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Camera systems introduction

Temp Place holder

Camera systems currently in use by network members include the Sentinel camera a Sony, the Watec 902H, and the PC164CEX-2.

Sentinel camera:

The Sentinel III camera is a Sony HiCam HB-710E. The CCD (Charge Coupled Device) is a 1.27 cm (0.5 inch) interlined chip with 410K pixels. Effective Pixels 768 (Horizontal) X 494 (Vertical). It has a super-low illumination environment of 0.0005 Lux(F1.2 /20 IRE at AGC Max). It is powered by +12VDC and consumes 150 mA at maximum load.

The lens is Rainbow L163VDC4P fisheye lens with a 180 degree field.

For a pictorial tour of the Sony HiCam HB-710E camera, it’s housing and frame grabber click here.

The Sentinel – video frame grabber comes in an external box. It contains a micro-controller, a RCM3200, from Rabbit Semiconductor. There are three connections on the box, 1) +3.3V DC input, 2) a BNC male connector for the 1Vp-p video input from the Sony camera via 75 ohm coax, and 3) an Ethernet jack. The frame grabber communicates with a PC via the ethernet cable either directly with a crossover cable or through a LAN hub via a conventional ethernet cable.

The Sentinel III system is being replaced by the Sentinel IV system which uses the same camera but uses an internal Hauppaugue model 188 video  card.

Watec 902H

PC164CEX-2

acrylic domes from EZ Tops in New Brunswick.

fisheye lens, sources

 

Video Software systems

A place holder for discussing video software

Software systems:

Sentinel II

The Sentinel II was earliest of the Sentinel camera system used by the BCMN. It used a convex mirror with the camera above the reflecting mirror. Video was feed into a VCR. Users then scanned the nights catch the next day or when there was a report of a fireball.

Sentinel III

This system is still in use by many of the operators of the BCMN. The camera and associated hardware can be seen in a picture essay here Sentinel III system in photos. The system uses an external frame grabber which has firmware burned into a EPROM chip. The frame grabber has an IP address of 10.0.0.1 and communicates with the host computer via a Null type ethernet cable.

Pros:

  1. The software runs on very old, less capable computers without straining them.
  2. The software can run multiple platforms/systems as is.
  3. Software is written in a clear logical way and can be modified easily.
  4. Stable and will run for months at a time.

Cons:

  1. The external frame grabber takes time to download the capture to the software so some meteors are missed during this transaction.
  2. Frame grabber ties up an Ethernet port
  3. On some routers it is impossible to run a net time server due to the 10.0.0.# addressing or port loss.
  4. No stacking of images to bring out the stars. The make long exposure after event helps but is not that powerful.
  5. Shelf space taken up by external frame grabber, cable, and power supply cords.

Sentinel IV

Is the next generation in the Sentinel line. This system employs an internal video card; the Hauppauge ImpactVCB model 188 board.

The software is in beta testing so it is hard to list the pros and the cons. Many of the cons have been squashed in the last couple of upgrades. When fully developed the software is suppose to automatically ftp the events back to New Mexico where it will be analyzed. This feature has not been implemented as of yet.

Pros:

The biggest improvement is the near real time capture and data writing. There are no longer dead seconds (sometimes minutes) while the card downloads to the computer. This leads to much less loss of data during showers.  It does have a method to simulate stacking frames that helps define dimmer stars.

I see two cons so far. The first is the software’s dependence on Windows system software. I can not be run on Linux or Mac computers without going to a virtual machine and running Windows. I see this as a big step backwards although Window users will not be that impacted by the switch. The other con is the code is compiled so there is no way to easily read  or modify the source code.

It is too soon to tell how stable the final version of the software will be or what planned features will make the final cut.

 

UFOCapture

Unlike Sentinel software UFOCaptureV2 (V2.22  2008/11/28) is not freeware, it is a commercial product. There are two other sets of software that analyze the UFOCapture files, UFOAnalyzer V2 (V2.28 2010/02/28)  and UFO Oribit (V2.25 2010/02/28). They both are freeware and they will be covered in the Video Analysis section.

Pros:

  1. Works with multiple camera types.
  2. Highly flexible can fine tune to observer’s needs.
  3. Overlays a Time stamps on the video images.
  4. Easy to make masking
  5. Software notes and produces scintillation masks.
  6. Can fine tune the triggering and greatly reduce or eliminate aircraft, spiders, and bird triggers.
  7. Records more stars than Sentinel does during exposures.
  8. Multiple meteor capture possible
  9. Coupled with the two associate analysis software the trio gives the user a very powerful tool, especially with multi-station captures.

 

Cons:

  1. Needs a video to digital card like Canopus or the Hauppauge card that comes with Sentinel IV.
  2. Expensive license versus freeware and shareware.
  3. The manual was originally written in Japanese and the English translation is fairly choppy and hard to understand at times.
  4. Eats up a lot cpu cycles so a newer, faster and more capable computer is needed compared to a Sentinel system
  5. The software is so full of features it presents a steep learning curve before feeling at ease with it.

 

HandAvi

 

Note: Video Analysis software will be covered in the Analysis section of this site.

 

2009 11 08 Prince George Fireball

On November 8, 2009, Wayne, at RDL Observatory, reported a capture of a bright fireball to our network. He told us:

“All
Late night capture, direction of travel westward. Event seen at Telkwa BC. UFO analyzer places impact area some where in the Terrace / Telkwa area but calibration of ufo analyzer is uncertain.  Witness at Telkwa said phosphor like drops falling between him and hill 1 mile to his north.  No Sound heard. enjoy
wayne”

Wayne sent a movie of the event to the BCMN group. You can view it here:

 

Upon receipt of Wayne’s report Brower wrote Alan Hildebrand, Coordinator of the Canadian Fireball Reporting Centre, and asked if he was getting any additional reports of the event. He said he had not heard of the event.

In between e-mails Hildebrand checked back in his mail and found the alert Wayne had sent earlier. (It’s always  good to follow up if you don’t hear back).

CBC carried and article the next day. You can view the article by clicking here.

On November 9th Hidlebrand (personal communication to Brower) summarized to the MIAC group. The fireball was:

  1. Seen widely.
  2. It caused explosive booms and cast ground shadows.
  3. He estimated the fireball to be in the  -17 to -18 magnitude range.
  4. Estimate ‘conservatively in 100 kg to 1 tonne order of magnitude’.
  5. Had an east to west motion (and apparently some south to north and at least modestly steep) which would be reasonable for prefall orbits.
  6. Was probably a meteorite dropper.

No other BCMN camera recorded the fireball.

 

2008 09 09 The SPE Outbreak

As the sun was about to rise on September 9, 2008 an unpredicted outbreak of the September Perseid shower occurred.

Jeff, at the West Kelowna site, checked his overnight Sentinel video captures and quickly noted an unusual cluster of fireballs. Below is a composite image of of the outbreak.

Brower notified Dr. Peter Jenniskens of the large number of fireballs via e-mail. Jenniskens then sent inquiries to other observers to confirm the outbreak. Almost simultaneously reports of the outbreak started coming in on various meteor forums . As soon as Jenniskens received supporting information he issued a telegram, CBET 1501, as shown below.

CBET 1501 SPE 2008

 

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2008 02 19 PNW Bolide

On February 19, 2008 at 13:30 UT, a large fireball entered the earth’s upper atmosphere. Visual reports of the bolide started streaming in at police stations and television stations. A regional airline pilot filed a report of a possible aircraft going down over western Washington.

At 13:30:59 UT the West Kelowna Sentinel all-sky camera caught was triggered by a extremely bright bolide. The video showed the bolide moving slowly downward towards my southeastern horizon. It disappeared behind the mountains across the Okanagan Lake. Despite being below my horizon behind the mountain range the sky pulsed with light as the bolide went through several terminal bursts as can be seen by the total amplitude light curve produced by the Sentinel camera:

 

A look at the total number of pixels above the triggering threshold shows most of the light was released during it’s terminal flares.

Total Pixels graph

The graphs as well as the movie was sent to Dr. Alan Hildebrand, Coordinator of the Canadian Fireball Reporting Centre, University of Calgary.

 

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2006 06 A numerical method to aid

One of the biggest problem with forward scatter data is that each recording station is different from the others. One station might be using a highly directional yagi type antenna with it’s associated forward gain, while others might be using a simple vertical antenna. Others stations use a one wavelength closed loop, discones, or even quadafilar antennas. Each type of antenna places a certain bias on how many echoes are heard per hour.

In addition to the various antennas in use, radio observers also employ many different types of receivers. Some are state of the art while others are less sensitive and less selective than the more capable receivers. This again will influence the station’s daily data.

Yet an other variable among the stations it their frequency and transmitter choice. A few Japanese station listen to beacons on 28 MHz while several Europeans listen to the French satellite radar at 143.  Frequency choice and the transmitter’s output power  can greatly affect  a station’s data.

Recognizing this inter-station variability a few of us decided to attempt a numerical model to ‘level the playing field’ by using the concept of Observability Function. There will be follow ups to improve this initial modeling. It has been field tested and provides some hope on equalizing the data from such diverse stations.

The complete paper (WGN 34:3 p87-97) can be downloaded here.

 

2006 12 22 Outburst of Ursids

 

On December 22, 2006 The Ursid shower showed an above normal peak as reported by visual observers, all-sky video observers, and by radio observers. The outburst was predicted in CBET 77. The West Kelowna camera was under an overcast and did not record any captures. The radio data however did record earth passing through the predicted Ursid filament.

Here is the original telegram announcing our findings:

 

2006 01 04 The 2006 Quadrantids

The Quadrantid meteor shower is the first major shower of the new year. More importantly the shower is  a strong and reliable performer. It also happens to be one of the least observed stream of the major showers as early January usually produces low overcasting clouds whether you live in Asia, Europe or North America.

Unlike visual and video observers the low clouds and snow are no problem for radio observers. As the Quadrantid shower echo rates started increasing in West Kelowna, I started watching the live radio page at the RMOB site. I also visited the Japanese sites as well.

By observing these sites I could watch as the echo counts decreased in Europe as the radiant dipped downward, my numbers were on the increase. As mine were peaking the Japanese started seeing the radiant. As my data was taking hits from long duration, overdense echoes I made a note to see if I could make sense of the Quadrantid shower over both geographical space and through time.

I submitted my the results of my analysis to the editor of the WGN, the Journal of the International Meteor Organization. After being reviewed by others it was published. You can download a copy of the paper here.

 

 

2002 11 19 Leonids Outbreak

Hiroshi Ogawa, head of the International Project for Radio Meteor Observation,  asked radio detection stations from around the world to observe the Leonids during the period of November 1 to November 25, 2002.

Note: Brower was located in Loveland, Colorado at the time of the study and not in West Kelowna.

The following graph shows three stations located in Slovenia, USA, and Japan. The three stations data help trace  the overall activity of the 2002 Leonids.  Notice how as the radian lowered in the sky in Slovenia the radiant was rising for Colorado. Similarly, as the radiant dipped to the west of Colorado it was climbing higher in the sky in Japan, thus giving a continuous view of the overall stream activity over time.

FS Radio results Leo 2002

One of the most rewarding part of the 2002 Leonid study was the recording of a predicted filament  of the comet’s ejecta by Yrjöllä and Brower.

In chapter 14 of Jennniskens book, Meteor Showers and their Parents (Jenniskens 2006:201-215) gives a detail discussion of the filament and why it is important. He states:

Jupiter’s past perturbations may have responsible for the sudden onset of the component in 1994…
I expected the dust component would remain visible post perihelion for at least slightly less than one orbit of Jupiter (<12 yr), thus until 2004 or 2005.

I saw this validated in 2002, when the Filament component was detected for the first time after the perihelion passage of the comet, underlying two very narrow Leonid storm profiles (Fig. 14.41) The observed shift in the peak time and constant width over the years 1994 to 2002 (Table 4) confirms that this component moves about the earth’s path much like individual dust trails in reflection to the ever changing gravitational field of the planets (shaded area in Fig 14.15). Again, more or less following the sun’s reflex motion. (Ibid:214-215)

(Place Fig 14-41 Yrjöllä and Brower here)

More to come…

Jenniskens, P. 2006. Meteor Showers and their Parents, Cambridge University Press, Cambridge, U.K.