APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon. It woiuld be nice to get an assessment of the remaining lifetimes of the remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements and have not been paying attention.
Joe wanna take a crack at it? Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's atmosphere. Mean motion is now dangerously close to 16! Time for a Chicken Little contest?
de KM1P Joe
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a
Chicken Little contest?
de KM1P Joe
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a
Chicken Little contest?
de KM1P Joe
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a
Chicken Little contest?
de KM1P Joe
PLEASE!
All of you that are capable of trying to predict this re-entry, keep doing it.
I think it would be awesome if we were able to actually see it come back home!
Joe WB9SBD
On 12/2/2021 5:18 PM, ray.hoad@mypbmail.com wrote:
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available athttp://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21,ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bbamsat-bb@amsat.org Cc: Robert Bruningabruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed onhttp://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a Chicken Little contest?
de KM1P Joe
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available athttps://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences athttps://mailman.amsat.org
Special kudos to a QSO via meteor scatter on the remains! :-)
Burns WB1FJ
On Thu, Dec 2, 2021 at 6:22 PM Joe nss@mwt.net wrote:
PLEASE!
All of you that are capable of trying to predict this re-entry, keep doing it.
I think it would be awesome if we were able to actually see it come back home!
Joe WB9SBD
On 12/2/2021 5:18 PM, ray.hoad@mypbmail.com wrote:
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a
Chicken Little contest?
de KM1P Joe
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list athttps://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
is there a list of APRS Satellites still working I use to hear IO86, PSAT-2, and ISS but seems like it's rare now? *Thanks and 73* *Larry Fields: du1/n6hpx * *du1n6hpx@gmail.com du1n6hpx@gmail.com * *du1/n6hpx@qsl.net n6hpx@qsl.net * *144.110 USB 444.325 USB 145.200 FM* *Boxchip DMR Partner *https://boxchiptt.com/
On Sat, Dec 4, 2021 at 6:13 AM Burns Fisher wb1fj-bb@fisher.cc wrote:
Special kudos to a QSO via meteor scatter on the remains! :-)
Burns WB1FJ
On Thu, Dec 2, 2021 at 6:22 PM Joe nss@mwt.net wrote:
PLEASE!
All of you that are capable of trying to predict this re-entry, keep doing it.
I think it would be awesome if we were able to actually see it come back home!
Joe WB9SBD
On 12/2/2021 5:18 PM, ray.hoad@mypbmail.com wrote:
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a
Chicken Little contest?
de KM1P Joe
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list athttps://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
For accurate predictions with SatEvo you should use more than just the last TLE set. Use at least the last 10 to 15 TLE sets, plot those in a graph and calculate the average line through these predictions. That will give you a much more accurate decay prediction.
Btw SatEvo tends to predict the decay date too late when the decay is still several weeks in the future. Closer to the decay date the predictions will shift to earlier dates. Of course you should also use a good value for the solar flux. This value should not be the single value of one day, but it should be the average value over the last couple of weeks.
73, Nico PA0DLO
On 03-12-2021 00:18, ray.hoad@mypbmail.com wrote:
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a Chicken Little contest?
de KM1P Joe
Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Acceptable Use and Privacy Policies available at https://www.amsat.org/about-amsat/
View archives of this mailing list at https://mailman.amsat.org/hyperkitty/list/amsat-bb@amsat.org To unsubscribe send an email to amsat-bb-leave(a)amsat.org Manage all of your AMSAT-NA mailing list preferences at https://mailman.amsat.org
Thanks Nico for the helpful hints. My experience with SatEvo is limited and I was not aware of the hints that you listed.
Thanks!
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
-----Original Message----- From: Nico Janssen [mailto:hamsat@xs4all.nl] Sent: Friday, December 3, 2021 05:12 To: ray.hoad@mypbmail.com; 'Pedro Converso' pconver@gmail.com Cc: amsat-bb@amsat.org; bruninga@usna.edu Subject: Re: [AMSAT-BB] Re: APRS satellite Lifetimes?
For accurate predictions with SatEvo you should use more than just the last TLE set. Use at least the last 10 to 15 TLE sets, plot those in a graph and calculate the average line through these predictions. That will give you a much more accurate decay prediction.
Btw SatEvo tends to predict the decay date too late when the decay is still several weeks in the future. Closer to the decay date the predictions will shift to earlier dates. Of course you should also use a good value for the solar flux. This value should not be the single value of one day, but it should be the average value over the last couple of weeks.
73, Nico PA0DLO
On 03-12-2021 00:18, ray.hoad@mypbmail.com wrote:
I think that estimate may be close. Thanks Pedro for your comment.
I also have Satevo (V 0.51), but I want to wait until we are midway through December for Satevo to make a better estimate.
Ray Hoad WA5QGD AMSAT-NA Orbital Elements Manager
Ray, Bob, interesting comment,
Satevo predicts NO-84 reentry on Dec-31-2021 at 1:30z
Obj # Epoch Decay (Date) 15025D 40654 21329.440610 21365.054941 (2021 December 31)
Satevo available at http://amsat.org.ar/satevo.zip just needs last TLE file.
73, lu7abf, Pedro
On 12/2/21, ray.hoad@mypbmail.com ray.hoad@mypbmail.com wrote:
We still have some live left for NO-84 (PSAT), Cat ID 40654.
Based on past experience, when an amateur satellite’s drag rises above the 0.01 magnitude, the satellite is usually getting close to reentry. Some have climbed back up for a while. But, as a rule of thumb, 0.01 drag is the point I start watching a satellite’s drag. Almost all amateur satellites have a mean motion of at least 16 when they decay.
The current TLE shows NO-84 (PSAT), Cat ID 40654, with a drag of 0.00320060 and a mean motion of 15.99945301. Getting close.
For example, here are the drag values for a few satellites the day they deorbited:
SAT Cat ID drag Mean Motion
==================================================
NEPALISAT1 44331 0.04661449 16.30483242 RAVAANA 44329 0.04382427 16.28919678 UGUISU 44330 0.06186538 16.33294840 CP9 44360 0.01594744 16.12399308 TW-1C 40926 0.05243455 16.31196197 MO-105 44832 0.11453400 16.41416157 MO-106 44830 0.14504533 16.46538413 ENDURO SAT ONE 43551 0.12819970 16.45548142 EQUISAT 43552 0.10316869 16.43170683 SWAMPSAT 45115 0.19123998 16.36852634 PWSAT 2 43814 0.25888781 16.21683976
Per above, several have hung on for another order of magnitude of
drag. It would be very difficult to estimate a deorbit time based solely on drag. But, all have had a mean motion in excess of 16 when they decayed.
Ray Hoad
WA5QGD
AMSAT-NA Orbital Elements Manager
From: Robert Bruninga [mailto:bruninga@usna.edu] Sent: Wednesday, December 1, 2021 14:48 To: amsat bb amsat-bb@amsat.org Cc: Robert Bruninga bruninga@usna.edu Subject: [AMSAT-BB] APRS satellite Lifetimes?
Joe, KM1P reminded us of the decay of NO-84 soon.
It woiuld be nice to get an assessment of the remaining lifetimes of the
remaining APRS satellites listed on http://aprs.org/sats.html
Since I retired (and health issues),, I wont be building any replacements
and have not been paying attention.
Joe wanna take a crack at it?
Bob
On Wed, Dec 1, 2021 at 11:05 AM Joseph B. Fitzgerald wrote:
There is a non Russian object threatening NO-84, specifically the earth's
atmosphere. Mean motion is now dangerously close to 16! Time for a Chicken Little contest?
de KM1P Joe
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participants (7)
-
Burns Fisher -
Joe -
Larry Fields -
Nico Janssen -
Pedro Converso -
ray.hoad＠mypbmail.com -
Robert Bruninga