Help understanding how to look for evidence of TIDs in WSPR data

[Isobel Smith - 2E0YSI]

Hi all, 

I would like some help in understanding how to look for evidence for Travelling Ionospheric Disturbances in WSPR data. For context, I am interested in looking at the changes in radio propagation after a space shuttle launch (due to the Travelling Ionospheric Disturbances caused by the launch). 

The problem is, that I am not actually sure how to look for the evidence of TIDs in WSPR data. How I understand it, the travelling ionospheric disturbances affect the density of electrons in the ionosphere, so the effect on HF propagation can be enhanced, or weakened (more fading). Is it "enough" when we would observe some fading or enhanced propagation in the data?

Is just looking for abnormalities in the wider pattern good enough, or is this not the correct way to try to decipher the WSPR data? Should I limit the results to those below 3000km in distance, or is it okay to include multi-hop transmissions as well?

Thank you so much for reading through my email, any help, comments, or observations is much appreciated, I will include more information that I couldn't fit into this message below,

Thanks

Isobel Smith,
73 de M5DUK 

[ghby...@k9trv.org]

Dear Isobel,

 

I would think that to be a very difficult task.  There are no more space shuttle flights or launches, and when there were, there was not a wide and deep WSPR network, with the current level of multiband WSPR transmitters (often Turn Island Systems ‘wsprsonde’ units), nor multiband WSPR receivers (‘wsprdaemon’, often based on the Rx888 SDR device.)

 

The last shuttle flew in July of 2011.

 

73,

George K9TRV

--
Please follow the HamSCI Community Participation Guidelines at http://hamsci.org/hamsci-community-participation-guidelines.
---
You received this message because you are subscribed to the Google Groups "HamSCI" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hamsci+un...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/hamsci/0979845d-b5bb-45f0-af81-6d1d3a55e953n%40googlegroups.com.

[Isobel Smith - M5DUK]

Thank you for your reply. Perhaps "Space Shuttle" is the wrong terminology - I just meant any kindof spacecraft launch (e.g SpaceX launches). For example,  I initially just took the naive approach, of looking at the WSPR beacon data, with transmitters located around the site of the launch. As the locator for the Vandenberg Space Force Base in California is DM04AR, I decided to look at transmitters with maidenhead locators starting with DM, CM, DL, DN, EM and EN.

The launch I chose to look at was the SpaceX launch from the Vanderburg Space Force Base on the 06.11.2025 at 21:13 UTC.

The following graph shows the 20m band on the proceeding day of the launch (05.11.2025), the day of the launch (06.11.2025), and the following day (07.11.2025). 

​

The highlighted section on the 06/11/2025 after the launch (21:13) looks much more sparse when compared to the previous day, and the following day. That a change was observed, at roughly the time we expected it to occur, looked initially promising.

(I again reached the message limit so I will split this over yet another email).

[Isobel Smith - M5DUK]

However, according to the paper "First Observations of Large Scale Traveling Ionospheric Disturbances Using Automated Amateur Radio Receiving Networks" (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL097879 ), you should look at distances on the 20m band below 3000km to avoid transmissions with multi-hops. 

Therefore, when looking at the data for the 20m band again, with the distance reduced to below 3000km, you can see that the distances around 500km tend to increase on the 31.10.2025, compared to the day preceding and after it.

To make the data readable, the tx.loc was reduced to only include the maidenhead locators DM, CM, DL, DN.​

Thankyou once again for taking the time to look over the data, and please do let me know if you have any questions, 

Thanks,
Isobel de M5DUK

[Dr. Nathaniel A. Frissell Ph.D.]

Hi Isobel,

Have you read my 2022 Geophysical Research Letters paper? It is about identical large scale TIDs in WSPR/PSKReporter/RBN data.

I see that you are interested in TIDs related to a space shuttle launch. These are likely going to be small or medium scale TIDs, so I do not think my exact technique will work. In my paper, I plotted very large amounts of data together. Many of the smaller-scale features get washed out when you process the data the way that I did. Still, my paper may give you some ideas.

I think to see what you want, you would need to take a more finessed approach. I might look at individual pairs of stations that are transmitting across the region of interest and try to identify oscillatory behavior in some parameter. The WSPRDaemon group has specific stations that are keeping careful track of additional parameters that normal WSPR does not. These are likely useful here. Normally http://wsprdaemon.org/presentations.html is a good place to look for papers on this; it seems to be down right now. Gwyn Griffiths G3ZIL <gw...@autonomousanalytics.com>wrote most (all?) of them and will have good information.

Also note there is a tremendous amount of research on medium and smaller scale TIDs using GNSS Total Electron Content and SuperDARN. Just do a scholar.google.com search for this. My best SuperDARN MSTID work is available at https://doi.org/10.1002/2015JA022168.

Also, Grape Personal Space Weather Station Doppler data will likely be sensitive to this, also.

73 de Nathaniel W2NAF

From: ham...@googlegroups.com <ham...@googlegroups.com> on behalf of ghby...@k9trv.org <ghby...@k9trv.org>
Date: Tuesday, December 23, 2025 at 9:25 AM
To: ham...@googlegroups.com <ham...@googlegroups.com>
Subject: RE: [HamSCI] Help understanding how to look for evidence of TIDs in WSPR data

WARNING: This message originated from a source outside of the university.

To view this discussion visit https://groups.google.com/d/msgid/hamsci/015901dc7418%24036b6800%240a423800%24%40k9trv.org.

Please use your best judgment when opening attachments, clicking links, or replying to this email. If you suspect this is a phishing attempt, please forward to inf...@scranton.edu. Other questions can be directed to the Technology Support Center at (570) 941-4357 or techs...@scranton.edu.

[Gwyn Griffiths]

Hello Isobel

TIDs are certainly a fascinating subject and for your particular application I agree with Nathaniel that "a more finessed approach". A good starting would be a sketch showing what you can find out about a launch, you have got the launch site for starters, then find the direction of travel, as it might be important, when and how far 'down-range' does the rocket transit the E region at ~ 100 km high? 

A quick sketch for 6 November suggests to me the excellent Grape Personal Space Weather Station of W1EUJ which was at Oceanside, CA on 6 November. You can find its Doppler spectrograms at https://pswsnetwork.caps.ua.edu (you will need to 'register your station' if you have not used the site before), then navigate to the Observations tab and search for W1EUJ and start and stop of 5 and 7 November to get days either side. I'm looking at that data now, but I will let you draw your own conclusions about whether there were variations after 2113 UTC on 6 November above the background of WWV Doppler.

As for WSPR, Nathaniel mentioned how the enhanced data collection by WSPRDaemon users can be useful to study TIDs. It is well suited for 'a finessed approach' with just a single transmitter receiver pair. I've attached in a pdf an example of a type of medium scale TID observed in Doppler over the UK and with Total Electron Content anomaly maps to provide support as to what we were seeing.

Good luck with your studies.

Gwyn G3ZIL

[Isobel Smith - M5DUK]

Thank you so much for your replies. The papers you pointed out to me, Nathaniel, look very helpful, and the Grape Personal Space Weather Station looks to be an incredibly useful resource. I am not in academia, just an interested radio amateur, so being able to compare the doppler charts makes evaluating the data quite straightforward.

I hope you have a lovely festive season, 

Thankyou very much, 

Isobel M5DUK 

[Terry Bullett]

Isobel,

Another reference is some of my work:

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1002/2016GL070820

Good Luck,

Terry, W0ASP

To view this discussion visit https://groups.google.com/d/msgid/hamsci/ed805b6d-4597-4936-8fc7-f5bb4e04c218n%40googlegroups.com.

-- 
Dr. Terry Bullett          WØASP 
NOAA National Centers for Environmental Information (NOAA/NCEI)
Cooperative Institute for Research in Environmental Sciences (CIRES)
Terry....@noaa.gov    720-446-9775 (google voice)  978-337-9092 (cell)   
"Life is Complex.  It has a Real part and an Imaginary part." 

[isobel smith]

Thank you very much for all of your help, I finally managed to make some progress in looking into TIDs and SpaceX launches, and would appreciate some feedback as to whether you think my conclusions seem reasonable or not. 

My idea was to see if it would be possible to make QSO's based on the TIDs caused by SpaceX launches. Therefore, I decided to look into the WSPR data for 20m collected around the SpaceX launch on November 17, 2025 05:21 UTC, which was launched from the Vandenberg Base in California. I chose this launch because the time was at 21:21 PST. As propagation should be generally poorer at night for 20m, the disturbances should be fairly obvious.

Thanks to your previous advice, I looked into the GRAPE data from W1EUJ (https://pswsnetwork.eng.ua.edu/observations/observation_list/?station=324&startDate__gte=2025-11-15&endDate__lte=2025-11-19&latitude_min=&latitude_max=&longitude_min=&longitude_max=) situated at Oceanside, CA, (which should be close enough to pick up the SpaceX launch). The graphs look like this: 

There is a convincing spike around 6:00 UTC on the 17th, which would correlate with the SpaceX launch.

The next step was to look at the WSPP data for the 17th November. I used the GitHub repository (https://github.com/HamSCI/hamsci_LSTID_detection) created by HamSci to graph WSPR / PSKR and RBN data. I built graphs for the 20m band on the 16th, 17th. and 18th of November. (I should mention that I only looked at WSPR data as I was a bit lazy, and this API was easier for me to parse.) Following the logic from the "First Observations of Large Scale Traveling Ionospheric Disturbances Using Automated Amateur Radio Receiving Networks" paper, the data I used takes WSPR spots that are shorter than 3000km (to prevent that multi-hops are included in the data).

Encouragingly, there seems to be some nice activity around 6am on the 17th, that is not present on the 16th and 18th.

We also see that overall, more QSO's were made during 5:00 - 7:00 UTC on the 17th November, compared to the surrounding days:

Date | Record Count (05:00-07:00 UTC)

2025-11-15 | 20156 

2025-11-16 | 24687 

2025-11-17 | 39989 

2025-11-18 | 20145 

2025-11-19 | 16346 

2025-11-20 | 15800

I would expect that we should see some unusual variations in distances made for QSOs during the period after the launch. I looked at the propagation distances made by the transmitting station WW0WWV, (as they transmitted fairly frequently during that time period), and compared it to their QSOs made in previous two days, and the following two days for the time period 05:00 - 08:00:

To my untrained eye, it looks like there is a slightly wave-like trend in the data on the 17th November, where distances achieved are slightly higher on this day compared to the other days between ~6:00 and ~7:00 UTC. 

Would you also agree that it looks like these QSOs have been enabled by the TID caused by the SpaceX launch? Or have I made some critical errors somewjer

On 29. Jan 2026, at 20:39, 'Terry Bullett' via HamSCI <ham...@googlegroups.com> wrote:

 Isobel,

To view this discussion visit https://groups.google.com/d/msgid/hamsci/7b747e1f-3615-4f5a-9d82-2ede76e7d69e%40noaa.gov.

[Greg Beam]

Hi Isobel,                                                                                                                                                                                                                    

I run a propagation research lab with WSPR spot data (among others) in a local database. Your SpaceX TID work here on the HamSCI list caught my eye. The Sentinel-6B mission was interesting on a number of fronts.

I pulled WSPR 20m spot counts for 12 Vandenberg launches (2022-2025, refs in the readme), including your Sentinel-6B event. Each launch has a 3-hour window around launch time with ±3 day control periods, plus daily solar conditions (SFI, SSN, Kp) for context.

The dataset is here if useful:
https://github.com/IONIS-AI/ionis-jupyter/tree/main/data/vandenberg-tid

Two CSVs and a README. MIT licensed, use however you wish.

Sources:
- Band: WSPR 20m (band ID 107, 14.0956 MHz)
- Window: 3 hours starting at launch time (rounded to nearest hour)
- Control days: 3 days before and 3 days after launch, same hour window
- Solar data: GFZ Potsdam daily SFI/SSN, Kp daily average
- Source: 10.8 billion WSPR spots in ClickHouse (wspr.bronze), 2008-2026

73 de Greg Beam -- KI7MT

To view this discussion visit https://groups.google.com/d/msgid/hamsci/5615DF48-B9B4-481D-B2ED-A24DE382B918%40gmail.com.