Iridium Block 1 Constellation Status

Click here for the Block 1 Status Sheet

Here you find the current status of the Iridium Block 1 satellites according to my best knowledge as an Iridium Flare lover. It is not official information and not affiliated with Iridium Communications. Recent deorbit and re-entry events are based on current TLEs from and Twitter updates from @IridiumBoss, predicted reentry dates are estimates by SatFlare and

ATTENTION: Updates to the status sheet can only be accessed through this page. Every time I upload an update, the URL to the sheet changes. A bit annoying, but it’s the settings of the website that I cannot change. So in case you want to bookmark, choose THIS page (the one that you are currently reading).

Note on the Status Sheet: 

  • The blue block “Still flaring” shows the satellites that are still in a stable orbit and can flare reliably. Well, that is unfortunately ZERO now.
  • The gray block “Tumbling” includes the deorbiting satellites that have already been passivated. They are out of control but on a predictable trajectory, so you might see them tumble. This can produce brief flashes or even tiny flares somewhere along the trajectory.
    As long as SV 97 has not been passivated, it will do a series of burns to lower its orbit. Therefore the data you will be able to get will always lag behind and not give you accurate information.
  • The date format is European: DD.MM.YYYY, time reference is UTC.

Click here for the Block 1 Status Sheet

Last update:  30 May 2020

NEW: Note on update frequency

  • Since all the Block 1 satellites have now been deorbited, unfortunately there is not much to update:
  • Occasional updates will reflect changes in the estimated re-entry date of SV 96 which is currently predicted for around mid 2020.
  • After that, there will only be failed, tumbling Block 1 satellites left with rather distant reentry dates. I will still monitor them, but there will hardly ever be any data for updating the sheet!
  • So if you see an old date for the last update, the list is still alive and maintained! 

Some hints for watching tumbling satellites:

Most flare apps only showed active Iridium satellites and are therefore useless now.

The best and most reliable sources that still give you some input on tumbling satellites are: GoSatWatch for iOS. It is quite pricey however. There is a free trial though.
A good source for desktop is CalSky. But beware: It only shows Iridium satellites that have been actively reported by users as tumbling. So you still might miss out on the ones that do tumble (= all of them) but have not been reported. The site’s default setting is on “hobby astronomer”. You might want to select “astronomer” in order to get all results and decide yourself which ones are feasible for you.