Thursday, June 22, 2017

Separating Color Layers in a Digital Image

I'm learning to use Matlab to do image analysis this summer at Northwest Nazarene University (Nampa, ID). The task before me is to learn how to use images taken from drones to count the number of blooms or fruits on a tree. All digital images are three dimensional arrays. The first two dimensions are easy to understand, they're the height and width of the image. The third dimension is color and there are three layers there. So a digital image might be a 2,000 by 3,000 by 3 array. And arrays are an easy mathematical structure to analyze in Matlab.

To mathematically manipulate an image using Matlab, one must first load the image and then split it into three color layers. In Matlab, this is done with the following script.

image = imread('IMGT1818.bmp');  %load the image
imshow(image)                                  %show  the color image
imageRed = image(:,:,1);                  %separate out the first layer, red
imageGreen = image(:,:,2);               %separate out the second layer, green
imageBlue = image(:,:,3);                 %separate out the third layer, blue
figure,imshow(imageRed)                %show the red layer
figure,imshow(imageGreen)             %show the green layer
figure,imshow(imageBlue)               %show the blue layer

A couple of notes here.

First, Matlab is case sensitive. There's a huge difference between the variable f and F.

Second, digital images loaded into Matlab must be enclosed with hyphens because the name of a file is not a variable

Third, the semicolon (;) suppresses output. Without it, the Command Window in Matlab fills with the decimal values of each pixel as an array is loaded or mathematically manipulated.

And fourth, the percent sign (%) signifies a comment. Any text after it is ignored in the script.

So what is the final result of this script? Below is a screen shot of Matlab after splitting a thermal image taken during descent at GPSL 2017.

From left to right, color image, red layer, green layer, and blue layer
Now that the layers have been split apart, further analysis can be done, like making a histogram of each color or finding edges in the image. My goal is to segment images or break them into two portions, those of the things I want to see and then the background. So there's a lot to learn and accomplish yet. I'll post more about my summer research as I learn more.

Meanwhile, readers can try to do this separation of color layers themselves, and without using Matlab (a very expensive matrix mathematics program). The Freeware program, Octave should be nearly identical to Matlab. So you might want to install this program and try out the script I give above.

Many successful image splittings  

Tuesday, June 20, 2017

Recovery Image from Near Space

Whoa! Near Spacecraft on its way down!
Jim Emmert of the Pella in Near Space (PENS) just sent me this image taken by his camera during the ascent of NearSys-17G. This is an image taken at an altitude of 95,000 feet. Within seconds of balloon burst, the parachute is open. APRS Data indicates the near spacecraft is descending at a speed greater than 6,000 feet per minute or around 70 mph. Above the black and yellow parachutes can be seen the scrap of balloon that survived the burst. The payloads at the end of the balloon line are swinging wildly during the early descent when chaos reigns supreme. Jim's camera just happen to take a picture as its module whipped around    

Thermal Infrared

I flew three balloons at GPSL 2017. One of them carried a thermal imager along with other cameras. The signal wire for the cameras accidentally slipped off it's port before launch (so this cable will be taped on next time). This leaves me using Google Maps for identify ground features in the thermal images. The first match I found is over Gypsum Creek. Here's the matching images.

The creek and the trees lining the creek are cooler than the neighboring farm fields. The yellow fields to the north have been plowed, so they get warmer than the crops in the other farm fields.  

Tuesday, June 13, 2017

Racing Drones

I received a grant for racing drones from PCS Edventures. The drone is the RubiQ and we're learning to assemble them now. Cool stuff!

Now that it's assembled, we're getting ready to test the electronics.

Wednesday, June 7, 2017

Prepping for NearSys-17E

The flight train for my next launch is ready to go. Just watching the weather and the flight predictions. Surface winds promise to be a bit higher than I like.

The trackers are KD4STH-9 and KD4STH-12. Total weight is six pounds on a 1200 gram balloon. With three pounds of positive lift, the balloon should make close to 100,000 feet in 100 minutes.

NearSys-17E sans the client payload

Thursday, June 1, 2017

Carbon Capture Plant in Switzerland

Salon has an interesting article on a carbon capture plant just starting up in Switzerland. The plant captures CO2 from the atmosphere for industrial purposes. Purposes like fertilizer for greenhouses is listed as one example.

In time, the Climeworks plant would like to extract upwards of 1% of the CO2 in the atmosphere. The reason being that if we can't get our carbon hunger under control, then let's try removing the gas from the atmosphere before it can do more harm. Cool idea and one that I hope will work.

Can the atmospheric processors from the Aliens movie (1986) be far behind?  

The Salon Article:

The Aliens Movie:

Wednesday, May 31, 2017

May Weather for NearSys Station

The temperature for May increased slightly with a few days uncharacteristically exceeding 90 *F. There are two gaps in the data because of travel days.

There was no snow in May and the month only saw 0.26 inches of rain.

Monday, May 29, 2017

Article 177

NearSys just published article 177. The article is about the recording weather station created for BalloonSats. By flying this device on a weather balloon, one will know the temperature, pressure, relative humidity, wind speed, and wind direction at various altitudes during a near space mission.

Right now, NearSys is experimenting with using such an outfitted BalloonSat to record these conditions every five seconds during the eclipse mission this August.

Verhage, L. (2017). A recording weather station for near space and beyond, Nuts and Volts, 38(6), 54-57. 

Friday, May 26, 2017

CX-10C Indoor Camera Quadcopter.

Preparing to teach a drone class next year means I'm on the lookout for quadcopter ideas. I came across the CX-10C 4-channel drone two weeks ago and I was amazed to what it was capable of doing. This tiny drone is perfect for indoor flying since it costs less than $30, measures only three inches across, and weighs 14 grams.

More importantly, it can record video and take pictures. The 0.3 MP camera's pictures are not GoPro quality, but are nevertheless pretty nice.

I don't get to see the hallway of my school from this altitude.
The video is even better.


The quadcopter is solidly enough built to survive several crashes without a scratch.

Not a bad toy for $30. Here's looking at you, kid.
So I'm thinking about writing a grant to purchase enough of these quadcopters for my class and then handing them out to students when they've passed their first test.

Saturday, May 20, 2017

UAVSonde Data for NearSys Station, 20 May 2017

UAVSonde data were collected at 9:00 PM. Here are the data.

Altitude: 2,224 feet
Temperature: 68 *F
Relative Humidity: 49%
Pressure: 932.5 mb

Altitude: 2,739 feet
Temperature: 64 *F
Relative Humidity: 36%
Pressure: 916.9 mb

Monday, May 15, 2017


There are too many countries in the world that don't have access to basic science tools for things like medical diagnostics. Foldscopes is trying to change that. You can support the development and distribution of these vital tools.

Please check out Foldscopes when you get a chance.

Snow on May 13, 2017

Whoa, late snow! I ran into a mild snowstorm east of Rome, OR. The snow was melting on the road, but sticking to the grasses off the road.

May 13th is the latest day I have seen it snow. October 15, 1987 is the earliest.

UAVSonde Data for NearSys Station, 13 May 2017

UAVSonde data were collected at 6:30 AM. Here are the data.

Altitude: 2,260 feet
Temperature: 36 *F
Relative Humidity: 85%
Pressure: 940.0 mb

Altitude: 2,539 feet
Temperature: 40 *F
Relative Humidity: 85%
Pressure: 917.6 mb

There appears there was a slight temperature inversion. However, the UAV flashed a low battery condition requiring it be landed early. The temperature could be different if the UAV remained aloft for the full 60 seconds.

I still need to gain the gain on the pressure sensor and recalibrate. That need a to be followed by a test of temperature affects on the pressure sensor output.

Sunday, May 7, 2017

UAVSonde Data for NearSys Station, 7 May 02017

UAVSonde data were collected at 8:30 PM (it's been too windy this weekend to collect earlier). Here are the data.

Altitude: 2,247 feet
Temperature: 64*F
Relative Humidity: 17%
Pressure: 931.8 mb

Altitude: 2,739 feet
Temperature: 61*F
Relative Humidity: 15%
Pressure: 916.9 mb

The GPS glitched during ascent. It's probale that the maximum altitude is in error.

Monday, May 1, 2017

Helium Shortage is no Laughing Matter

Chemistry World has an article on the shortage of helium the world is experiencing. In 2006 and 2013, industry was unable to meet the global demand for helium. Industry has responded by recycling helium and being more efficient with its use. Currently, oil drilling is the major source of helium. However, some of the helium fields are reaching depletion and in the long term, the world will need additional sources of helium.

Read more in Helium in Crisis at Chemistry World,

Field Trip at the Treasure Valley Math and Science Center

My chemistry students went on a field trip last week for a water quality activity. I used the opportunity to get some pictures of them working from my quadcopter's perspective.

Students at work collecting water samples and testing them for phosphates, dissolved oxygen, and sediment.
A thermal image of students working in the light drizzle we were experiencing during the field trip.

The Boise Greenbelt is experiencing flooding this spring.

Sunday, April 30, 2017

April Weather for NearSys Station

The temperature for April increased only slightly as the chart below shows. There were a few mornings of frost, which doesn't show in the minimum temperatures.

April wasn't a very wet month. But surprisingly, NearSys Station did get a small quantity of snow. However, it melted quite rapidly.

UAVSonde Data for NearSys Station, 30 April 2017

UAVSonde data were collected at 9:00 AM. Here are the data.

Altitude: 2,293 feet
Temperature: 61 *F
Relative Humidity: N/A
Pressure: 925.1 mb

Altitude: 2,673 feet
Temperature: 57 *F
Relative Humidity: N/A
Pressure: 917.6 mb

I really need to find some time to build a new weather station!

Tuesday, April 25, 2017

Venus: The Morning Star

I got a picture of the Morning Star this morning. Venus recently passed close to the sun and has now reemerged as a morning planet. Look for it as you drive to work in the low east.

Morning Star above the hills and a cloud bank

Sunday, April 23, 2017

UAVSonde Data for NearSys Station, 23 April 2017

UAVSonde where collected at 6:00 PM. Here are the data.

Altitude: 2,276 feet
Temperature: 68 *F
Relative Humidity: N/A
Pressure: 917.6 mb

Altitude: 2,555 feet
Temperature: 64 *F
Relative Humidity: N/A
Pressure: 913.1 mb

Saturday, April 22, 2017

Idaho State Convention

I gave a one hour presentation at the Idaho State Convention today. The talk was on near space and focused on amateur radio operators. It's because of amatuer radio and APRS that modern near space exploration is open to amatuer scientists.

Presenting to hams is one way to promote both the hobby of near space and amatuer radio. Both hobbies endeavour to get young students better prepared for STEM careers.

You can read more about the Idaho State Convention at,

Saturday, April 15, 2017

UAVSonde for NearSys Station, 15 April 2017

UAVSonde data we're collected at 8:00 AM. Here are the data.

Altitude: 2,247 feet
Temperature: 40*F
Relative Humidity: 70%
Pressure: 934.7 mb

Altitude: 2598 feet
Temperature: 36*F
Relative Humidity: 100%
Pressure: 917.6 mb

Friday, April 14, 2017

Snow in Boise on April 14th!

Whoa, wait a minute! The snow is really flying in Boise this morning. Here's the scene out my classroom window.
The snow is starting to stick.

Thursday, April 13, 2017

Another Meadow Lark at NearSys Station

I was able to acquire a slightly better image our our neighborhood Meadow Larks. This time because I was indoors where the Meadow Lark didn't find me a threat. I'm still hoping to get a good picture of one face on so it's yellow and black breast can be seen.
A little closer this time

Found Paper Airplane

Well, one of the student-made paper airplanes was found. Two sets of paper airplanes were launched from my school back on February 24th. The location the airplane was found was just north of Lucky Peak reservoir. That's a distance of close to 20 miles. So I suspect the paper airplane was released at balloon burst, rather than earlier when I thought the balloon trigger would open the bag carrying the airplanes.

A map image of the paper airplane's location.

Sunday, April 9, 2017

Meadow Lark at NearSys Station

I can hear Western Meadow Larks most of the spring at NearSys Station. The problem is trying to get close to them. Today I managed to get a picture by setting my camera to it's six power zoom and walking slowly.

Not as good of a picture as I wanted, but that's the way it is with singing Meadow Larks.

UAVSonde for NearSys Station, 9 April 2017

UAVSonde data were collected at 9:00 AM. Here are the data.

Altitude: 2,263 feet
Temperature: 43*F
Relative Humidity: 44%
Pressure: 940.7 mb

Altitude: 2,621 feet
Temperature: 40*F
Relative Humidity: 52%
Pressure: 917.6 mb

These were collected using the old recording weather station. The new one is not completed yet. When completed, the pressure sensor will be calibrated and the unit flown in place of the current one.

Sunday, April 2, 2017

Results of Bubble Wrap Experiment

On mission NearSys 17C, NearSys performed it's second bubble wrap experiment.

Bubble wrap was one of the experiments on the first flight of NearSys in 1996. In that experiment, it was determined that bubble wrap could survive a Near space flight and provide cushioning. Bill Brown (WB8ELK) also reports he can use it for protection, including thermal protection.

In an effort to update the near space book written by NearSys, it was decided to repeat this experiment and collect some statistics. This included testing other forms of bubble wrap that did not exist in 1996.

The BalloonSat for this experiment carried five patches of bubble wrap. They were, clear with 1/2" diameter bubbles, pink with 1/2" bubbles, clear with 1" bubbles, pink with 1" bubbles, and air pillows. The number of intact bubbles was recorded before flight and then compared to intact bubbles after recovery.

Clear with 1/2" bubbles: 30.6% popped
Pink with 1/2" bubbles: 6.6% popped
Clear with 1"bubbles: 86.4% popped
Pink with 1" bubbles: 14.3% popped
Air Pillows: 100% popped.

One and 1/2 inch diameter bubble wrap patches after their near space flight. The popped 1/2" bubbles are marked in black. All of the 1" bubbles are popped.

It appears that in many cases, air is leaking from one bubble to another. So it seems that desalination of the bubble wrap is an issue. In addition, air may have leaks from bubbles without popping the bubble. One needs to do a better job accounting for the shape the bubble wrap is in prior to starting the experiment. This will prevent a low-fill bubble being treated as a popped bubble.

It's not surprising the Air Pillows failed. They were very full of air prior to launch. The fact that they burst shows that the plastic film used to create the pillows isn't very strong.

The experiment should be re-performed with newer bubble wrap that has not been previously used as packing material. NearSys will next assess the ability of a layer of bubble wrap to keep its interior warmer than ambient air temperature,

Near Space Flight for Open Window School

NearSys arrived in Ellensburg, WA on March 30th to launch two near spacecraft for Open Window School in Bellevue, WA. The launch took place from the Rotary Park in Ellensburg on Friday morning (8:00 AM on the 31st). Both missions were flown in helium since students were involved.

The backup trackers on each near spacecraft didn't produce position reports that the APRS system could understand, so this is under investigation. Otherwise, a sufficient number of position reports from the primary trackers  were recieved, although far fewer from KD4STH-7 than KD4STH-9.

Flight NearSys 17C reached an altitude of 80,041 feet. It's last position report to enter the APRS system was around 5,000 feet AGL. Since the flight landed so far away in the mountains, it took a while to drive to the landing zone and locate the capsules. Rachel was monitoring APRS when KD4STH-7 transmitted a packet. The near spacecraft was then easily spotted 1,000 feet off the road.

Andrew Mechling of Open Window School after recovery of half his students' BalloonSats.

Flight NearSys 17D reached an altitude of 84,668 feet and landed much closer to the launch site. It too landed in the mountains, but the roads in the landing zone are accessed by BIA roads. Google Maps was found to be inaccurate and the roads were not marked with signs. As a consequence, it took four tries to locate a road that actually took us to the landing site. When NearSys arrived, amatuer radio operator Tony Ross (K7EFS) and David Hamann were found at the near spacecraft. The recovery took so long only because of the nature of the roads in this part of Washington.

Overall, a good flight, but one that makes us aware we need better backup launch sites in Washington. Perferrably, one for east-west flights and one for north-south flights.

March Weather for NearSys Station

March continues the warming trend and is not as dry as February.

UAVSonde for NearSys Station, 1 April 2017

UAVSonde data were collected at 8:00 PM. Here are the data.

Altitude: 2,263 feet
Temperature: 68 *F
Relative Humidity: 20%
Pressure: 934.0 mb

Altitude: 2739 feet
Temperature: 61 *F
Relative Humidity: 13%
Pressure: 917.6 mb

I haven't finished building my new UAVSonde weather station yet.

Wednesday, March 29, 2017

NearSys published in an Art/Cultural Magazine

NearSys was just published in Forum 2017, a medium for open discussion. The publisher is the Canyon County Parks, Cultural, Natural Resources office. See,

I have three near space and two astronomy pictures published in the magazine. I guess this my second arts magazine to be published in.

Saturday, March 25, 2017

UAVSonde Data for NearSys Station, 25 March 2017

UAVSonde data were collected at 9:00 AM. Here are the data.

Altitude: 2,240 feet
Temperature: 57 *F
Relative Humidity: 27%
Pressure: 937.7 mb

Altitude: 2,660 feet
Temperature: 47 *F
Relative Humidity: 41%
Pressure: 917.6 mb

Tuesday, March 21, 2017

Printed Circuit Board Presentation at the Cosmos Club

A slide showing what a schematic and what the resulting printed circuit board looks like.
The Cosmos Club is a science and reason club meeting in Boise, Idaho. On the 20th, I gave a presentation about printed circuit boards, or PCBs. The presentation acquainted members in attendance with the nature, function, and design of PCBs. Did you know that PCBs is a $6 billion business?

My take home points were the following.
1. PCBs are today's technology (electrical circuits were built a lot of different ways over time.
2. PCBs are fun and easy to make using software like FreePCB (
3. PCBs are a great amateur science and engineering activity.

I believe that if we incorporate PCB design and manufacturing with microcontroller programming, schools will have a strong combined science and engineering class. A class such as this is one one way to meet the needs of a 21st century America and employment.


Sunday, March 19, 2017

UAVSonde for NearSys Station, 19 March 2017

UAVSonde data were collected at 6:00 PM. Here are the data.

Altitude: 2,270 feet
Temperature: 61 *F
Relative Humidity: no results
Pressure: 918.4 mb

Altitude: 2,542 feet
Temperature: 57 *F
Relative Humidity: no results
Pressure: 917.6 mb

Boise Code Camp

I was invited to present at Boise Code Camp 2017. My presentation was given yesterday afternoon and was on the topic of making dataloggers with PICAXE microcontrollers. I argued that combining collecting science data using student-made datalogger is something that should be occurring in all science classrooms.

The Next Generation Science Standards,, are a proposal to revamp and re-energize school science standards so can meet the needs for a 21st century America. These new standards recognize that science has progressed when the technology for doing science has changed. 

Two prime examples I can think of is the invention of the practical vacuum pump in the mid 17th century and the invention of the practical particle accelerator in the mid 20th century. 

Having students design printed circuit boards for the PICAXE microcontroller and then learning to program it to collect data opens up new science experiences for all students. 

In addition to learning to build and use dataloggers for the sake of combining science and engineering, students are learning to use a tool of industry and a future career.

As a result of developing and giving this the presentation, I will develop a short course in the topic with the goal of teaching for a community education class of summer school. 

An example of the data I shared at Boise Code Camp.

The Photometer datalogger I displayed at Boise Code Camp.

Sunday, March 12, 2017

Washington Industrial Technology Education Association

Friday the 10th found me in Wenatchee, Washington speaking to teachers about using near space to teach STEM.

The main message if my presentation was that the most interesting place on Earth is accessible from anyplace in Earth.

It's always a wonderful experience to share my passion of near space with like-minded teachers.

Teachers agreed with my comment that students learn best when they encounter a discrepant event while immersed in project-based learning.

BalloonSats are a major project-based learning activity. And most students understand that mountains are colder than the land around them because of elevation. But when a BalloonSat equiped with an external temperature sensor detects that the air warms up above 50,000 feet, most students will be surprised and puzzled.

Students can be taught that the Stratosphere gets warmer due to ozone. Most will even remember that for a test. But when discover that for themselves, they'll learn it more strongly and for longer.

So let's make near space available for more students.

Easy Star Gazing for Spring

What a busy week! I gave a presentation on the March skies at the Deer Flat National Wildlife Refuge (see, and two presentations on the spring skies for New Knowlege Adventures Treasure Valley (see, and the Boise Library!, Hillcrest (see,!-at-hillcrest/).

Presenting the Spring Skies at the Deer Flat National Wildlife Refuge. Now you know the names of the lunar phases. Image by Robert Allen/Pro-Image Photography ( 
Presenting the skies of spring to New Knowledge Adventures.Photography by Micki Kawasaki.

UAVSonde for NearSys Station, 12 March 2017

No UAVSonde data were collected last week, it was too windy to launch the UAV. 

UAVSonde data were collected at 4:30 PM. Here are the data.

Altitude: 2,240 feet
Temperature: 75 *F
Relative Humidity: no results
Pressure: 937.0 mb

Altitude: 2,552 feet
Temperature: 64 *F
Relative Humidity: no results
Pressure: 917.6 mb

I am in the process of rebuilding the UAVSonde weather station. Good thing, because it appears the relative humidity sensor has failed and I need to recalibrate the pressure sensor.

Wednesday, March 1, 2017

February Weather for NearSys Station

February was a much drier month than January. Far less snow this month. Temperatures are definitely on the rise. Still very brown and barren outside.

Sunday, February 26, 2017

Weather in Owyhee Moutains

My daily walk and a drive to town, gave me two opportunities to see weather in the Owyhee Mountains (the mountain range south of NearSys Station).

A snowstorm in the Owyhees
Fog near the base of the Owyhees

Saturday, February 25, 2017

UAVSonde for NearSys Station, 25 February 2017

The pressure sensor was recalibrated this week at the Boise Airport. The National Weather Service reports the air pressure hourly and converts it to sea level pressure for aircraft. I did not make an adjustment for the local temperature, so I will need to recalibration again some time. Afterwards, I will investigate how temperature affects the readings from the pressure sensor I'm using.

UAVSonde data were collected at 11:00 AM. Here are the data.

Altitude: 2,303 feet
Temperature: 40 *F
Relative Humidity: too cold to measure
Pressure: 929.5 mb

Altitude: 2,621 feet
Temperature: 36 *F
Relative Humidity: too cold to measure
Pressure: 916.9 mb

Friday, February 24, 2017

Balloon Launch for the Earth Science Classes at the Treasure Valley Math and Science Center

Friday, February 24th was partly spent launching two weather balloons for my school's earth science class. Currently the students are in the meteorology unit and a balloon launch and UAVSonde flight were perfect activities. One launch took place in the late morning and the second one in the early afternoon. The payload for this launch was a bag of student-made paper airplanes. Students put their names on the planes they made. Contact information for the school was printed on the airplane in case it was found again. A second, smaller balloon acted as the altitude switch that would open the bag carrying the paper airplanes.

The first launch took place in clear skies. So the students watched the balloon climb for about three minutes, or when it reached an altitude of 3,600 feet AGL. The balloon was observed drifting in the southeast direction, indicating winds were from the northwest.
The morning Earth Science class getting ready to start the countdown.
The second launch took place after puffy cumulus clouds had appeared. Students observed that the weather balloon disappeared in a cloud 2 minutes 45 seconds after launch. This length of time indicated the cloud base was at an altitude of 3,300 feet AGL. Students saw the balloon again about 10 minutes after launch, or at 12,000 feet AGL. This time the balloon had moved further north and heading generally in that direction. The second observation showed students that the winds were blowing in a different direction at that altitude.

The second balloon on its way to a cumulus cloud

Following the balloon launches, I sent up a UAVSonde and collected weather data. Here are the data from those flights.

Morning UAVSonde
Altitude: 2,426 feet
Temperature: 36 *F
Relative Humidity: too cold to measure
Pressure: 916.9 mb

Morning UAVSonde
Altitude: 2,916 feet
Temperature: 29 *F
Relative Humidity: too cold to measure
Pressure: 913.1 mb

Afternoon UAVSonde
Altitude: 2,588 feet
Temperature: 43 *F
Relative Humidity: 18%
Pressure: 918 mb

Afternoon UAVSonde
Altitude: 2,818 feet
Relative Humidity: 24%
Pressure: 912.4 mb

This was a fun pair of launches and reinforced how great this would be to do for a living and not just a hobby.

Thursday, February 23, 2017

Fun with Electrostatics Class, day 2

On the second day, Students learned about the Electrophorus and Leyden Jar. The Electrophorus was popularized by Alessandro Volta and is a pertpetual source of electrostatic charge (or at least until its insulating base loses charge). The Leyden Jar was developed by several people, one of them working at the University of Leyden (Pieter Musschenbroek). The Leyden Jar is a storage device. One can add charge to it to increase the charge stored in it.

So after building both devices, Students taking the Fun with Electrostatics class used the Electrophorus to generate a charge and then added that charge into the Leyden Jar. A shock from an Electrophorus is mild, but the shock from the Leyden Jar is very strong after adding charge from the Electrophorus ten times!

That's another charge added to the Leyden Jar

Monday, February 20, 2017

The Growth and Evolution of a Cloud in Three Parts, visible, near infrared, and thermal infrared

I put together a 80 second time-lapse video of a cloud east of NearSys Station. The images were recorded using the BalloonSat Imager that I am developing. The BalloonSat was turned on its side and programmed to record images with its three cameras every few seconds.

The video is now online at my YouTube Channel at,

The resulting video shows the cloud first in visible light. That way viewers can get their bearing. The near infrared image penetrates the atmosphere so well that details in the cloud are much sharper. The final portion of the video shows the cloud during the same time frame, but in heat images.

One thing to note is how the small cumulus cloud that popped up before the cumulonimbus is cooler than the cold stratus cloud above the cumulonimbus.

Here are three screen shots to help illustrate this.

Color Image

Near Infrared Image

Thermal Infrared Image

Sunday, February 19, 2017

UAVSonde for NearSys Station, 19 February 2017

UAVSonde data were collected at 7:10 AM. Here are the data.

Altitude 2260 feet
Temperature 36 *F
Relative Humidity 100%
Pressure 1002.9 mb

Altitude 2637 feet
Temperature 40 *F
Relative Humidity 100%
Pressure 985.0 mb

Thursday, February 16, 2017

Fun with Electrostatics Class: Day 1

The first day of Fun with Electrostatics taught students the history of electrostatics (briefly), the background on the nature of electrostatic charge, and the triboelectric series. The students then did basic experiments to reinforce what they were taught. These experiments included charging objects by friction, polarization, and conduction and seeing that like charges repel each other.

Kurt levitating a plastic ring using only electrostatic charge.
It's science magic! 

Monday, February 13, 2017

Great Horned Owl

On many of my recent evening walks, I have caught the hooting call of two Great Horned Owls. I have even managed to catch sight of one of them. This evening's walk was a little different in the owl decided to stay in place as I used my cellphone camera to get a picture of him or her.

Ever get the feeling you're being watched?

Sunday, February 12, 2017

A modification to the BalloonSat Recording Photometer expanded it's capabilities to function as a Photopolarimeter. A Photopolarimeter is a device to measure the intensity of light in different wavelengths and their amount of polarization. Most people are familiar with the fact that the brightness of light varies throughout the day, but not to the fact that the sky polarizes sunlight and how it can change throughout the day. The images below show how sky brightness varies as a Polaroid filter is rotated 90 degrees.

The experiment run at NearSys Station on February 11, 2017 was an attempt to detect both changes in polarization and intensity of sunlight in the eight different spectral bands listed below.

Infrared (940 nm)
Infrared (890 nm)
Red (660 nm)
Orange (620 nm)
Yellow (595 nm)
Green (505 nm)
Blue (470 nm)
Violet/UV (400 nm)

Polarization was measured in the North-South direction and then the East-West direction by comparing the intensity of sunlight in the above eight spectral bands as a polarizing filter was rotated over the light sensors. During the experiment, the Photopolarimeter was pointed due south and at an elevation of close to 45 degrees.

Sunrise occurred at 7:48 AM and sunset at 6:11 PM (18:18 hours). The sun was due south at 1:00 PM (13:00 hours). The sun's elevation at 1:00 PM was 32.5 degrees.

The Photopolarimeter slipped at 2:17 PM (14:17 hours) and remained pointing up until corrected at 2:41 PM (14:41 hours). However, the angle the Photopolarimeter was reset to was slightly lower in elevation that before.

Here are some things to notice.

1. From sunrise to 10:00 AM, sunlight has greater polarization in the East-West direction than North-South direction. At 10:00 AM, the sun was located at an azimuth of 133 degrees (southeast) and elevation of 19.5 degrees.

2. From 10:00 AM to 1:00 PM, sunlight has greater polarization in the North-South direction than the East-West direction. At 1:00 PM, the sun was located at an azimuth of 180 degrees (south) and elevation of 32.5 degrees.

3. From 1:00 PM to 4:15 PM, sunlight has greater polarization in the East-West direction than North-South direction. At 4:15 PM, the sun was located at an azimuth of 230 degrees (southwest) and elevation of 17.2 degrees.

4. After 4:15 PM, sunlight has no preferential polarization.

5. The amount of polarization is greatest at yellow (595 nm) and weakest at infrared (940 nm and 890 nm) and violet/UV (400 nm).

6. The intensity of red (660 nm) and infrared (890 nm and 940 nm) spiked from 5:35 PM to sunset. This peak was not observed in any other colors. At 5:35 PM, the sun was located at an azimuth of 246 degrees (west-southwest) and elevation of 6 degrees.

The Photopolarimeter will run several more days, weather permitting. The next experiment will involve placing the Photopolarimeter straight up. Later, the experiment will be run a third time with the Photopolarimeter pointing at the horizon. Later experiments will point it to the north.

An Update
After a discussion with Mr. Forrest Mims, I came to realize that Polaroid film is designed to be most effective at particular wavelengths. Since the Polaroid film I used is designed for eyeglasses, it should be more effective in the green-yellow portion of the electromagnetic spectrum (where human eyes are most sensitive). That may explain the greater polarization seen by the green and yellow LEDs.

Photons in the blue end of the spectrum have wavelengths so short that they can pass through the Polaroid film in either vibration orientation. Photons in the red end have wavelengths so large they can't be effected by the Polaroid film.

So off to find new polarization films.

You can read what Mr. Mims is up to at his website,