le calme plat" (when a sail boat is stuck on a water surface with no wind at all).
Something seems to have started again.
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This image is not great, as the line is only 1 pixel wide and I reduced all the images, as well as narrowed the number of colors, with for goal to reduce their download time.
On this image, we can notice the end of a micro shaking time (supposing it is that), then on the right side, the beginning of a quiet time.
2004/11/02 Some strange behaviors seem to have started again today. Here it may be a micro earthquake.
I still can not attribute this shake to anything familliar, except as discribed earlier, a malfunction in one of the component, or maybe some earth movement down, under our feet.
This view represent the end of the unknown event.
The "calme plat" one more time.
2004/11/15 The peak on the right of the screen seems to represent the brown "UPS" truck (postal delivery truck) racing as a dragster for about 100 ft (env. 30 m) on a dirt road drive way (made of corrugated sand) (french: chemin en tole ondulee) which is about 60 ft (env. 20 m) from the seismometer location. This is not a certitude as for a few hours on that day, we had a lot of small earthquakes, but it seems a good possibility. The Pasadena USGS site showed a lot of small activity for our area on that day, meanwhile nothing seems to have been recorded on their site at that time of the day.
2004/11/21 The peak on the right of the screen seems to represent a Thunderstorm. We had heavy rain as well as snow pretty low in the night then a few thunderstroms, this is one that probably was not too far.
Detail of the thunderstorm. The thunderstorm is definitely a too fast event for our digital multimeter. The date represent the date and time the data were reloaded into pyDMM, "not" the time it happened. The event happened on 2004/11/21 around 04:30 am in the morning.
2005/01/12 00:11 am Exact time of the event (by USGS, US Geological Survey) Wednesday, January 12, 2005 at 00:10:46 AM (PST) Wednesday, January 12, 2005 at 08:10:46 (UTC) We had a shock nearby us. The intensity was 4.3 on the Richter scale and was located near Desert Hot Springs, Southern California. This event has been confirmed by the USGS. This earthquake was just a few chocks, no rolling effect were felt at the seismometer location, the brusk chocks seem to correspond most of the time at a local event. It has been confirmed by the USGS website, it happened about 12 - 15 miles from us.
This view has been created by reloading part of the data into the program (pyDmm). The time represent the time the data were reloaded NOT the time of the event, as this feature was not yet implemented into the program, at the time the event happened. The "interval" was 1.5 second, meaning the program took a reading every 1.5 second, which is not enough for an accurate earthquake reading, but fine for a proof of concept. The event is currently listed on the USGS website, as a recent event (2005/01/12), its page location might change : USGS website for the event id : ci14118096.
2005/01/12 00:11 am Detail of the event. The time represent the time the data were reloaded NOT the time of the event.