KickSat-2 Re-entry predictions

[Jon]

Hello all,

Some of this group may remember me because I've made re-entry predictions for KickSat in this group.

There are enough published TLEs to start making predictions for KickSat-2 re-entry.

Warning! These predictions are made while Sprites are inside KickSat-2, strongly decreasing satellite's area/mass relation (sq meter/Kg). It's expected that when Sprites are released the KickSat-2's re-entry will be nearer on time.

Current predictions, using two methods:

Prediction made: 25-02-2019 @ 12:00 UTC

SatEvo/SatAna: 2019 Apr- 27

GMAT: 2019 May- 01

Jon.

[Zac Manchester]

Hi Jon,

Yes, I do indeed remember you! I remember that last time you wound up having better predictions than JSPOC. Appreciate having you here.

Best,

Zac 

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[Jon]

Thanks Zac. Indeed lot of the visual satellite tracking community has enough software and knowledge to calculate this kind of things with pretty good accuracy. Will invite other people to participate in this group.

Forgot to mention that re-entry predictions accuracy is about +-three weeks right now.

I will be refreshing predictions once a week more or less in this primary part of the mission. If I have enough time in the last part of the mission will refresh predictions once a day or several times per day.

Jon.

[Janos Tolgyesi]

Jon,
I rerun the SatEvo with the latest tle, with 2 different solar flux index. The first run used the default value, it is 150, indicating a relatively high sunspot activity. The prediction based on this parameter concluded april 30:
Elset       Obj       #         Epoch          Decay        (Date)
     1     18092G    44046   19056.370422   19120.631144  (2019 April 30)
     Decays after   64.2607 days on date = 19120.6311 (2019 April 30)

But the Sun activity now is low, on the www.spaceweather.com actually the value is 71, and seems, the trend dont change dramatically. More data is here:
https://services.swpc.noaa.gov/images/solar-cycle-10-cm-radio-flux.gif
The run, based on this F value shows this prediction:
 Elset       Obj       #         Epoch          Decay        (Date)
     1     18092G    44046   19056.370422   19109.188921  (2019 April 19)
    Decays after   52.8185 days on date = 19109.1889 (2019 April 19)

Maybe the real event will happen between the two date.

The last predicted orbit will 269 x 260 km. The recent orbit is 301 x 288 km
This calculation dont take account of the effect, when the sprites will be deployed, and the mass of Kicksat2 reduced.
Another interesting question would be about the sprite's decay process.
t.janos

[Jon]

Hello,

Janos, you are right. I've made a mistake while scripting GMAT and thereby entered incorrect solar flux in the rest of softwares.

Current revised decay prediction for Kicksat-2, made 04-03-2019 at 19:30 UTC:

-SatEvo/SatAna: 2019 Apr. 9 +- 3 weeks.

-GMAT: 2019 Apr. 10 +- 3 weeks.

These predictions are made while Sprites are inside KickSat-2, so when Sprites are released the area/mass relation will be much lower, making KickSat-2 re-enter in a much nearer date.

Modeling a scenario for Sprites will be much more difficult.

Jon.

[Janos Tolgyesi]

Jon,
I think, the more interesting phenomenon would be the reentry of the sprites. It will be unique, and first case in the history of space research, when we can follow such a small objects, which has the chance to receive at least some weak signal from them. It offers a chance to know were are they, when falling into the more dense atmosphere. I have a feeling, they produce unknown behavior because they small weight and relative big shapes. Maybe in the upper atmosphere they start to produce some types of flaoting moveing, or flights similar as the falling leaves in autumn time. It seems, they can stabilizing the tumbling, and begin a gliding behaviour. This behaviour maybe extend they last section of their flight.
But we didnot prepare ourself to study effective way this situation, because for this we need a world-wide follower network with good ground stations.
I remember to our 1U cubesat, Masat-1, it was in very good condition through its life since the last minutes, and we get the last data from South_America. Ofcourse we lost the contact with it signiphicantly earlier from here, Europe.

By the way, our small pico-balloon team find and study a special floating mode of similarly small objects. They use 5 small balloon to lift on the 18 gramm payload. The balloons have different colours, one, or two usually black. When this train arrive enough high, the first balloon will burst, and the others decrease the altitude, start to flaoting. We have pictures about the landing trains, it was clear, the first balloon was black, which produce the burst.
t.janos
att: launch5ballons.jpg landinghg8lxl.jpg

[TG]

Hi everyone 

I was wondering if anyone has any updates to share. 

Cheers 

Terry

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<launch5ballons.jpg>

<landinghg8lxl.jpg>

[Janos Tolgyesi]

Kicksat-2 decay - update
Based on the recent TLE and the actual Sun radio flux, which is 71 sfu, the decay prediction is as follow:
-------------------------
Orbital evolution for object 18092G 
Decays after   28.5244 days on date = 19101.0528 (2019 April 11)
  10.8 cm flux = 71.000000
The recent TLE:
KICKSAT-2                                        285 x 270 km
1 44046U 18092G   19072.52831502  .00222806  22817-4  44849-3 0 99998
2 44046  51.6357 108.7750 0011144  58.4964 301.6122 15.98780996  4463

The last 2 orbit will be:

KICKSAT-2                                        148 x 147 km
1 44046U 18092G   19100.95813673  .25140158  65395+0  53625-3 0 99997
2 44046  51.6217 314.8609 0001180 173.3516 186.6500 16.46907209  9042
KICKSAT-2                                        137 x 135 km
1 44046U 18092G   19101.01874239  .57385779  61032+1  53369-3 0 99995
2 44046  51.6202 314.5139 0000965 173.6107 186.3905 16.51338130  9054

t.janos

[Jon]

Hello all,

Janos, T G, Zac, rest of members of the group. I intend to post my weekly decay predictions tomorrow at european morning, when I have a bit of free time to make a good analysis. Anyway, preliminary propagations are more stable now, with decay set on second week of April.

Jon.

[Zac Manchester]

Great - thanks Jon!

-Zac

[Jon]

Hello all,

Sorry for the delay in this week's decay predictions.

Solar flux decreased in the last days. This is not good, as solar flux does not compress so much the atmosphere, resulting in more drag for the satellite.

Both methods now points to an earlier decay of the satellite:

SatEvo/SatAna: 2019 Apr. 7 (+- 2 weeks).

GMAT: 2019 Apr- 9 (+- 2 weeks).

I intend to make more reports per week, probably one to several per day when decay date is near.

Janos: Most probably we will not have TLEs for Sprites, so modeling a decay will be unlikely. Remember that those pieces will travel at 7.8 Km/s, so when they hit the mesosphere (~80 Km) they will break, and then they will burn up like any other satellite. The time of passing from 150 Km to 80Km (where the hard part of the decay starts) is several minutes to hours.

Jon.

[Zac Manchester]

Thanks for the update Jon.

-Zac

--

[Alexei Colin]

Hi Jon, by this:

On Thu, Mar 14, 2019 at 05:16:23AM -0700, Jon wrote:
> time of passing from 150 Km to 80Km
> (where the hard part of the decay starts) is several minutes to hours.

Do you mean that sprites will remain in orbit only for at most hours
after release? I was expecting several days. Could you please explain
more what to expect of the sprite lifetime? Thank you.

-a

[Zac Manchester]

We expect Sprite lifetime to be 2~3 days.

-Zac

[Jon]

Re: Alexei, Zac;

Right now KickSat-2 is on a 268 x 282 Km orbit.

I am sure Zac and his team calculated a good orbital height value to deploy Sprites. ;)

Such a tiny spacecrafts on a 150Km cicular orbit will remain some hours (a day or so) in orbit.

Things changes on 200 or 220 Km circular orbit, where a few gram and 3.5x3.5 cm object can survive 2-3 days, according to GMAT propagations.

Jon.

[Jon]

In the attached file you can see a propagation of the last days of KickSat-2.

This graphic is spacecraft altitude (in Kms.) vs days.

At 250 Km mean altitude KickSat-2 will last ~9 days. At 200 Km mean altitude KickSat-2 will last ~1.6 days, and at 150Km mean altitude will last about 6 orbits (less than half a day).

Now imagine a much smaller spacecraft with few grams... ;)

Jon.

[Janos Tolgyesi]

Jon,
thank you for your clarifications and details.

It seems, we can imagine to this small pieces of objects, as small meteorits, when they  reach the lower atmosphere.

t.janos

[Jon]

Hello all,

Solar flux still low. NOAA expects higher values starting Mar. 29. Re-entry predictions were made taking account of that.

Real flux values of next days will be important to improve the accuracy.

I think is good to remember to readers that those predictions are made taking account that Sprites are inside KickSat-2. Once Sprites are released re-entry of KickSat-2 will be pretty faster.

Here are updated re-entry predictions for KickSat-2, using two methods:

SatEvo/SatAna: 2019 Apr. 5 (+- 11 days).

GMAT: 2019 Apr. 7 (+- 11 days).

I intend to make another run this week.

This graphic is derived using SatEvo/SatAna's output. With current data I see 2019 Apr. 5 a bit early for decay, but still depending on next day's solar flux.

Jon.

[Jon]

Hello all,

Congratulations to all KickSat-2 team for succesfull command transmission despite the antenna problem.

Now, as said before, KickSat-2's mass is much lower, so probably re-entry will be nearer on time. Right now there are no updated TLEs since deployment command was sent, and I expect that first two or three TLEs will not be enough accurate to make a new analysis. I will publish new estimations when is possible, probably in about 24-48 hours.

Jon.

[Janos Tolgyesi]

Jon,
What do you think, how we can estimate the orbits of Sprites? In the next some days they will follow the same orbit as the Kicksat2, but later they will diverge slightly. And how can we imagine the last orbits and the decay? Can we have some choices to see something artificial meteor shower, from the 100-th small pieces of objects, fliyng in more or less in the same swarm? Ofcourse in good weather and visibility conditions on proper point of observation.
t.janos

[Jon]

Re:Janos

As you said, in this first day after deployment all Sprites will be near KickSat-2, but because of different drag due to different attitudes and the deploy mechanism delta-v, the small satellites will be separated each other, probably faster than other cases with more mass, so after some days the only successfull method to decode Sprites will be a plane search scan.

I don't mind to explain the plane scan method, or provide some data, so anyone can ask in this thread some basic concepts and methods to search.

Sadly I don't think we'll se any Sprite decay. First, most of the decays occurs over ocean, unpopulated areas, or overcasted areas. Second, because I can't remember any 1U or smaller cubesat re-entry sightning, and third, most likely Sprites will re-enter with some minute to hours of time diffence.

Jon.

[S marie Johnson]

Wonderful!   🛰

--

[Jon]

Hello all,

There are 4 TLEs published for KickSat-2 since Sprites deployment. Small orbit changes were observed, that probably comes from Sprite deployment, but orbit changes are not big enough to confirm that these orbit changes were made because a deploy.

Drag values are quickly increasing, but still not clearly visible an increase after deploy.

These estimations are much less accurate than previous ones, so handle them with caution!

SatEvo/SatAna: 2019 Apr. 1 (+- 7 days).

GMAT: 2019 Apr. 3 (+- 7 days)

I will update those estimations when a better accuracy is available.

Jon.

[Janos Tolgyesi]

Another Kicksat-2 decay prediction:
https://twitter.com/Schillrich/status/1110051659122688000
https://pbs.twimg.com/media/D2ex666XgAArnua.png:large

Running satevo with the recent TLE and 10.7 cm solar flux value 75,  the result date is apr 4.
Jon, what is your calculation?
Maybe the sprites will finished earlier.
t.janos

[S marie Johnson]

Thanks for the update🚀

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[Jon]

Hello all,

I am sorry for not providing updates on those three days, I was out of home with no computers at hand. Tomorrow at european morning will publish my revised update.

I see interesting what published the twitter user Schillrich, so I will re-post it here if he allows me. Also will add USPACECOM estimations when available.

Jon.

[Jon]

Hello all,

Here are updated decay predictions for KickSat-2:

SatEvo/SatAna: 2019 Apr. 2 @ 20h (+- 3 days).

GMAT: 2019 Apr. 3 @ 22h (+- 3 days).

As you can see there are still 26 hours of difference between two analysis. I suspect that right now SatEvo/SatAna one is more accurate than GMAT. Next updates will confirm this.

Other predictions:

USPACECOM released an update in 2019 Apr. 20, decay prediction was 2019 Apr. 9. That prediction is not accurate, as was issued 6 days ago. They are updating every 7 days, so is likely that tomorrow we will have a more accurate one.

Aerospace.org did not issued predictions yet.

Joseph Remis did not issued predictions yet.

Jon.

[Jon]

Hello all,

Here are updated re-entry estimations for KickSat-2:

SatEvo/SatAna: 2019 Apr. 2 @ 13h (+-3 days).

GMAT: 2019 Apr. 2 @ 22h (+-3 days).

As you can see I've adjusted some parameters in GMAT to match the new scenario after Sprites deployment. Now results are much closer to SatAna/SatEvo.

I've tried to modelate a Sprite lifetime since deployment till re-entry. This was made using Cees Bassa's twitter post and Libre Space page of Sprite receiving time vs the position of KickSat-2 on propagated, modified orbit since deployment. Preliminary results indicates that Sprites survived to nearly 3.5 days before re-entry. However there is some uncertainty on that, as I did not find enough data to compute a better lifetime.

Here are some TLEs that models how fast the descent was, that maybe can be usefull for future missions (we wish they will). Propagation was made using SatEvo/SatAna:

SPRITES                                                  274 x 261 km
1 99999U 18092ZZ  19078.14788991  .01749775  15141-2  28532-2 0 90005
2 99999  51.6336  78.7944 0010063  83.7724 276.3422 16.02436059    03
SPRITES                                                  274 x 261 km
1 99999U 18092ZZ  19078.21024727  .01778540  15629-2  28627-2 0 90001
2 99999  51.6336  78.4604 0009983  84.0216 276.0921 16.02656065    15
SPRITES                                                  273 x 260 km
1 99999U 18092ZZ  19078.27259600  .01808322  16158-2  28723-2 0 90004
2 99999  51.6335  78.1264 0009902  84.2709 275.8420 16.02879690    26
SPRITES                                                  272 x 259 km
1 99999U 18092ZZ  19078.33493594  .01839163  16810-2  28821-2 0 90004
2 99999  51.6334  77.7923 0009819  84.5202 275.5918 16.03107063    39
SPRITES                                                  272 x 259 km
1 99999U 18092ZZ  19078.39726696  .01871115  17401-2  28921-2 0 90003
2 99999  51.6333  77.4581 0009737  84.7696 275.3415 16.03338317    42
SPRITES                                                  271 x 258 km
1 99999U 18092ZZ  19078.45958890  .01904240  18025-2  29022-2 0 90005
2 99999  51.6333  77.1238 0009653  85.0190 275.0912 16.03573591    53
SPRITES                                                  270 x 258 km
1 99999U 18092ZZ  19078.52190161  .01938603  18683-2  29125-2 0 90006
2 99999  51.6332  76.7895 0009568  85.2684 274.8408 16.03813036    60
SPRITES                                                  270 x 257 km
1 99999U 18092ZZ  19078.58420491  .01974283  19498-2  29229-2 0 90008
2 99999  51.6331  76.4551 0009483  85.5180 274.5904 16.04056808    71
SPRITES                                                  269 x 256 km
1 99999U 18092ZZ  19078.64649866  .02011355  20241-2  29335-2 0 90003
2 99999  51.6330  76.1207 0009396  85.7675 274.3398 16.04305073    86
SPRITES                                                  268 x 256 km
1 99999U 18092ZZ  19078.70878266  .02049901  21028-2  29442-2 0 90009
2 99999  51.6330  75.7861 0009309  86.0171 274.0893 16.04558009    93
SPRITES                                                  267 x 255 km
1 99999U 18092ZZ  19078.77105674  .02090012  21862-2  29552-2 0 90009
2 99999  51.6329  75.4516 0009220  86.2668 273.8386 16.04815801   102
SPRITES                                                  267 x 254 km
1 99999U 18092ZZ  19078.83332070  .02131787  22901-2  29663-2 0 90001
2 99999  51.6328  75.1169 0009131  86.5165 273.5879 16.05078649   115
SPRITES                                                  266 x 254 km
1 99999U 18092ZZ  19078.89557436  .02175342  23852-2  29776-2 0 90008
2 99999  51.6327  74.7821 0009041  86.7663 273.3371 16.05346765   122
SPRITES                                                  265 x 253 km
1 99999U 18092ZZ  19078.95781750  .02220785  24865-2  29891-2 0 90008
2 99999  51.6327  74.4473 0008949  87.0162 273.0862 16.05620373   139
SPRITES                                                  264 x 252 km
1 99999U 18092ZZ  19079.02004991  .02268243  25945-2  30008-2 0 90005
2 99999  51.6326  74.1124 0008856  87.2661 272.8353 16.05899714   141
SPRITES                                                  263 x 252 km
1 99999U 18092ZZ  19079.08227137  .02317855  27098-2  30126-2 0 90006
2 99999  51.6325  73.7775 0008762  87.5160 272.5843 16.06185045   158
SPRITES                                                  262 x 251 km
1 99999U 18092ZZ  19079.14448165  .02369785  28545-2  30247-2 0 90000
2 99999  51.6324  73.4424 0008667  87.7661 272.3332 16.06476640   163
SPRITES                                                  261 x 250 km
1 99999U 18092ZZ  19079.20668049  .02424194  29881-2  30371-2 0 90000
2 99999  51.6323  73.1073 0008571  88.0162 272.0820 16.06774793   173
SPRITES                                                  261 x 249 km
1 99999U 18092ZZ  19079.26886765  .02481262  31315-2  30496-2 0 90005
2 99999  51.6322  72.7720 0008473  88.2663 271.8307 16.07079820   183
SPRITES                                                  260 x 249 km
1 99999U 18092ZZ  19079.33104285  .02535285  28035-2  30553-2 0 90007
2 99999  51.6321  72.4367 0008374  88.5165 271.5794 16.07391814   194
SPRITES                                                  259 x 248 km
1 99999U 18092ZZ  19079.39320585  .02588952  29577-2  30577-2 0 90003
2 99999  51.6320  72.1013 0008274  88.7668 271.3280 16.07710325   209
SPRITES                                                  258 x 247 km
1 99999U 18092ZZ  19079.45535639  .02645266  31008-2  30602-2 0 90001
2 99999  51.6319  71.7658 0008173  89.0172 271.0765 16.08035607   219
SPRITES                                                  257 x 246 km
1 99999U 18092ZZ  19079.51749421  .02704427  32551-2  30628-2 0 90001
2 99999  51.6318  71.4303 0008071  89.2676 270.8249 16.08367994   222
SPRITES                                                  256 x 245 km
1 99999U 18092ZZ  19079.57961902  .02766665  34217-2  30656-2 0 90001
2 99999  51.6317  71.0946 0007968  89.5181 270.5732 16.08707851   233
SPRITES                                                  255 x 244 km
1 99999U 18092ZZ  19079.64173055  .02832159  35721-2  30684-2 0 90007
2 99999  51.6316  70.7588 0007863  89.7687 270.3214 16.09055571   247
SPRITES                                                  254 x 243 km
1 99999U 18092ZZ  19079.70382849  .02897988  36197-2  30680-2 0 90002
2 99999  51.6315  70.4229 0007758  90.0193 270.0696 16.09411368   257
SPRITES                                                  253 x 242 km
1 99999U 18092ZZ  19079.76591253  .02966507  37851-2  30668-2 0 90007
2 99999  51.6314  70.0870 0007651  90.2701 269.8176 16.09775424   269
SPRITES                                                  252 x 242 km
1 99999U 18092ZZ  19079.82798234  .03038949  40046-2  30657-2 0 90001
2 99999  51.6313  69.7509 0007542  90.5209 269.5656 16.10148138   276
SPRITES                                                  250 x 241 km
1 99999U 18092ZZ  19079.89003760  .03115794  42448-2  30649-2 0 90004
2 99999  51.6312  69.4147 0007432  90.7717 269.3134 16.10530024   283
SPRITES                                                  249 x 240 km
1 99999U 18092ZZ  19079.95207794  .03200130  53495-2  30670-2 0 90001
2 99999  51.6311  69.0784 0007321  91.0227 269.0612 16.10921679   291
SPRITES                                                  248 x 239 km
1 99999U 18092ZZ  19080.01410297  .03303615  57787-2  30820-2 0 90001
2 99999  51.6309  68.7420 0007208  91.2738 268.8088 16.11325002   309
SPRITES                                                  247 x 237 km
1 99999U 18092ZZ  19080.07611220  .03414546  61900-2  30975-2 0 90005
2 99999  51.6308  68.4055 0007092  91.5249 268.5563 16.11741509   310
SPRITES                                                  246 x 236 km
1 99999U 18092ZZ  19080.13810511  .03533759  66479-2  31135-2 0 90009
2 99999  51.6307  68.0689 0006974  91.7761 268.3037 16.12172163   327
SPRITES                                                  244 x 235 km
1 99999U 18092ZZ  19080.20008116  .03662237  71598-2  31300-2 0 90003
2 99999  51.6306  67.7321 0006853  92.0275 268.0510 16.12618039   336
SPRITES                                                  243 x 234 km
1 99999U 18092ZZ  19080.26203975  .03801127  77346-2  31472-2 0 90009
2 99999  51.6304  67.3953 0006729  92.2789 267.7982 16.13080345   349
SPRITES                                                  242 x 233 km
1 99999U 18092ZZ  19080.32398021  .03951819  84993-2  31650-2 0 90001
2 99999  51.6303  67.0582 0006602  92.5304 267.5452 16.13560438   356
SPRITES                                                  240 x 232 km
1 99999U 18092ZZ  19080.38590186  .04115903  92510-2  31836-2 0 90000
2 99999  51.6301  66.7211 0006472  92.7820 267.2920 16.14059857   366
SPRITES                                                  239 x 230 km
1 99999U 18092ZZ  19080.44780393  .04295259  10109-1  32029-2 0 90009
2 99999  51.6300  66.3838 0006338  93.0338 267.0387 16.14580354   372
SPRITES                                                  237 x 229 km
1 99999U 18092ZZ  19080.50968559  .04492172  11096-1  32230-2 0 90001
2 99999  51.6298  66.0464 0006201  93.2856 266.7853 16.15123938   383
SPRITES                                                  235 x 227 km
1 99999U 18092ZZ  19080.57154591  .04709412  12238-1  32440-2 0 90001
2 99999  51.6297  65.7088 0006059  93.5376 266.5317 16.15692924   391
SPRITES                                                  234 x 226 km
1 99999U 18092ZZ  19080.63338390  .04949856  12294-1  32655-2 0 90007
2 99999  51.6294  65.3710 0005913  93.7897 266.2779 16.16290003   408
SPRITES                                                  232 x 224 km
1 99999U 18092ZZ  19080.69519845  .05188824  13670-1  32700-2 0 90000
2 99999  51.6293  65.0331 0005762  94.0419 266.0239 16.16916454   414
SPRITES                                                  230 x 223 km
1 99999U 18092ZZ  19080.75698844  .05456099  15302-1  32755-2 0 90000
2 99999  51.6291  64.6949 0005607  94.2943 265.7698 16.17573882   425
SPRITES                                                  228 x 221 km
1 99999U 18092ZZ  19080.81875264  .05754677  16639-1  32806-2 0 90004
2 99999  51.6289  64.3566 0005448  94.5468 265.5154 16.18266039   432
SPRITES                                                  226 x 219 km
1 99999U 18092ZZ  19080.88048967  .06103564  21218-1  32922-2 0 90005
2 99999  51.6287  64.0181 0005283  94.7995 265.2608 16.18997043   442
SPRITES                                                  224 x 217 km
1 99999U 18092ZZ  19080.94219791  .06528698  24450-1  33173-2 0 90006
2 99999  51.6285  63.6794 0005112  95.0523 265.0060 16.19775923   450
SPRITES                                                  221 x 215 km
1 99999U 18092ZZ  19081.00387540  .07023896  29285-1  33444-2 0 90005
2 99999  51.6282  63.3405 0004933  95.3053 264.7510 16.20611015   464
SPRITES                                                  219 x 212 km
1 99999U 18092ZZ  19081.06551984  .07608556  34712-1  33737-2 0 90004
2 99999  51.6279  63.0013 0004746  95.5585 264.4956 16.21511982   471
SPRITES                                                  216 x 210 km
1 99999U 18092ZZ  19081.12712855  .08310029  41859-1  34055-2 0 90007
2 99999  51.6276  62.6618 0004547  95.8119 264.2399 16.22491312   484
SPRITES                                                  213 x 207 km
1 99999U 18092ZZ  19081.18869827  .09168543  51551-1  34404-2 0 90006
2 99999  51.6273  62.3221 0004335  96.0655 263.9839 16.23565557   491
SPRITES                                                  209 x 204 km
1 99999U 18092ZZ  19081.25022506  .10245593  65188-1  34788-2 0 90008
2 99999  51.6270  61.9820 0004107  96.3193 263.7274 16.24757362   506
SPRITES                                                  206 x 201 km
1 99999U 18092ZZ  19081.31170394  .11640349  85294-1  35217-2 0 90001
2 99999  51.6267  61.6416 0003860  96.5735 263.4705 16.26098941   519
SPRITES                                                  201 x 197 km
1 99999U 18092ZZ  19081.37312845  .13553079  12586+0  35770-2 0 90007
2 99999  51.6261  61.3008 0003591  96.8279 263.2130 16.27640035   523
SPRITES                                                  196 x 192 km
1 99999U 18092ZZ  19081.43448977  .16210523  17184+0  36205-2 0 90000
2 99999  51.6256  60.9595 0003290  97.0827 262.9547 16.29458791   538
SPRITES                                                  190 x 186 km
1 99999U 18092ZZ  19081.49577562  .20153140  27911+0  36410-2 0 90002
2 99999  51.6250  60.6177 0002945  97.3379 262.6956 16.31667601   543
SPRITES                                                  182 x 179 km
1 99999U 18092ZZ  19081.55696749  .27391893  57516+0  37008-2 0 90002
2 99999  51.6242  60.2751 0002529  97.5937 262.4350 16.34520319   552
SPRITES                                                  171 x 168 km
1 99999U 18092ZZ  19081.61803114  .44032042  15619+1  37392-2 0 90007
2 99999  51.6231  59.9316 0001996  97.8502 262.1725 16.38689787   563
SPRITES                                                  144 x 143 km
1 99999U 18092ZZ  19081.67887115 1.98148795  36701+2  30847-2 0 90003
2 99999  51.6213  59.5864 0001108  98.1080 261.9045 16.48481144   578

This gives the following altitude graphic, compared to KickSat-2 (Where black and green lines are Sprites apogee and perigee and red and blue KickSat-2's apogee and perigee, with real data and propagated till decay:

Jon.

[Zac Manchester]

Cool - thanks Jon!

On Mar 27, 2019, 5:55 AM -0700, Jon <jonm...@gmail.com>, wrote:

Hello all,

Here are updated re-entry estimations for KickSat-2:

SatEvo/SatAna: 2019 Apr. 2 @ 13h (+-3 days).

GMAT: 2019 Apr. 2 @ 22h (+-3 days).

As you can see I've adjusted some parameters in GMAT to match the new scenario after Sprites deployment. Now results are much closer to SatAna/SatEvo.

<Spritesdecay.png>

Jon.

[Jon]

Hello all,

Here are updated KickSat-2 re-entry predictions:

SatEvo/SatAna: 2019 Apr. 2 @ 19h (+- 2.5 days).

GMAT: 2019 Apr. 2 @ 14h (+-2.5 days).

Now that re-entry is only ~5 days apart we can start delimiting re-entry areas. As you can se in the following ground track plot, this is the trajectory of KickSat-2 for the next days till re-entry. The areas along the ground track line are the only sites that KickSat-2 can re-enter.

Please keep in mind that most part of the ground track of KickSat-2 is over water, and that lot of ground sites are unpopulated, in daytime or overcast. A few kilogram mass satellite is very difficult to see re-enter, even if all the above conditions are good.

Jon.

[Jon]

Hello all,

As you can see the re-entry date is nearer than expected in previous days (Apr. 1-2 vs Apr- 2-4). That's probably because the hard-to-model solar flux, that is lower than expected. Here today's estimations:

SatEvo/SatAna: 2019 Apr. 1 @ 22h (+- 2 days).

GMAT: 2019 Apr. 2 @ 11h (+- 2days).

USPACECOM issued a new re-entry prediction today: 2019 Apr. 2 @ 07:00. Their next report will be issued in 72 hours.

Schillrich Twitter user posted new graphics about KicSat-2's descent.

Joseph Remis estimated yesterday KickSat-2's re-entry: 2019 Apr. 3 @ 11h12' (+- 38 hours) on his twitter account

Here the updated ground track plot for re-entry locations:

Jon.

[Zac Manchester]

Thanks for the update Jon!

-Zac

<Auto Generated Inline Image 1.png>

Jon.

[Jon]

Hello all,

Here are updated KickSat-2 re-entry predictions:

SatEvo/SatAna: 2019 Apr. 2 @ 8h 27' UTC (+- 15 hours).

GMAT: 2019 Apr. 2 @ 13h 41' UTC (+- 15 hours).

I am more confident of GMAT analysis in this case, so, and only if there are difficulties to track KickSat-2 on it's high-drag last orbits, here are integrated SatEvo/SatAna TLE format output forced to decay at ~13h 41' UTC. Use them with caution, and each in the correct epoch. Allow some seconds of uncertainty in time and few degrees of uncertainty on track:

KICKSAT 2                                                224 x 213 km
1 44046U 18092G   19089.88708225  .01912996  20080-2  91405-3 0 99995
2 44046  51.6283  15.3304 0008558 192.5358 167.4431 16.20496316  7258
KICKSAT 2                                                223 x 212 km
1 44046U 18092G   19089.94874380  .01950864  20965-2  91494-3 0 99994
2 44046  51.6282  14.9913 0008477 192.7889 167.1896 16.20734551  7268
KICKSAT 2                                                223 x 211 km
1 44046U 18092G   19090.01039619  .01990404  21876-2  91583-3 0 99997
2 44046  51.6282  14.6522 0008394 193.0420 166.9362 16.20977521  7276
KICKSAT 2                                                222 x 211 km
1 44046U 18092G   19090.07203923  .02031725  22849-2  91674-3 0 99999
2 44046  51.6281  14.3130 0008311 193.2952 166.6828 16.21225439  7288
KICKSAT 2                                                221 x 210 km
1 44046U 18092G   19090.13367275  .02074950  23891-2  91764-3 0 99992
2 44046  51.6280  13.9737 0008226 193.5485 166.4294 16.21478527  7298
KICKSAT 2                                                220 x 210 km
1 44046U 18092G   19090.19529654  .02120220  25008-2  91855-3 0 99994
2 44046  51.6280  13.6344 0008140 193.8018 166.1759 16.21737027  7307
KICKSAT 2                                                220 x 209 km
1 44046U 18092G   19090.25691040  .02167686  26208-2  91947-3 0 99992
2 44046  51.6279  13.2950 0008053 194.0551 165.9224 16.22001198  7311
KICKSAT 2                                                219 x 208 km
1 44046U 18092G   19090.31851410  .02217527  27723-2  92039-3 0 99994
2 44046  51.6278  12.9555 0007964 194.3086 165.6689 16.22271319  7320
KICKSAT 2                                                218 x 208 km
1 44046U 18092G   19090.38010741  .02269922  29132-2  92131-3 0 99990
2 44046  51.6277  12.6159 0007874 194.5620 165.4153 16.22547688  7332
KICKSAT 2                                                217 x 207 km
1 44046U 18092G   19090.44169011  .02325077  30654-2  92223-3 0 99999
2 44046  51.6276  12.2763 0007783 194.8156 165.1616 16.22830631  7349
KICKSAT 2                                                216 x 206 km
1 44046U 18092G   19090.50326193  .02383222  32302-2  92316-3 0 99993
2 44046  51.6275  11.9365 0007689 195.0692 164.9079 16.23120497  7359
KICKSAT 2                                                215 x 205 km
1 44046U 18092G   19090.56482261  .02444614  34091-2  92408-3 0 99990
2 44046  51.6275  11.5967 0007595 195.3228 164.6541 16.23417667  7367
KICKSAT 2                                                214 x 205 km
1 44046U 18092G   19090.62637187  .02509541  36038-2  92500-3 0 99993
2 44046  51.6274  11.2568 0007499 195.5766 164.4003 16.23722554  7378
KICKSAT 2                                                214 x 204 km
1 44046U 18092G   19090.68790942  .02576620  37027-2  92531-3 0 99993
2 44046  51.6273  10.9169 0007400 195.8303 164.1465 16.24035541  7386
KICKSAT 2                                                213 x 203 km
1 44046U 18092G   19090.74943493  .02646765  39260-2  92527-3 0 99995
2 44046  51.6272  10.5768 0007301 196.0842 163.8926 16.24356870  7397
KICKSAT 2                                                212 x 202 km
1 44046U 18092G   19090.81094811  .02721302  41708-2  92523-3 0 99991
2 44046  51.6271  10.2366 0007199 196.3381 163.6386 16.24687029  7406
KICKSAT 2                                                211 x 201 km
1 44046U 18092G   19090.87244860  .02800670  44402-2  92517-3 0 99991
2 44046  51.6270   9.8964 0007095 196.5921 163.3846 16.25026580  7419
KICKSAT 2                                                210 x 200 km
1 44046U 18092G   19090.93393604  .02885373  47376-2  92511-3 0 99999
2 44046  51.6269   9.5560 0006990 196.8462 163.1305 16.25376142  7423
KICKSAT 2                                                209 x 200 km
1 44046U 18092G   19090.99541005  .02975989  50670-2  92504-3 0 99991
2 44046  51.6268   9.2156 0006882 197.1004 162.8764 16.25736399  7436
KICKSAT 2                                                208 x 199 km
1 44046U 18092G   19091.05687022  .03072207  53567-2  92467-3 0 99997
2 44046  51.6267   8.8750 0006772 197.3546 162.6222 16.26108069  7447
KICKSAT 2                                                206 x 198 km
1 44046U 18092G   19091.11831610  .03180964  62417-2  92581-3 0 99999
2 44046  51.6265   8.5343 0006659 197.6089 162.3680 16.26492147  7458
KICKSAT 2                                                205 x 197 km
1 44046U 18092G   19091.17974720  .03300079  67445-2  92739-3 0 99997
2 44046  51.6264   8.1936 0006544 197.8633 162.1137 16.26890188  7464
KICKSAT 2                                                204 x 196 km
1 44046U 18092G   19091.24116298  .03428853  70323-2  92885-3 0 99995
2 44046  51.6263   7.8527 0006426 198.1178 161.8593 16.27303361  7478
KICKSAT 2                                                203 x 195 km
1 44046U 18092G   19091.30256286  .03558982  73328-2  92774-3 0 99996
2 44046  51.6262   7.5117 0006306 198.3724 161.6048 16.27732328  7488
KICKSAT 2                                                202 x 193 km
1 44046U 18092G   19091.36394624  .03700135  79862-2  92644-3 0 99995
2 44046  51.6261   7.1706 0006182 198.6270 161.3503 16.28177789  7497
KICKSAT 2                                                200 x 192 km
1 44046U 18092G   19091.42531248  .03854473  87351-2  92508-3 0 99993
2 44046  51.6259   6.8293 0006054 198.8818 161.0957 16.28641242  7501
KICKSAT 2                                                199 x 191 km
1 44046U 18092G   19091.48666089  .04024021  95995-2  92364-3 0 99993
2 44046  51.6258   6.4879 0005922 199.1367 160.8411 16.29124409  7517
KICKSAT 2                                                197 x 190 km
1 44046U 18092G   19091.54799068  .04221763  11417-1  92439-3 0 99995
2 44046  51.6256   6.1464 0005786 199.3917 160.5863 16.29629906  7524
KICKSAT 2                                                196 x 188 km
1 44046U 18092G   19091.60930096  .04442220  12739-1  92512-3 0 99993
2 44046  51.6255   5.8047 0005645 199.6467 160.3315 16.30160847  7530
KICKSAT 2                                                194 x 187 km
1 44046U 18092G   19091.67059075  .04689490  14312-1  92578-3 0 99992
2 44046  51.6253   5.4629 0005498 199.9019 160.0766 16.30720226  7543
KICKSAT 2                                                193 x 186 km
1 44046U 18092G   19091.73185890  .04968960  16208-1  92637-3 0 99998
2 44046  51.6251   5.1209 0005346 200.1573 159.8216 16.31311615  7550
KICKSAT 2                                                191 x 184 km
1 44046U 18092G   19091.79310417  .05287593  18521-1  92685-3 0 99999
2 44046  51.6250   4.7787 0005187 200.4127 159.5665 16.31939332  7564
KICKSAT 2                                                189 x 182 km
1 44046U 18092G   19091.85432511  .05654556  21387-1  92719-3 0 99995
2 44046  51.6248   4.4364 0005021 200.6683 159.3114 16.32608666  7577
KICKSAT 2                                                187 x 181 km
1 44046U 18092G   19091.91552006  .06082175  25001-1  92734-3 0 99991
2 44046  51.6246   4.0939 0004847 200.9241 159.0561 16.33326198  7589
KICKSAT 2                                                185 x 179 km
1 44046U 18092G   19091.97668708  .06545984  23347-1  92151-3 0 99990
2 44046  51.6244   3.7511 0004663 201.1800 158.8007 16.34099316  7592
KICKSAT 2                                                182 x 176 km
1 44046U 18092G   19092.03782412  .07020899  28742-1  90579-3 0 99997
2 44046  51.6241   3.4081 0004471 201.4361 158.5452 16.34927892  7602
KICKSAT 2                                                180 x 174 km
1 44046U 18092G   19092.09892901  .07633784  41183-1  89463-3 0 99995
2 44046  51.6238   3.0649 0004270 201.6923 158.2896 16.35820685  7610
KICKSAT 2                                                177 x 172 km
1 44046U 18092G   19092.15999897  .08473306  52022-1  89114-3 0 99994
2 44046  51.6235   2.7214 0004058 201.9488 158.0338 16.36802318  7628
KICKSAT 2                                                174 x 169 km
1 44046U 18092G   19092.22103023  .09549060  67596-1  88681-3 0 99992
2 44046  51.6232   2.3777 0003834 202.2055 157.7779 16.37899293  7635
KICKSAT 2                                                170 x 166 km
1 44046U 18092G   19092.28201792  .10993965  92795-1  88216-3 0 99992
2 44046  51.6229   2.0336 0003588 202.4624 157.5218 16.39147385  7646
KICKSAT 2                                                166 x 162 km
1 44046U 18092G   19092.34295552  .13090722  14061+0  87955-3 0 99995
2 44046  51.6225   1.6891 0003309 202.7197 157.2657 16.40605701  7650
KICKSAT 2                                                161 x 158 km
1 44046U 18092G   19092.40383346  .16425184  23189+0  87917-3 0 99997
2 44046  51.6220   1.3441 0002981 202.9773 157.0094 16.42385153  7662
KICKSAT 2                                                155 x 152 km
1 44046U 18092G   19092.46463637  .22569394  46528+0  75663-3 0 99991
2 44046  51.6214   0.9986 0002576 203.2353 156.7531 16.44711547  7677
KICKSAT 2                                                145 x 143 km
1 44046U 18092G   19092.52533488  .38594535  14813+1  62204-3 0 99992
2 44046  51.6206   0.6523 0002002 203.4939 156.4969 16.48230717  76804

Here the decay site ground track plot. In tomorrow's analysis I'll start to post the few-orbit refined re-entry groung track plot:

USPACECOM published a new decay TIP message in Mar. 29. New estimation is Apr. 1 @ 21h 18' UTC. Their next report will be in some hours.

After running some simulations forcing some variables to change till illogical values I conclude that this is too early estimate.

Joseph Remis published 14 hours ago in his twitter account his update: 2019 Apr. 2 @ 7h 48' UTC (+- 22 hours).

Jon.

[Jon]

Hello all,

Here are updated decay predictions for KickSat-2:

SatEvo/SatAna: 2019 Apr. 2 @ 11h 44' UTC (+- 12 hours).

GMAT: 2019 Apr. 2 @ 11h 17' UTC (+- 12 hours).

USPACECOM issued a new decay prediction some hours ago: 2019 Apr. 2 @ 8h 51' UTC. This is a much better estimation than the last one and still well inside the error range.

Here are updated TLE integrations for forced decay at 11h 30' UTC (mean of both my re-entry predictions). As I said yesterday, Use them with caution, and each in the correct epoch. Allow some seconds of uncertainty in time and few degrees of uncertainty on track:

KICKSAT 2                                                220 x 208 km
1 44046U 18092G   19090.25690259  .02235069  27749-2  94296-3 0 99995
2 44046  51.6302  13.2892 0008431 196.7176 163.2547 16.22058563  7312

KICKSAT 2                                                219 x 208 km

1 44046U 18092G   19090.31850397  .02287531  29203-2  94368-3 0 99991
2 44046  51.6301  12.9497 0008336 196.9710 163.0011 16.22337134  7327
KICKSAT 2                                                218 x 207 km
1 44046U 18092G   19090.38009464  .02342757  30721-2  94441-3 0 99990
2 44046  51.6300  12.6101 0008240 197.2244 162.7476 16.22622287  7333
KICKSAT 2                                                217 x 206 km
1 44046U 18092G   19090.44167435  .02400958  32364-2  94513-3 0 99993
2 44046  51.6300  12.2705 0008142 197.4779 162.4940 16.22914371  7347

KICKSAT 2                                                216 x 206 km

1 44046U 18092G   19090.50324283  .02462391  34146-2  94585-3 0 99994
2 44046  51.6299  11.9308 0008042 197.7315 162.2404 16.23213765  7351

KICKSAT 2                                                215 x 205 km

1 44046U 18092G   19090.56479980  .02527338  36085-2  94655-3 0 99990
2 44046  51.6298  11.5909 0007940 197.9851 161.9868 16.23520880  7366

KICKSAT 2                                                214 x 204 km

1 44046U 18092G   19090.62634497  .02595531  36728-2  94702-3 0 99990
2 44046  51.6297  11.2510 0007837 198.2388 161.7331 16.23836154  7372

KICKSAT 2                                                213 x 203 km

1 44046U 18092G   19090.68787802  .02665676  39302-2  94672-3 0 99990
2 44046  51.6296  10.9110 0007732 198.4926 161.4793 16.24159850  7389

KICKSAT 2                                                212 x 202 km

1 44046U 18092G   19090.74939864  .02740188  41737-2  94640-3 0 99996
2 44046  51.6295  10.5709 0007625 198.7464 161.2255 16.24492375  7393
KICKSAT 2                                                211 x 202 km
1 44046U 18092G   19090.81090648  .02819496  44416-2  94607-3 0 99991
2 44046  51.6294  10.2308 0007516 199.0003 160.9716 16.24834287  7408
KICKSAT 2                                                210 x 201 km
1 44046U 18092G   19090.87240118  .02904096  47370-2  94571-3 0 99999
2 44046  51.6293   9.8905 0007404 199.2543 160.7177 16.25186200  7417

KICKSAT 2                                                209 x 200 km

1 44046U 18092G   19090.93388235  .02994556  50641-2  94534-3 0 99993
2 44046  51.6292   9.5501 0007291 199.5083 160.4637 16.25548792  7428

KICKSAT 2                                                208 x 199 km

1 44046U 18092G   19090.99534959  .03091012  53513-2  94478-3 0 99999
2 44046  51.6291   9.2096 0007175 199.7625 160.2097 16.25922804  7437
KICKSAT 2                                                207 x 198 km
1 44046U 18092G   19091.05680246  .03193766  57489-2  94393-3 0 99999
2 44046  51.6290   8.8690 0007057 200.0167 159.9556 16.26308945  7448
KICKSAT 2                                                206 x 197 km
1 44046U 18092G   19091.11824048  .03308410  67181-2  94416-3 0 99996
2 44046  51.6288   8.5283 0006935 200.2710 159.7015 16.26708219  7457
KICKSAT 2                                                205 x 196 km
1 44046U 18092G   19091.17966314  .03436778  72795-2  94551-3 0 99991
2 44046  51.6287   8.1875 0006811 200.5254 159.4472 16.27122419  7466
KICKSAT 2                                                204 x 195 km
1 44046U 18092G   19091.24106985  .03568767  72979-2  94483-3 0 99991
2 44046  51.6286   7.8466 0006684 200.7799 159.1929 16.27552627  7474
KICKSAT 2                                                202 x 194 km
1 44046U 18092G   19091.30246001  .03708956  79425-2  94322-3 0 99993
2 44046  51.6285   7.5055 0006554 201.0344 158.9386 16.27999282  7487
KICKSAT 2                                                201 x 193 km
1 44046U 18092G   19091.36383299  .03862115  86807-2  94153-3 0 99992
2 44046  51.6283   7.1643 0006419 201.2891 158.6842 16.28463797  7496
KICKSAT 2                                                200 x 191 km
1 44046U 18092G   19091.42518809  .04036480  10063-1  94119-3 0 99997
2 44046  51.6282   6.8230 0006281 201.5439 158.4297 16.28948122  7505
KICKSAT 2                                                198 x 190 km
1 44046U 18092G   19091.48652452  .04232569  11138-1  94149-3 0 99999
2 44046  51.6281   6.4815 0006138 201.7988 158.1751 16.29455110  7515
KICKSAT 2                                                197 x 189 km
1 44046U 18092G   19091.54784138  .04450822  12632-1  94173-3 0 99994
2 44046  51.6279   6.1399 0005989 202.0538 157.9204 16.29987306  7522
KICKSAT 2                                                195 x 187 km
1 44046U 18092G   19091.60913770  .04695323  14175-1  94188-3 0 99994
2 44046  51.6277   5.7982 0005836 202.3089 157.6657 16.30547640  7533

KICKSAT 2                                                193 x 186 km

1 44046U 18092G   19091.67041236  .04971253  16030-1  94192-3 0 99996
2 44046  51.6276   5.4562 0005676 202.5641 157.4109 16.31139601  7547

KICKSAT 2                                                191 x 184 km

1 44046U 18092G   19091.73166412  .05285317  18289-1  94180-3 0 99992
2 44046  51.6274   5.1141 0005510 202.8195 157.1560 16.31767398  7558
KICKSAT 2                                                190 x 183 km
1 44046U 18092G   19091.79289155  .05646311  21080-1  94150-3 0 99993
2 44046  51.6272   4.7719 0005336 203.0750 156.9010 16.32436173  7561
KICKSAT 2                                                188 x 181 km
1 44046U 18092G   19091.85409301  .06066018  24589-1  94096-3 0 99994
2 44046  51.6270   4.4294 0005153 203.3306 156.6460 16.33152305  7571

KICKSAT 2                                                185 x 179 km

1 44046U 18092G   19091.91526663  .06538650  22941-1  93699-3 0 99996
2 44046  51.6268   4.0867 0004960 203.5865 156.3908 16.33923551  7581
KICKSAT 2                                                183 x 177 km
1 44046U 18092G   19091.97641030  .07002719  27289-1  92016-3 0 99993
2 44046  51.6266   3.7438 0004759 203.8424 156.1355 16.34750689  7595
KICKSAT 2                                                180 x 175 km
1 44046U 18092G   19092.03752190  .07565799  40319-1  90385-3 0 99999
2 44046  51.6262   3.4007 0004548 204.0986 155.8801 16.35639722  7601
KICKSAT 2                                                178 x 172 km
1 44046U 18092G   19092.09859882  .08377833  50370-1  89962-3 0 99999
2 44046  51.6260   3.0573 0004327 204.3550 155.6245 16.36611657  7617
KICKSAT 2                                                175 x 169 km
1 44046U 18092G   19092.15963747  .09411910  65035-1  89445-3 0 99998
2 44046  51.6257   2.7136 0004092 204.6116 155.3689 16.37694814  7621
KICKSAT 2                                                171 x 166 km
1 44046U 18092G   19092.22063317  .10787694  88494-1  88869-3 0 99990
2 44046  51.6253   2.3695 0003837 204.8684 155.1131 16.38922509  7638
KICKSAT 2                                                167 x 163 km
1 44046U 18092G   19092.28157972  .12751445  13232+0  88414-3 0 99996
2 44046  51.6249   2.0251 0003549 205.1256 154.8572 16.40348703  7644
KICKSAT 2                                                162 x 158 km
1 44046U 18092G   19092.34246816  .15826216  21365+0  88203-3 0 99993
2 44046  51.6245   1.6803 0003214 205.3830 154.6012 16.42073391  7655
KICKSAT 2                                                156 x 153 km
1 44046U 18092G   19092.40328438  .21296866  41174+0  78268-3 0 99990
2 44046  51.6239   1.3349 0002803 205.6409 154.3452 16.44293664  7663
KICKSAT 2                                                147 x 144 km
1 44046U 18092G   19092.46400252  .34383495  11760+1  63332-3 0 99995
2 44046  51.6231   0.9888 0002240 205.8994 154.0894 16.47531298  7673

Here is ground track where with 100% of probabilities will re-enter:

And here the three orbits before and after the estimated re entry time, where probabilities are ~50% to re-enter there. Map made using Orbitron:

I will issue a new update at european night.

Jon.

[Jon]

Hello all,

Here the updated re-entry predictions for KickSat-2:

SatEvo/SatAna: 2019 Apr. 2 @ 08h 03' UTC (+- 12 hours).

GMAT: 2019 Apr. 2 @ 11h 12' UTC (+- 12 hours).

I am experimenting some differences between two methods that I assume will be solved for next report.

USPACECOM released a new TIP message with re-entry estimate the 2019 Apr. 2 @ 08h 51' UTC.

Here are updated integrated TLE solutions for forced re-entry at 11h 15' UTC, derived using SatEvo/SatAna. That's because I am more confident with GMAT prediction that SatEvo/SatAna's in this case. As I said yesterday, Use them with caution, and each in the correct epoch. Allow some seconds of uncertainty in time and few degrees of uncertainty on track:

KICKSAT 2                                                219 x 208 km

1 44046U 18092G   19090.25690259  .02270880  28672-2  95340-3 0 99992
2 44046  51.6302  13.2892 0008431 196.7176 163.2547 16.22118825  7310

KICKSAT 2                                                219 x 208 km

1 44046U 18092G   19090.31850160  .02325103  30199-2  95414-3 0 99996
2 44046  51.6301  12.9497 0008334 196.9710 163.0011 16.22401904  7322

KICKSAT 2                                                218 x 207 km

1 44046U 18092G   19090.38008972  .02382233  31797-2  95488-3 0 99992
2 44046  51.6300  12.6101 0008236 197.2244 162.7476 16.22691789  7331

KICKSAT 2                                                217 x 206 km

1 44046U 18092G   19090.44166669  .02442497  33529-2  95561-3 0 99993
2 44046  51.6300  12.2704 0008137 197.4780 162.4940 16.22988847  7341
KICKSAT 2                                                216 x 205 km
1 44046U 18092G   19090.50323225  .02506170  35411-2  95634-3 0 99995
2 44046  51.6299  11.9307 0008035 197.7315 162.2404 16.23293478  7351

KICKSAT 2                                                215 x 205 km

1 44046U 18092G   19090.56478609  .02573557  37461-2  95705-3 0 99997
2 44046  51.6298  11.5908 0007932 197.9852 161.9867 16.23606114  7361

KICKSAT 2                                                214 x 204 km

1 44046U 18092G   19090.62632792  .02643567  38164-2  95724-3 0 99990
2 44046  51.6297  11.2509 0007827 198.2389 161.7330 16.23927185  7374

KICKSAT 2                                                213 x 203 km

1 44046U 18092G   19090.68785741  .02716498  40895-2  95692-3 0 99991
2 44046  51.6296  10.9109 0007719 198.4927 161.4793 16.24256942  7383

KICKSAT 2                                                212 x 202 km

1 44046U 18092G   19090.74937422  .02794068  43485-2  95659-3 0 99993
2 44046  51.6295  10.5708 0007610 198.7465 161.2254 16.24595885  7396
KICKSAT 2                                                211 x 201 km
1 44046U 18092G   19090.81087801  .02876743  46339-2  95624-3 0 99992
2 44046  51.6294  10.2305 0007499 199.0005 160.9715 16.24944606  7403
KICKSAT 2                                                210 x 200 km
1 44046U 18092G   19090.87236840  .02965062  49495-2  95588-3 0 99995
2 44046  51.6293   9.8902 0007385 199.2545 160.7176 16.25303759  7413
KICKSAT 2                                                209 x 199 km
1 44046U 18092G   19090.93384498  .03059647  52997-2  95549-3 0 99997
2 44046  51.6292   9.5498 0007270 199.5085 160.4636 16.25674068  7427

KICKSAT 2                                                208 x 199 km

1 44046U 18092G   19090.99530733  .03160160  56089-2  95476-3 0 99996
2 44046  51.6291   9.2093 0007151 199.7627 160.2096 16.26056294  7431

KICKSAT 2                                                207 x 198 km

1 44046U 18092G   19091.05675499  .03267958  60368-2  95388-3 0 99993
2 44046  51.6290   8.8687 0007030 200.0170 159.9554 16.26451205  7445

KICKSAT 2                                                206 x 197 km

1 44046U 18092G   19091.11818745  .03391133  70756-2  95486-3 0 99997
2 44046  51.6288   8.5279 0006907 200.2713 159.7013 16.26860116  7457

KICKSAT 2                                                204 x 195 km

1 44046U 18092G   19091.17960418  .03525509  70970-2  95597-3 0 99995
2 44046  51.6287   8.1871 0006780 200.5257 159.4470 16.27284846  7461
KICKSAT 2                                                203 x 194 km
1 44046U 18092G   19091.24100455  .03661494  77126-2  95437-3 0 99997
2 44046  51.6286   7.8461 0006650 200.7802 159.1927 16.27726012  7476
KICKSAT 2                                                202 x 193 km
1 44046U 18092G   19091.30238795  .03809814  84159-2  95270-3 0 99992
2 44046  51.6284   7.5050 0006516 201.0348 158.9383 16.28184489  7486

KICKSAT 2                                                200 x 192 km

1 44046U 18092G   19091.36375371  .03973598  97252-2  95125-3 0 99998
2 44046  51.6283   7.1637 0006378 201.2896 158.6839 16.28661901  7491
KICKSAT 2                                                199 x 191 km
1 44046U 18092G   19091.42510107  .04162479  10742-1  95160-3 0 99999
2 44046  51.6282   6.8223 0006236 201.5444 158.4294 16.29160830  7503

KICKSAT 2                                                197 x 189 km

1 44046U 18092G   19091.48642918  .04372162  11932-1  95188-3 0 99995
2 44046  51.6280   6.4808 0006088 201.7993 158.1748 16.29684015  7510

KICKSAT 2                                                196 x 188 km

1 44046U 18092G   19091.54773710  .04606471  13599-1  95209-3 0 99995
2 44046  51.6278   6.1392 0005936 202.0544 157.9201 16.30234207  7527
KICKSAT 2                                                194 x 187 km
1 44046U 18092G   19091.60902376  .04870151  15334-1  95219-3 0 99992
2 44046  51.6277   5.7973 0005778 202.3095 157.6653 16.30814671  7532
KICKSAT 2                                                192 x 185 km
1 44046U 18092G   19091.67028797  .05169257  17435-1  95215-3 0 99994
2 44046  51.6275   5.4553 0005613 202.5648 157.4105 16.31429325  7545
KICKSAT 2                                                191 x 183 km
1 44046U 18092G   19091.73152837  .05511715  20017-1  95195-3 0 99991
2 44046  51.6273   5.1131 0005440 202.8202 157.1556 16.32082935  7550

KICKSAT 2                                                189 x 182 km

1 44046U 18092G   19091.79274341  .05908054  23241-1  95153-3 0 99994
2 44046  51.6271   4.7708 0005260 203.0758 156.9005 16.32781373  7561
KICKSAT 2                                                186 x 180 km
1 44046U 18092G   19091.85393131  .06372586  27343-1  95084-3 0 99996
2 44046  51.6269   4.4282 0005070 203.3316 156.6454 16.33532005  7577
KICKSAT 2                                                184 x 178 km
1 44046U 18092G   19091.91508999  .06839799  25626-1  93841-3 0 99998
2 44046  51.6267   4.0854 0004870 203.5875 156.3902 16.34340614  7585

KICKSAT 2                                                182 x 176 km

1 44046U 18092G   19091.97621733  .07361289  30852-1  92130-3 0 99998
2 44046  51.6264   3.7424 0004661 203.8435 156.1349 16.35207688  7592
KICKSAT 2                                                179 x 173 km
1 44046U 18092G   19092.03731096  .08062981  46253-1  91139-3 0 99998
2 44046  51.6261   3.3991 0004442 204.0998 155.8792 16.36146916  7605
KICKSAT 2                                                176 x 171 km
1 44046U 18092G   19092.09836773  .09004999  58934-1  90663-3 0 99998
2 44046  51.6258   3.0555 0004211 204.3563 155.6236 16.37186726  7615
KICKSAT 2                                                173 x 168 km
1 44046U 18092G   19092.15938338  .10233657  78703-1  90094-3 0 99996
2 44046  51.6255   2.7117 0003964 204.6130 155.3680 16.38356943  7621
KICKSAT 2                                                169 x 164 km
1 44046U 18092G   19092.22035237  .11926447  11224+0  89495-3 0 99993
2 44046  51.6251   2.3674 0003688 204.8700 155.1122 16.39701914  7632
KICKSAT 2                                                165 x 160 km
1 44046U 18092G   19092.28126699  .14500311  17680+0  89256-3 0 99990
2 44046  51.6247   2.0228 0003371 205.1273 154.8562 16.41299804  7645
KICKSAT 2                                                159 x 155 km
1 44046U 18092G   19092.34211551  .18800186  31496+0  87543-3 0 99994
2 44046  51.6241   1.6776 0002991 205.3850 154.6003 16.43300280  7654
KICKSAT 2                                                151 x 148 km
1 44046U 18092G   19092.40287790  .27700277  74422+0  69060-3 0 99999
2 44046  51.6234   1.3318 0002499 205.6432 154.3444 16.46046243  7663

See previous post for estimated decay sites ground track plot, as it's very similar compared to this case.

I will issue a new update tomorror Apr.1 at european evening.

Jon.

[Jon]

Hello all,

Right now KickSat-2 is passing the 200 Km barrier and will re-enter in the next hours. Here are the updated estimations:

SatEvo/SatAna: 2019 Apr. 2 @ 7h 17' UTC (+- 6 hours).

GMAT: 2019 Apr. 2 @ 9h 11' UTC (+- 6 hours).

As you can see in less that 16 hours between updates situation changed rapidly, and mean re-entry time advanced about 4 hours. I did not discard that re-entry time can be even nearer on time. This is the last chance to try to listen KickSat-2 for most part of the word!

I want to congratulate all the KickSat-2 team for the successful mission, and for making all this true. You have been the owners of 106 satellites!

I want to point that is very probable that we will never know the exact time (and because of that the place) where KickSat-2 re-entered. USPACECOM usually publishes re-entry time and place for the satellites that are massive enough. They know it because the re-entry can be detected by infrared millitary satellites that scans for missile and rocket launches. Hoewer, if the satellite is small, they can't detect it. All that they can do is to track KickSat-2 using their different radar stations in the word till they lost it, and then (typically) publish an estimation.

USPACECOM updated their estimations via TIP message 5 hours ago: 2019 Apr. 2 @ 5h 34' UTC.

Joseph Remis updated his estimations in his Twitter account about 4 hours ago: 2019 Apr. 2 @ 09h 22' UTC (+- 6 hours).

Here are updated integrated TLEs for forced decay at Apr. 2 @ 8h UTC, derived using SatEvo/SatAna. As I said in last days, Use them with caution, and each in the correct epoch. Allow some seconds of uncertainty in time and few degrees of uncertainty on track:

KICKSAT 2                                                203 x 191 km
1 44046U 18092G   19091.24089466  .04282240  11230-1  10504-2 0 99998
2 44046  51.6262   7.8436 0008863 213.3816 146.5627 16.28333413  7472
KICKSAT 2                                                201 x 190 km
1 44046U 18092G   19091.30225378  .04499010  12518-1  10505-2 0 99995
2 44046  51.6260   7.5023 0008653 213.6364 146.3086 16.28871982  7483
KICKSAT 2                                                200 x 189 km
1 44046U 18092G   19091.36359208  .04741440  14018-1  10506-2 0 99996
2 44046  51.6259   7.1608 0008436 213.8913 146.0547 16.29438490  7491
KICKSAT 2                                                198 x 187 km
1 44046U 18092G   19091.42490848  .05014445  15814-1  10505-2 0 99992
2 44046  51.6257   6.8192 0008210 214.1464 145.8008 16.30036340  7509
KICKSAT 2                                                196 x 186 km
1 44046U 18092G   19091.48620173  .05324417  17993-1  10502-2 0 99994
2 44046  51.6255   6.4774 0007975 214.4016 145.5468 16.30669620  7513
KICKSAT 2                                                194 x 184 km
1 44046U 18092G   19091.54747044  .05679698  20674-1  10497-2 0 99995
2 44046  51.6254   6.1354 0007729 214.6569 145.2927 16.31343307  7525
KICKSAT 2                                                192 x 182 km
1 44046U 18092G   19091.60871298  .06091393  24025-1  10490-2 0 99999
2 44046  51.6252   5.7932 0007471 214.9124 145.0386 16.32063550  7532
KICKSAT 2                                                190 x 180 km
1 44046U 18092G   19091.66992751  .06572886  28168-1  10477-2 0 99991
2 44046  51.6250   5.4508 0007199 215.1680 144.7845 16.32837988  7544
KICKSAT 2                                                187 x 178 km
1 44046U 18092G   19091.73111184  .07121101  27883-1  10422-2 0 99996
2 44046  51.6246   5.1082 0006911 215.4238 144.5303 16.33675971  7557
KICKSAT 2                                                185 x 176 km
1 44046U 18092G   19091.79226355  .07676079  33699-1  10226-2 0 99992
2 44046  51.6244   4.7654 0006609 215.6798 144.2760 16.34579776  7564
KICKSAT 2                                                182 x 174 km
1 44046U 18092G   19091.85338010  .08352572  37726-1  10025-2 0 99993
2 44046  51.6241   4.4222 0006292 215.9360 144.0217 16.35558097  7575
KICKSAT 2                                                179 x 171 km
1 44046U 18092G   19091.91445848  .09221305  61189-1  98473-3 0 99992
2 44046  51.6238   4.0788 0005957 216.1924 143.7673 16.36626181  7584
KICKSAT 2                                                175 x 168 km

1 44046U 18092G   19091.97549470  .10506302  81530-1  97988-3 0 99991

2 44046  51.6235   3.7351 0005599 216.4491 143.5128 16.37826396  7592

KICKSAT 2                                                171 x 165 km

1 44046U 18092G   19092.03648299  .12284674  11574+0  97465-3 0 99994
2 44046  51.6231   3.3910 0005202 216.7060 143.2584 16.39209860  7609
KICKSAT 2                                                167 x 160 km
1 44046U 18092G   19092.09741526  .14998714  18480+0  97295-3 0 99990
2 44046  51.6227   3.0464 0004745 216.9633 143.0040 16.40859009  7618
KICKSAT 2                                                161 x 155 km
1 44046U 18092G   19092.15827912  .19615184  33286+0  96364-3 0 99990
2 44046  51.6221   2.7014 0004195 217.2209 142.7500 16.42937398  7629
KICKSAT 2                                                153 x 148 km
1 44046U 18092G   19092.21905301  .29448834  80559+0  75306-3 0 99991
2 44046  51.6214   2.3557 0003476 217.4791 142.4966 16.45828681  7639
KICKSAT 2                                                138 x 135 km
1 44046U 18092G   19092.27968706  .70233682  49167+1  67101-3 0 99999
2 44046  51.6203   2.0088 0002299 217.7381 142.2457 16.51103503  7643

Here is the updated decay ground track. It was made using JSatTrak. I will make a final udate about the re-entry this european night. So, this is not the definitive decay ground track:

Jon.

[Jon]

Hello all,

This is probably the last re-entry prediction for KickSat-2. As I said in the previous post, the re-entry time is nearer than expected in previous days and hours. This is an update to the previous post, so some parts, excluding predictions, are copy-pasted.

As you can see in less that 21 hours between updates situation changed rapidly, and mean re-entry time advanced about 4 hours. I did not discard that re-entry time can be even nearer on time. This is the last chance to try to listen KickSat-2 for most part of the world! It will re-enter in ~7 hours after these lines are been wroten.

I want to congratulate all the KickSat-2 team for the successful mission, and for making all this true. You have been the owners of 106 satellites!

I want to point that is very probable that we will never know the exact time (and because of that the place) where KickSat-2 re-entered. USPACECOM usually publishes re-entry time and place for the satellites that are massive enough. They know it because the re-entry can be detected by infrared millitary satellites that scans for missile and rocket launches. Hoewer, if the satellite is small, they can't detect it. All that they can do is to track KickSat-2 using their different radar stations in the word till they lost it, and then (typically) publish an estimation.

Here predictions:

SatEvo/SatAna: 2019 Apr. 2 @ 06h 12' UTC (+- 4 hours).

GMAT: 2019 Apr. 2 @ 08h 00' UTC (+- 4 hours).

USPACECOM updated their estimations via TIP message 4 hours ago: 2019 Apr. 2 @ 05h 46' UTC.

Joseph Remis updated his estimations in his Twitter account about 10 hours ago: 2019 Apr. 2 @ 09h 22' UTC (+- 6 hours).

Here are updated integrated TLEs for forced decay at Apr. 2 @ 7h UTC, derived using SatEvo/SatAna. As I said in last days, Use them with caution, and each in the correct epoch. Allow some seconds of uncertainty in time and few degrees of uncertainty on track:

KICKSAT 2                                                190 x 179 km
1 44046U 18092G   19091.66989737  .06928321  31813-1  10765-2 0 99991
2 44046  51.6370   5.4691 0008059 234.0659 125.8593 16.33063918  7547
KICKSAT 2                                                187 x 177 km
1 44046U 18092G   19091.73107264  .07537540  31021-1  10697-2 0 99991
2 44046  51.6368   5.1265 0007722 234.3215 125.6066 16.33948879  7557
KICKSAT 2                                                184 x 175 km
1 44046U 18092G   19091.79221341  .08159665  37895-1  10474-2 0 99997
2 44046  51.6365   4.7836 0007367 234.5773 125.3541 16.34907337  7560
KICKSAT 2                                                181 x 172 km
1 44046U 18092G   19091.85331683  .08917182  42872-1  10233-2 0 99995
2 44046  51.6362   4.4405 0006994 234.8332 125.1012 16.35949674  7578
KICKSAT 2                                                178 x 169 km
1 44046U 18092G   19091.91437953  .09881069  69832-1  99941-3 0 99993
2 44046  51.6359   4.0971 0006598 235.0895 124.8485 16.37091998  7585
KICKSAT 2                                                174 x 166 km
1 44046U 18092G   19091.97539707  .11378082  95788-1  99281-3 0 99994
2 44046  51.6355   3.7533 0006171 235.3460 124.5959 16.38384225  7592
KICKSAT 2                                                170 x 162 km
1 44046U 18092G   19092.03636275  .13520893  14348+0  98604-3 0 99990
2 44046  51.6351   3.4091 0005689 235.6027 124.3435 16.39893305  7603
KICKSAT 2                                                165 x 158 km
1 44046U 18092G   19092.09726679  .16969159  23853+0  98363-3 0 99992
2 44046  51.6346   3.0644 0005124 235.8599 124.0915 16.41732207  7614
KICKSAT 2                                                158 x 152 km
1 44046U 18092G   19092.15809338  .23333043  47804+0  85095-3 0 99998
2 44046  51.6340   2.7192 0004424 236.1175 123.8404 16.44137593  7629
KICKSAT 2                                                147 x 143 km
1 44046U 18092G   19092.21881221  .39978895  15182+1  68651-3 0 99997
2 44046  51.6331   2.3731 0003436 236.3757 123.5915 16.47781450  7639
KICKSAT 2                                                105 x 104 km
1 44046U 18092G   19092.27931195 7.27841777  50000+2  13025-2 0 99994
2 44046  51.6331   2.0252 0000865 236.6353 123.3564 16.63394765  7648

Here is the updated decay ground track. It was made using JSatTrak. It covers the previous 3 and post 2 orbits respect the average of both SatEvo/SatAna and GMAT predictions:

It has been a pleasure. I wish we can meet in future KickSat missions!

Jon.

[Zac Manchester]

Thank you Jon!

<Auto Generated Inline Image 1.png>

It has been a pleasure. I wish we can meet in future KickSat missions!

Jon.

--

[Andy Thomas]

Thanks for all your predictions, Jon

andy G0SFJ

--

http://www.lulu.com/spotlight/andythomasmail

https://www.amazon.com/author/andythomas