ARISSat-1/KEDR Goes Silent

Reception reports indicate that ARISSat-1/KEDR has stopped transmitting on Wednesday, January 4, 2012. The last full telemetry captured and reported to the ARISSatTLM web site at 06:02:14 UTC on January 4 were received from ground stations as the satellite passed over Japan. You can view the full telemetry display or the condensed telemetry display. Telemetry reports showed that the temperature aboard ARISSat-1/KEDR had been rising as atmospheric drag began to affect the satellite. Final temperatures received via ARISSatTLM reported this data:

IHU 75 ° C / 167.0 °F

PSU 76 ° C / 168.8 °F

RF 88 ° C / 190.4 °F

Control Panel 61 ° C / 141.8 °F

Experiment 64 ° C / 147.2 °F

Tracking data from Space Command gave a Predicted Decay Time 0700 GMT +/- 3 Hours on January 4. Telemetry report narrows the impact time window to about 4 hours. The predicted decay location is 12.7° S, 354.3° E, an open part of the South Atlantic, well west of Angola. Send reports to the amsat-bb If you heard the satellite, even briefly, after 0600 UTC. This will help confirm the actual impact point. Stations receiving telemetry from ARISSat-1 at any time over the last few months, please forward all of your .CSV telemetry files to telemetry AT arissattlm.org. Konstantin, RN3ZF sent a reception report of his copy of the 0842 UTC pass that, "the telemetry was absent, voice messages were not legible, very silent and interrupted. Most likely, I saw last minutes in the life of the satellite." Dee, NB2F reported, "Nothing heard from ARISSat-1/KEDR on any frequency during the first USA pass at 16:00 UTC, January 4." ARISSat-1/KEDR was deployed from the International Space Station on August 3, 2011 during during EVA-29 on by Cosmonaut/Flight Engineers Sergei Volkov and Alexander Samokutyaev.

 

The satellite carried a student experiment from Kursk State University in Russia which measured atmospheric density. Students from around the world provided the voices for the FM voice announcements. The amateur radio payload aboard ARISSat-1/KEDR achieved many "firsts" for amateur radio in space:

First flight test of AMSAT Software Defined Transponder which transmitted simultaneous:

FM voice downlink cycling between student messages, spoken telemetry and SSTV from cameras on the spaceframe.

16KHz bandwith linear transponder,

CW beacon with telemetry and callsigns of radio amateurs noting their significant contributions to amateur radio in space.

Robust, forward error corrected 1K rate BPSK downlink with satellite telemetry and Kursk experiment telemetry.

Development and release of the ARISSatTLM software for PC and Mac platforms enabled amateur stations worldwide with reliable reception of the BPSK telemetry, CW telemetry, display on the station's computer, and automatic upload of received data via the internet to the ARISSat engineering team. A new Integrated Housekeeping Unit was developed and successfully flown. A new Power Management System was developed and successfully flown.

AMSAT President Barry Baines, WD4ASW noted, ARISSat-1/KEDR marked a new type of satellite which has captured the attention of the national space agencies around the world for the unique educational opportunity we have been able to design, launch, and operate. By designing an educational mission aligned with NASA's Science, Technology, Engineering, and Mathematics goals amateur radio operators around the world have been able enjoy a new satellite in orbit." ARISSat-1/KEDR Project Manager, Gould Smith, WA4SXM said, "Dozens of amateur radio volunteers, AMSAT, ARRL, NASA, and Energia teamed up for this successful mission to bring you the most unique and innovative amateur radio satellite mission. Congratulations to all who made ARISSat-1 successful!"

ARISSat-1 altitude is rapidly decreasing

On Tuesday 27 Dec 2011 ARISSat-1 was losing about 4.1 km (~2.5 miles) a day in altitude, by Friday 30 Dec 2011 the decay was 5.9 km (3.6 miles) per day. This rate will continue to increase over the next days and ultimately result in the satellite burning up in the atmosphere. Telemetry reports haven't shown a large increase in temperatures yet, please collect and report these values during each illumination period. There have been a number of people that continue to update their calculations on when the satellite will re-enter. Dates range from 30 Dec to 16 Jan.

The fall rate dh/dt is  increasing dramatically. Be sure to do daily updates of the ARISSat-1/RadioSkaf-B Keps from Celestrak.com. The ARISSat-1 orbit changes daily while the satellite continues to lose altitude.
Roland, PY4ZBZ from Brazil has updated graphs of height and fall rate on his Web site:
 
Gould, WA4SXM

Last chances to hear ARISSat-1 are rapidly approaching.

A reminder that if you have been putting off working through the ARISSat-1 repeater, receiving SSTV pictures, or submitting telemetry, the next few weeks will be your last opportunity to be a part of this satellite's history.  Since deployment in August, ARISSat-1 has descended about 60 km, and is currently losing more than 1.5 km per day.  The rapid rate is partially the result of the recent solar activity on the atmosphere, significantly increasing the drag.  The predictions by several individuals and groups are all converging toward a reentry in January or February, 2012.

Heating will become significant before then. Remember, good telemetry in this period provides invaluable information to the engineering team, to be used in future projects.

The orbit period changes about 30 seconds per day, and that will increase steadily. Be certain to update your tracking program Keps from Space-Track or CelesTrak before each pass. They issue revised versions 3-5 times daily. As the descent continues, this will become even more critical to copying the telemetry beacon, especially unattended.

73s,

Alan

WA4SCA

Get Ready for the CW Contest

The ARISSat-1 mission is to provide a variety of information through its many broadcast modes promoting STEM based education initiatives in the classroom.  One of its modes is CW transmission.  CW stands for "continuous wave" and is transmitted in Morse Code.  To entice student interest in receiving Morse code, a CW contest has been created and all listeners are invited to participate.  Read more here.

ARISSat-1 Operation Survery

We’ve created an ARISSat-1 Operation Survey on Survey Monkey, please take a few minutes to take our survey.

Click here to take the survey

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Arissat 1 - KEDR

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Arissat 1 missions

Arissat 1 call sign: RS01S

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SUITSAT 1

 

SuitSat (also known as Mr. Smith,Ivan Ivanovich,RadioSkafRadio Sputnik, andAMSAT-OSCAR 54) is a retired RussianOrlan spacesuit with a radio transmittermounted on its helmet. SuitSat-1 was deployed in an ephemeral orbit around theEarth on February 32006. The idea for this novel OSCAR satellite was first formally discussed at an AMSATsymposium in October 2004, although theARISS-Russia team is credited with coming up with the idea as a commemorative gesture for the 175th anniversary of the Moscow State Technical University.

 

Lou McFadin, W5DID, heads the SuitSat-2 hardware team.

 

SuitSat-1 was launched into space from the ISS in February 2006. [NASA Photo]

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