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APRS The Automated Packet Reporting System by: Andy Zwirko - K1RA

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1 APRS The Automated Packet Reporting System by: Andy Zwirko - K1RA k1ra@k1ra.ushttp://www.k1ra.us/

2 Presentation Overview Definition, purpose and scope of APRS Definition, purpose and scope of APRS APRS Pitfalls & Misconceptions APRS Pitfalls & Misconceptions History of APRS and its inventor History of APRS and its inventor Station Hardware Station Hardware Network and data flow Network and data flow APRS protocol and raw packet decodes APRS protocol and raw packet decodes Software Software FARA members on APRS FARA members on APRS The future of APRS and opportunities The future of APRS and opportunities Links Links

3 What is APRS? APRS = Automatic Packet Reporting System APRS = Automatic Packet Reporting System APRS is an open system that uses unconnected AX.25 radio packets to transmit and collect data. APRS is an open system that uses unconnected AX.25 radio packets to transmit and collect data. APRS data is usually overlaid on a map APRS data is usually overlaid on a map

4 APRS is: A two-way information exchange using radio A two-way information exchange using radio A one-to-many, unconnected packet protocol. A one-to-many, unconnected packet protocol. A tactical protocol designed for local RF use. A tactical protocol designed for local RF use. A protocol with many reporting capabilities. A protocol with many reporting capabilities. A protocol with SMS capabilities. A protocol with SMS capabilities. A protocol also adapted to the Internet. A protocol also adapted to the Internet. A protocol with extensive flexibility built-in. A protocol with extensive flexibility built-in. A protocol still under development. A protocol still under development.

5 Purposes of APRS Immediate digital information exchange between all participants in a local area or event. This includes: Immediate digital information exchange between all participants in a local area or event. This includes: Positions and status of all stations and objects (GPS) Positions and status of all stations and objects (GPS) Messages, Bulletins and Announcements Messages, Bulletins and Announcements Assist in Search and Rescue operations Assist in Search and Rescue operations Gather and track weather data and telemetry (satellite, remote) Gather and track weather data and telemetry (satellite, remote) DF bearings and signal strengths for quick transmitter hunting DF bearings and signal strengths for quick transmitter hunting RF Connectivity plots of all stations RF Connectivity plots of all stations Local OBJECTS on a common map display for all users Local OBJECTS on a common map display for all users Local Freqs, Nets, Meetings, Marathons, Races, Events Local Freqs, Nets, Meetings, Marathons, Races, Events Voice Alert Signal Finding Nets & Meetings Wx Info Field Data Traffic Frequency RF Ranging

6 APRS Network Nodes Home stations Home stations Mobile and Portable GPS tracker stations Mobile and Portable GPS tracker stations Automatic Weather Stations Automatic Weather Stations Digipeaters Digipeaters Internet I-Gates Internet I-Gates

7 Scope of APRS

8 APRS Pitfalls & Misconceptions That APRS is just Vehicle Tracking vs. a Real-Time Information Distribution System. That APRS is just Vehicle Tracking vs. a Real-Time Information Distribution System. That APRS is dependent on GPS for its value (GPS is not needed. See Objects). That APRS is dependent on GPS for its value (GPS is not needed. See Objects). Failure to use the APRS built-in Mile-Marks for tracking all other non-APRS mobiles. Failure to use the APRS built-in Mile-Marks for tracking all other non-APRS mobiles. Using APRS clients that only do maps and ignore many of the APRS fundamentals. Using APRS clients that only do maps and ignore many of the APRS fundamentals. Failure to understand the importance of Objects Failure to understand the importance of Objects Not understanding the APRS operator’s role as a Data Input (Objects, Messages, etc) Not understanding the APRS operator’s role as a Data Input (Objects, Messages, etc) Failure to use real-time messaging: Failure to use real-time messaging: Not using the D7 and D700 as data entry and clipboard display units at field events. Not using the D7 and D700 as data entry and clipboard display units at field events. Too much focus on Large Screen Displays vs. Individual Operator displays for events. Too much focus on Large Screen Displays vs. Individual Operator displays for events. Failure to display APRS symbols with all their attributes and colors Failure to display APRS symbols with all their attributes and colors Failure to manage the network by adjusting a local digipeater for the situation at hand. Failure to manage the network by adjusting a local digipeater for the situation at hand. Not realizing the importance of Voice Operating frequencies in APRS. Not realizing the importance of Voice Operating frequencies in APRS. Failure to implement the original APRS Centralized Common Bulletin Board concept. Failure to implement the original APRS Centralized Common Bulletin Board concept. Ignore the fundamental Decay Algorithm to accelerate new data, and decay old data! Ignore the fundamental Decay Algorithm to accelerate new data, and decay old data!

9 Founder & History Bob Bruninga, WB4APR is considered the “Father of APRS” and is still active on a daily basis. Bob is a member of the United States Naval Academy Aerospace Engineering Dept. APRS was developed in the early 1990's for local tactical digital communications, situational awareness and TWO-WAY information exchange using Amateur radio. Bob Bruninga first used to track horses in 1994 Designed to “be a cost effective mapping program that would allow positioning of mobile stations using GPS receivers.”

10 What is needed to participate? Operating via RF Operating via RF Radio - VHF transceiver and antenna Radio - VHF transceiver and antenna TNC - Terminal Node Controller TNC - Terminal Node Controller Computer with APRS software installed Computer with APRS software installed GPS (optional) for mobile stations GPS (optional) for mobile stations Operating via the Internet Operating via the Internet Computer with browser or APRS software Computer with browser or APRS software Mobile phone with browser or APRS software Mobile phone with browser or APRS software

11 VHF Transceiver Any 2 meter radio will work as long as it will work on 144.390 carrier squelch Any 2 meter radio will work as long as it will work on 144.390 carrier squelch You will need to make a cable to connect mic audio, RX audio, and PTT to the TNC You will need to make a cable to connect mic audio, RX audio, and PTT to the TNC

12 TNC Encode/Decode Known as a radio modem, converts the digital information from the computer and/or GPS into audio tones and AX.25 Known as a radio modem, converts the digital information from the computer and/or GPS into audio tones and AX.25 The APRS network runs at 1200 baud The APRS network runs at 1200 baud

13 TNC Encode (only) Cheaper than a regular TNC ($30-45) but it only transmits data Cheaper than a regular TNC ($30-45) but it only transmits data Has a single port that only allows connection to a GPS Has a single port that only allows connection to a GPS Tiny Trak 3 Open Tracker 1+

14 APRS Enabled Radios Some radios have built in TNCs for direct connection to a computer or APRS interaction right on the display. Some radios have built in TNCs for direct connection to a computer or APRS interaction right on the display. Alinco DR-135Kenwood TH-D7AKenwood D-700A

15 GPS Receivers Uses military controlled GPS satellites available to general public Typical positions accuracy ranges from 1-5 feet GPS must output NMEA to work with APRS Many models available for under $100 Serial, USB, Bluetooth interfaces available to PC

16 Station Configurations Dedicated APRS system Dedicated APRS system GPS GPS Computer Computer Radio (separate) Radio (separate) TNC (encode/decode) TNC (encode/decode) Mic-E APRS system Mic-E APRS system Radio (shared) Radio (shared) TNC (encode only) TNC (encode only) GPS GPS

17 Dedicated Equipment Pros / Cons Pros Pros Can watch other units on map and send messages Can watch other units on map and send messages Position is sent out at predetermined intervals Position is sent out at predetermined intervals Separate radio system in car in case your 2M voice radio dies Separate radio system in car in case your 2M voice radio dies Separate radio infrastructure in case your repeater goes down Separate radio infrastructure in case your repeater goes down Could also be used as Winlink or Packet station Could also be used as Winlink or Packet station Cons Cons Another radio in the car Another radio in the car More 2M RF to interfere with your local repeater traffic More 2M RF to interfere with your local repeater traffic Higher cost because of more equipment Higher cost because of more equipment

18 Mic-E Pros and Cons Pros Pros Don’t have to install another radio in the car Don’t have to install another radio in the car Cheaper than the dedicated equipment way Cheaper than the dedicated equipment way Can use the cheaper encode only TNC Can use the cheaper encode only TNC Cons Cons Can not track other units on a map Can not track other units on a map Can not send messages to other units Can not send messages to other units Position only goes out when you talk on the radio Position only goes out when you talk on the radio Position on map could be very old since you didn’t talk on radio Position on map could be very old since you didn’t talk on radio More expensive for the repeater owners More expensive for the repeater owners Won’t work on all repeater systems Won’t work on all repeater systems No back-up radio if your voice radio fails No back-up radio if your voice radio fails If the repeater fails, no one sees your position If the repeater fails, no one sees your position

19 Home / Fixed System APRS Home Station without a GPS APRS Home Station without a GPS Radio TNC Computer

20 Trackers (one-way) Trackers have no APRS data display. So the receiver should be tuned to a beaconed Voice frequency so the operator can be involved in the Net! One-way trackers are good for non-manned assets at large movement events.. Not as the only APRS asset for a ham. One-way APRS is not normally recommended. APRS is a Network. We want good communications among all participants for maximum utility.

21 Tracker System Portable tracker box, with no compute or display Portable tracker box, with no compute or display GPS2m Antenna TrackerRadio

22 APRS Network Nodes Stations Stations Home Home Mobile Mobile Digipeaters Digipeaters Satellites Satellites I-Gates I-Gates APRS is a Network intended for real-time, two-way tactical information exchange.

23 SSID Suggestions Special Station Identifier (SSID) allows multiple stations with the same callsign to coexist on the network No SSID - Home Station, Home Station running I-Gate -1 Digipeater, Home Station running a Wide1-1 Digi, WX Digipeater -2 Digipeater [#2 or] on 70CM -3 Digipeater [#3] -4 HF to VHF Gateway -5 I-Gate (Not home station) -5 I-Gate (Not home station) -6 is for Operations via Satellite -7 Kenwood D7 HH -8 is for boats, sailboats and ships (maybe 802.11 in the future) -9 is for Mobiles -10 is for operation via the internet only -11 is for APRS touch-tone users (and the occasional Balloons) -12 Portable Units such as Laptops, Camp Sites etc. -14 is for Truckers -15 is for HF -15 is for HF

24 Digipeaters Extend the coverage of the portable and mobile units Extend the coverage of the portable and mobile units Much like a repeater but operating on a simplex frequency. Much like a repeater but operating on a simplex frequency. Usually located at a high location on a tower Usually located at a high location on a tower Can also be located at someone’s home to help fill in a certain area. Can also be located at someone’s home to help fill in a certain area.

25 Paths WIDEn-N vs. Named Digipeaters acknowledge WIDEn-N paths Digipeaters acknowledge WIDEn-N paths WIDEn-N paths are decremented for each hop WIDEn-N paths are decremented for each hop Never need more than WIDE2-2 Never need more than WIDE2-2 Named path most efficient form of message propagation Named path most efficient form of message propagation Only the station with the matching Alias will digipeat the message Only the station with the matching Alias will digipeat the message WD4HDL-1, N3HF-1 WD4HDL-1, N3HF-1

26 I-Gates – Tier2 Global Net I-Gates are internet gateways that expand the reach of APRS worldwide – www.aprs2.net I-Gates are internet gateways that expand the reach of APRS worldwide – www.aprs2.netwww.aprs2.net An I-Gate listens to the local RF channel and relays the information into an APRS Internet data stream. An I-Gate listens to the local RF channel and relays the information into an APRS Internet data stream. I-Gates also relay information from the Internet data stream to a local RF station I-Gates also relay information from the Internet data stream to a local RF station

27 Benefits of I-Gates Reduces RF network congestion Reduces RF network congestion Increases the trackability of mobile stations Increases the trackability of mobile stations Allows RF access of weather service bulletins and alerts Allows RF access of weather service bulletins and alerts Can set up an APRS station without a radio and TNC Can set up an APRS station without a radio and TNC Any APRS station can be queried at www.findu.com or www.aprs.fi Any APRS station can be queried at www.findu.com or www.aprs.fi www.findu.comwww.aprs.fi www.findu.comwww.aprs.fi

28 Typical Local APRS Network Internet Gateway Digipeater Home Fixed Digipeater Portables Mobiles

29 APRS Data Flow

30 APRS Protocol

31 APRS Data Types

32 APRS Position Protocol

33 APRS Object Protocol

34 APRS Message Protocols

35 APRS Map Symbols

36 Raw APRS Packets

37 Decoded APRS Packets Location and Status

38 Decoded APRS Packets Location and weather report

39 APRS Software PC Clients PC Clients APRSDos APRSDos WinAPRS/MacAPRS WinAPRS/MacAPRS UI-View UI-View APRSpoint APRSpoint APRS+SA APRS+SA Xastir (Linux / Unix) Xastir (Linux / Unix) Internet Browser Internet Browser PDA Clients PDA Clients AprsCE AprsCE APRS-Go APRS-Go APRS-Palm APRS-Palm I-Gate I-Gate JavAPRS JavAPRS AHub AHub aprsD aprsD NOSaprs NOSaprs

40 APRSDos The original APRS application. Development going back to 1992 The original APRS application. Development going back to 1992 Very rudimentary maps Very rudimentary maps Has satellite tracking features, network utilization analysis, and direction finding support Has satellite tracking features, network utilization analysis, and direction finding support Price – free Price – free http://www.usna.edu/Users/aero/bruninga/ap rs.html http://www.usna.edu/Users/aero/bruninga/ap rs.html http://www.usna.edu/Users/aero/bruninga/ap rs.html http://www.usna.edu/Users/aero/bruninga/ap rs.html

41 APRSDos

42 WinAPRS Uses USGS Tiger maps and integrates with Precision Maps from Undertow Software Uses USGS Tiger maps and integrates with Precision Maps from Undertow Software Also uses old style APRSDOS vector maps. Also uses old style APRSDOS vector maps. NWS weather data overlay capability NWS weather data overlay capability Price – free Price – free http://www.winaprs.com http://www.winaprs.com http://www.winaprs.com Also hosts X-APRS, MacAPRS, dosAPRS Also hosts X-APRS, MacAPRS, dosAPRS

43 WinAPRS

44 UI-View Lots of features, more complex interface Lots of features, more complex interface Handles plug-ins (ex: NWS radar, Sat. telemetry) Handles plug-ins (ex: NWS radar, Sat. telemetry) Vibrant developer network Vibrant developer network Uses user generated, or raster maps. Uses user generated, or raster maps. Integrates with Precision maps. Plug-ins for Street Atlas, Mapblast and Tiger Maps Integrates with Precision maps. Plug-ins for Street Atlas, Mapblast and Tiger Maps Price – free Price – free http://www.uiview.org http://www.uiview.org http://www.uiview.org

45 UI-View

46 UI-View

47 APRSpoint Easy to use, familiar Microsoft style interface Easy to use, familiar Microsoft style interface Requires MapPoint 2004, 2006, 2009 or 2010 Requires MapPoint 2004, 2006, 2009 or 2010 Provides for routing Provides for routing Price – $77 with maps, $47 without maps Price – $77 with maps, $47 without maps http://www.aprspoint.com http://www.aprspoint.com http://www.aprspoint.com

48 APRSpoint

49 APRS+SA Interfaces with Delorme Street Atlas USA Interfaces with Delorme Street Atlas USA Offers text-to-speech capabilities Offers text-to-speech capabilities Price - free Price - free

50 APRS-Go Windows Mobile / PDA Windows Mobile / PDA Uses OSM public map set Uses OSM public map set Works with many TNCs Works with many TNCs Price – free Price – free PC version too PC version too http://www.aprsgo.com/

51 Online APRS Resources While APRS is intended to be a primary network that does not require the Internet, many users use online national databases to track stations

52 APRS Real Time Propagation http://www.mountainlake.k12.mn.us/ham/aprs

53 www.APRS.fi - Mapping

54 www.APRS.fi - Weather

55 www.APRS.fi - Beacons

56 www.findU.com - Mapping

57 www.findU.com – Nearby-In Range Google for “USNA Buoy” Select USNA-1

58 www.findU.com - Messages

59 FARA on APRS KX4O – John – Mobile Tracker & Golden Packet KX4O – John – Mobile Tracker & Golden Packet W4IFI – Randy – Mobile Tracker & Wx W4IFI – Randy – Mobile Tracker & Wx KD6AKC – Mark – Mobile Tracker KD6AKC – Mark – Mobile Tracker N4YXW – Chuck – Internet Gateway N4YXW – Chuck – Internet Gateway KW4VA – Andy (K1RA) – Echolink gateway KW4VA – Andy (K1RA) – Echolink gateway

60 APRS Golden Packet 2010

61

62

63 Future of APRS International Space Station (ISS) The ISS was equiped with an APRS receiver on 145.825 recently The ISS was equiped with an APRS receiver on 145.825 recently Used for crew to send messages to friends, family, and amateur radio operators Used for crew to send messages to friends, family, and amateur radio operators Designed to track ISS in space Designed to track ISS in space Used as a space digipeater in the APRS space satellite constellation Used as a space digipeater in the APRS space satellite constellation More info at www.ariss.net More info at www.ariss.net www.ariss.net

64 APRS Satellite Tracking & Reporting System ASTARS - http://www.aprs.org/astars.html ASTARS - http://www.aprs.org/astars.htmlhttp://www.aprs.org/astars.html

65 APRS Opportunities APRStt (APRS touchtone decoding) APRStt (APRS touchtone decoding) Simple DTMF memory Simple DTMF memory One button reports Position, Freq. and Status One button reports Position, Freq. and Status On every voice repeater On every voice repeater On every IRLP node On every IRLP node On every Echolink node On every Echolink node Any where on.52!! Any where on.52!! ONLY NEEDS local software upgrade ONLY NEEDS local software upgrade AVRS (Automatic Voice Relay System) Global VOIP via APRS AVRS (Automatic Voice Relay System) Global VOIP via APRS Uses APRS message to set up call Uses APRS message to set up call Automatically links to Echolink or IRLP Automatically links to Echolink or IRLP Radio auto-QSY’s to make link (Ham Radio Cell phone from Mobile) Radio auto-QSY’s to make link (Ham Radio Cell phone from Mobile)

66 Simple DTMF memory - One button puts you in APRS ( Position, Frequency and Status )! Simple DTMF memory - One button puts you in APRS ( Position, Frequency and Status )! DTMF on voice freq translated to packet on APRS channel (or direct to APRS-IS) DTMF on voice freq translated to packet on APRS channel (or direct to APRS-IS) Position is 10 mile ambiguity using repeater posit ( or 60 mile ambiguity out west ) Position is 10 mile ambiguity using repeater posit ( or 60 mile ambiguity out west ) Frequency in packet is Frequency of Repeater Frequency in packet is Frequency of Repeater If Echolink or IRLP, APRS packet includes node number! If Echolink or IRLP, APRS packet includes node number! APRStt (Touchtone)

67 For WB4APR, the DTMF Sends: #A922444427A77D For WB4APR, the DTMF Sends: #A922444427A77D This is converted to an APRS packet on the APRS channel as: This is converted to an APRS packet on the APRS channel as: WB4APR-11>APRStt,WIDE1-1:!DDM_.__N/DDDM_.__W$146.895MHz T107 IRLP7070WB4APR-11>APRStt,WIDE1-1:!DDM_.__N/DDDM_.__W$146.895MHz T107 IRLP7070 Puts you on global map near Baltimore Maryland, with your immediate calling frequency, your Tone and your IRLP node number. Puts you on global map near Baltimore Maryland, with your immediate calling frequency, your Tone and your IRLP node number. That is everything you need to be known to the Global APRS system! That is everything you need to be known to the Global APRS system! We have had this since 2001 (in DOS w DTMF chip). We have had this since 2001 (in DOS w DTMF chip). We need someone to do this with a sound card in windows? We need someone to do this with a sound card in windows? Build into every Echolink/IRLP node and every Repeater controller with a serial port! Build into every Echolink/IRLP node and every Repeater controller with a serial port! Unless we get APRStt and therefore 100% situational awareness of any Ham mobile or HT then APRS will always be a side show only used by 10% of any club or organization. Unless we get APRStt and therefore 100% situational awareness of any Ham mobile or HT then APRS will always be a side show only used by 10% of any club or organization. How about: #B95*234*2D => Milemark #234 on Route 95, northbound APRStt (Touchtone)

68 DTMF Report shows on APRS DTMF Report shows on APRS CALLSIGN with date and time CALLSIGN with date and time Position in vicinity of repeater or APRStt entry point Position in vicinity of repeater or APRStt entry point Voice Operating Frequency, Tone and other info Voice Operating Frequency, Tone and other info Node number if Echolink or IRLP, or reverse patch number if Repeater Node number if Echolink or IRLP, or reverse patch number if Repeater 147.105MHz T107 R30m APRStt (Touchtone)

69 As simple as adding a DTMF chip to a Micro-Trak Or adding a DTMF chip to an OT and HT for use in the field at a special event APRStt (Touchtone)

70 APRStt, maps and events That APRS is dependent on GPS for its value That APRS is dependent on GPS for its value (GPS is not required to put things on maps). (GPS is not required to put things on maps).

71 APRS Voice Alert! Voice Alert is effectively 3 rd Radio channel for the D7 and D700 APRS radios Voice Alert is effectively 3 rd Radio channel for the D7 and D700 APRS radios Set the APRS Band A to PL-100 Set the APRS Band A to PL-100 and keep the volume turned up: You wont hear any packets on 144.39 * You wont hear any packets on 144.39 * But you will hear a voice call using PL-100 on 144.39 But you will hear a voice call using PL-100 on 144.39 And you will hear* an occasional Ping packet if another D700 comes in line-of-site to you, like a proximity radar alerting you to local presence. And you will hear* an occasional Ping packet if another D700 comes in line-of-site to you, like a proximity radar alerting you to local presence. Great for long haul traveling and meeting other APRS users. Great for long haul traveling and meeting other APRS users.

72 Links WB4APR – APRS Home - http://www.aprs.org/ WB4APR – APRS Home - http://www.aprs.org/http://www.aprs.org/ APRS Protocol – APRS Protocol – ftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdf ftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdfftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdf ftp://www.tapr.org/aprssig/aprsspec/spec/aprs101m/ ftp://www.tapr.org/aprssig/aprsspec/spec/aprs101m/ftp://www.tapr.org/aprssig/aprsspec/spec/aprs101m/ APRS Info Wiki – http://info.aprs.net/ APRS Info Wiki – http://info.aprs.net/http://info.aprs.net/ APRSSIG Users Group – http://tapr.org/mailman/listinfo/aprssig APRSSIG Users Group – http://tapr.org/mailman/listinfo/aprssighttp://tapr.org/mailman/listinfo/aprssig APRS Apps - http://www.eskimo.com/~archer/aprs_capabilities.html APRS Apps - http://www.eskimo.com/~archer/aprs_capabilities.htmlhttp://www.eskimo.com/~archer/aprs_capabilities.html APRS-IS – Internet Spec Info - http://www.aprs-is.net/ APRS-IS – Internet Spec Info - http://www.aprs-is.net/http://www.aprs-is.net/ APRS Tier2 Network – http://www.aprs2.net APRS Tier2 Network – http://www.aprs2.nethttp://www.aprs2.net APRS.fi Map & Database – http://www.aprs.fi/ APRS.fi Map & Database – http://www.aprs.fi/http://www.aprs.fi/ OpenAPRS Map – http://www.openaprs.net/ OpenAPRS Map – http://www.openaprs.net/http://www.openaprs.net/ FindU APRS Map & Database – http://www.findu.com/ FindU APRS Map & Database – http://www.findu.com/http://www.findu.com/ APRS & Edge of Space Science – http://www.eoss.org/aprs APRS & Edge of Space Science – http://www.eoss.org/aprshttp://www.eoss.org/aprs APRS on ISS – http://www.usna.edu/Users/aero/bruninga/iss-faq.html APRS on ISS – http://www.usna.edu/Users/aero/bruninga/iss-faq.htmlhttp://www.usna.edu/Users/aero/bruninga/iss-faq.html APRS Balloons – http://www.aprs.org/balloon-n8pk.html APRS Balloons – http://www.aprs.org/balloon-n8pk.htmlhttp://www.aprs.org/balloon-n8pk.html PCSAT2 – http://www.usna.edu/Users/aero/bruninga/pcsat2.html PCSAT2 – http://www.usna.edu/Users/aero/bruninga/pcsat2.htmlhttp://www.usna.edu/Users/aero/bruninga/pcsat2.html Meteor Scatter – http://www.usna.edu/Users/aero/bruninga/meteors.html Meteor Scatter – http://www.usna.edu/Users/aero/bruninga/meteors.htmlhttp://www.usna.edu/Users/aero/bruninga/meteors.html


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