Week in Space Data, every Friday.
Launch Slip Index · monthly
7 launch dates slipped a day or more in September 2026, across 5 launches, for 30.6 days in total. A slip here means both dates were known to the day; the 22 placeholder date rolls recorded in the month are shown at the bottom and not counted. 29 changes our sync saw late (made before the month or while we were not refreshing the launch) are listed separately and not counted.
Frozen edition. Published October 1, 2026; these figures will not change. Corrections, if any, are logged on /corrections.
| Mission | Provider | From, to | Kind | Move | Observed |
|---|---|---|---|---|---|
| Falcon 9 Block 5 | Starlink Group 15-25 | SpaceX | Sep 30, 2026 to Oct 10, 2026 | Slip | +9.3 d | Sep 21 |
| Soyuz 2.1b | Progress MS-35 (96P) | Russian Federal Space Agency (ROSCOSMOS) | Sep 9, 2026 to Sep 16, 2026 | Slip | +6.3 d | Sep 8 |
| Starship | Starlink Group 31-1 (Starship Flight 14) | SpaceX | Sep 22, 2026 to Sep 28, 2026net of 2 moves that day | Slip | +6 d | Sep 17 |
| Starship | Starlink Group 31-1 (Starship Flight 14) | SpaceX | Sep 18, 2026 to Sep 22, 2026 | Slip | +4 d | Sep 14 |
| Starship | Starlink Group 31-1 (Starship Flight 14) | SpaceX | Sep 15, 2026 to Sep 18, 2026 | Slip | +3 d | Sep 10 |
| Spectrum | Onward and Upward | Isar Aerospace | Sep 4, 2026 to Sep 5, 2026 | Slip | +1 d | Sep 4 |
| Long March 4B | Yaogan 53-01 to 03/56-01 to 03 | China Aerospace Science and Technology Corporation | Sep 9, 2026 to Sep 10, 2026 | Slip | +1 d | Sep 7 |
| Provider | Slips | Launches slipped | Days lost | Median slip | Pulled in | Same-day | Firmed | Lost a date | Placeholder rolls |
|---|---|---|---|---|---|---|---|---|---|
| SpaceX | 4 | 2 | 22.3 | 5 d | 0 | 15 | 6 | 0 | 4 |
| Russian Federal Space Agency (ROSCOSMOS) | 1 | 1 | 6.3 | 6.3 d | 0 | 1 | 0 | 0 | 0 |
| China Aerospace Science and Technology Corporation | 1 | 1 | 1 | 1 d | 0 | 3 | 1 | 1 | 1 |
| Isar Aerospace | 1 | 1 | 1 | 1 d | 0 | 1 | 0 | 0 | 0 |
| Arianespace | 0 | 0 | 0 | n/a | 0 | 0 | 0 | 1 | 0 |
| CAS Space | 0 | 0 | 0 | n/a | 0 | 1 | 0 | 0 | 0 |
| ExPace | 0 | 0 | 0 | n/a | 0 | 1 | 0 | 0 | 0 |
| Indian Space Research Organization | 0 | 0 | 0 | n/a | 1 | 0 | 1 | 0 | 7 |
| Orienspace Technology | 0 | 0 | 0 | n/a | 0 | 1 | 0 | 0 | 0 |
| Rocket Lab | 0 | 0 | 0 | n/a | 0 | 5 | 3 | 0 | 3 |
| Russian Space Forces | 0 | 0 | 0 | n/a | 0 | 0 | 1 | 0 | 1 |
| United Launch Alliance | 0 | 0 | 0 | n/a | 0 | 0 | 0 | 0 | 6 |
| Provider | Flew | Scored | Within 1 day | Within 7 days | Average delay | Median delay |
|---|---|---|---|---|---|---|
| All providers | 27 | 26 | 85% | 92% | +1.4 d | 0 d |
| SpaceX | 8 | 8 | 88% | 88% | +1.7 d | 0 d |
| China Aerospace Science and Technology Corporation | 5 | 5 | 80% | 80% | +2.6 d | 0 d |
| Rocket Lab | 4 | 4 | 75% | 100% | +0.5 d | 0 d |
| Avio S.p.A | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| CAS Space | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| ExPace | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| Galactic Energy | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| Indian Space Research Organization | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| Isar Aerospace | 1 | 1 | too few (1) | too few (1) | +1 d | +1 d |
| LandSpace | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| Orienspace Technology | 1 | 1 | too few (1) | too few (1) | 0 d | 0 d |
| Russian Federal Space Agency (ROSCOSMOS) | 1 | 1 | too few (1) | too few (1) | +6.9 d | +6.9 d |
| Russian Space Forces | 1 | 0 | none scored | none scored | n/a | n/a |
Shares are shown once a group has 3 or more scored launches. Delay is liftoff minus the first firm date on record; negative means it flew early.
| Mission | Provider | From, to | Kind | Move | Observed |
|---|---|---|---|---|---|
| GSLV Mk II | IRNSS-1L (NVS-03) | Indian Space Research Organization | Oct 15, 2026 to Oct 13, 2026 | Pulled in | -1.3 d | Sep 29 |
| Mission | Provider | From, to | Kind | Move | Observed |
|---|---|---|---|---|---|
| Ariane 64 Block 2 | Amazon Leo (LE-04) | Arianespace | Oct 7, 2026 to Oct 2026 | Lost its date | not a slip | Sep 25 |
| Long March 8A | SatNet LEO Group 26 | China Aerospace Science and Technology Corporation | Sep 11, 2026 to Sep 30, 2026 (placeholder) | Lost its date | not a slip | Sep 9 |
Launch Library parks an undated launch at the end of a period (“NET 2026” is stored as Dec 31, 2026). When that placeholder moves, nothing was announced and nothing slipped, so these rows are listed for completeness and never counted.
| Mission | Provider | From, to | Kind | Move | Observed |
|---|---|---|---|---|---|
| Atlas V N22 | Starliner-6 | United Launch Alliance | Dec 31, 2028 (decade precision) to Dec 31, 2030 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-5 | United Launch Alliance | Dec 31, 2028 (decade precision) to Dec 31, 2029 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-4 | United Launch Alliance | 2028 to Dec 31, 2029 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-3 | United Launch Alliance | 2027 to Dec 31, 2028 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-2 | United Launch Alliance | 2027 to 2028 | Placeholder roll | not a slip | Sep 28 |
| PSLV-XL | EOS-10 (Oceansat-3A) | Indian Space Research Organization | Mar 2027 to Jan 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV | RISAT-2A | Indian Space Research Organization | Dec 31, 2026 (placeholder) to 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV | ConnectedCosmos | Indian Space Research Organization | Dec 31, 2026 (placeholder) to 2027 | Placeholder roll | not a slip | Sep 26 |
| GSLV Mk II | IDRSS-2 | Indian Space Research Organization | Dec 31, 2026 (placeholder) to 2027 | Placeholder roll | not a slip | Sep 26 |
| GSLV Mk II | IDRSS-1 | Indian Space Research Organization | Dec 31, 2026 (placeholder) to 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV-XL | TDS-01 | Indian Space Research Organization | Dec 31, 2026 (placeholder) to Nov 2026 | Placeholder roll | not a slip | Sep 26 |
| LVM-3 | Gaganyaan-1 | Indian Space Research Organization | Dec 31, 2026 (placeholder) to Nov 2026 | Placeholder roll | not a slip | Sep 26 |
| Falcon 9 Block 5 | Crew-14 | SpaceX | Dec 31, 2027 (placeholder) to Mar 2027 | Placeholder roll | not a slip | Sep 25 |
| Vulcan VC6L | Amazon Leo (LV-01) | United Launch Alliance | Sep 30, 2026 (placeholder) to Oct 2026 | Placeholder roll | not a slip | Sep 20 |
| Long March 12A | Flight 2 | China Aerospace Science and Technology Corporation | Sep 30, 2026 (placeholder) to Oct 2026 | Placeholder roll | not a slip | Sep 20 |
| Electron | LOXSAT 1 | Rocket Lab | Sep 30, 2026 (placeholder) to 2026 | Placeholder roll | not a slip | Sep 19 |
| Electron | BlackSky Gen-3 6 | Rocket Lab | Sep 30, 2026 (placeholder) to 2026 | Placeholder roll | not a slip | Sep 19 |
| Electron | 6x HawkEye 360 | Rocket Lab | Sep 30, 2026 (placeholder) to 2026 | Placeholder roll | not a slip | Sep 19 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Sep 30, 2026 (placeholder) to Oct 31, 2026 (placeholder) | Placeholder roll | not a slip | Sep 18 |
| Soyuz 2.1b/Fregat | Glonass-K1 No. 20 (?) | Russian Space Forces | Dec 31, 2026 (placeholder) to Sep 30, 2026 (placeholder) | Placeholder roll | not a slip | Sep 17 |
| Falcon 9 Block 5 | Crew-13 | SpaceX | Sep 30, 2026 (placeholder) to Oct 31, 2026 (placeholder) | Placeholder roll | not a slip | Sep 16 |
| Falcon 9 Block 5 | 5x Astranis MicroGEO | SpaceX | Sep 30, 2026 (placeholder) to Dec 31, 2026 (placeholder) | Placeholder roll | not a slip | Sep 10 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 31, 2026 (placeholder) to Oct 5, 2026 | Firmed | not a slip | Sep 25 |
| Falcon Heavy | NROL-97 | SpaceX | Oct 31, 2026 (placeholder) to Oct 2, 2026 | Firmed | not a slip | Sep 24 |
| GSLV Mk II | IRNSS-1L (NVS-03) | Indian Space Research Organization | Dec 31, 2026 (placeholder) to Oct 15, 2026 | Firmed | not a slip | Sep 22 |
| Falcon 9 Block 5 | Transporter 18 (Dedicated SSO Rideshare) | SpaceX | Oct 31, 2026 (placeholder) to Oct 1, 2026 | Firmed | not a slip | Sep 21 |
| Electron | Owlright, Owlright, Owlright (StriX Launch 13) | Rocket Lab | Dec 31, 2026 (placeholder) to Sep 26, 2026net of 2 moves that day | Firmed | not a slip | Sep 19 |
| Falcon 9 Block 5 | Crew-13 | SpaceX | Oct 31, 2026 (placeholder) to Oct 1, 2026 | Firmed | not a slip | Sep 18 |
| Long March 8A | SatNet LEO Group 26 | China Aerospace Science and Technology Corporation | Sep 30, 2026 (placeholder) to Sep 23, 2026 | Firmed | not a slip | Sep 18 |
| Soyuz 2.1b/Fregat | Glonass-K1 No. 20 (?) | Russian Space Forces | Sep 30, 2026 (placeholder) to Sep 17, 2026 | Firmed | not a slip | Sep 18 |
| Electron | Owl By The Dozen (StriX Launch 12) | Rocket Lab | Oct 31, 2026 (placeholder) to Sep 19, 2026 | Firmed | not a slip | Sep 15 |
| Electron | Happily Ever Faster (BlackSky Gen-3 5) | Rocket Lab | Sep 30, 2026 (placeholder) to Sep 11, 2026 | Firmed | not a slip | Sep 11 |
| Starship | Starlink Group 31-1 (Starship Flight 14) | SpaceX | Sep 30, 2026 (placeholder) to Sep 15, 2026 | Firmed | not a slip | Sep 8 |
| Falcon 9 Block 5 | O3b mPower 11-13 | SpaceX | Sep 30, 2026 (placeholder) to Sep 13, 2026 | Firmed | not a slip | Sep 4 |
These date changes were recorded in this period but did not happen in it: the launch was outside the part of the manifest our sync was refreshing when its date changed, so we only saw the change later. They are listed so nothing is hidden, and are in none of the figures above.
| Mission | Provider | From, to | Kind | Move | Observed |
|---|---|---|---|---|---|
| SSLV | Space MAITRI | Indian Space Research Organization | Dec 31, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Soyuz 2.1a/Fregat-M | MKA Kinosputnik, KOEN and others | Russian Federal Space Agency (ROSCOSMOS) | Nov 19, 2026 to 2027 | Lost its dateCaught up: seen late | not counted | Sep 24 |
| Neutron | Maiden Flight | Rocket Lab | Dec 31, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Long March 5 | Chang'e 7 | China Aerospace Science and Technology Corporation | Sep 30, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Firefly Alpha Block 2 | INCUS | Firefly Aerospace | Oct 31, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Falcon 9 Block 5 | Blue Ghost Lunar Lander Mission 2 | SpaceX | Dec 31, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Atlas V N22 | Starliner-2 | United Launch Alliance | Dec 31, 2026 (placeholder) to 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Falcon 9 Block 5 | KOMPSAT-7A | SpaceX | Nov 30, 2026 (placeholder) to Jun 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Vega-C | KOMPSAT-6 & PLATiNO 1 | Avio S.p.A | Nov 30, 2026 (placeholder) to Apr 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| New Glenn | Blue Moon Pathfinder | Blue Origin | Sep 30, 2026 (placeholder) to Q1 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Falcon 9 Block 5 | Nova-C IM-3 | SpaceX | Dec 31, 2026 (placeholder) to Q1 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Falcon 9 Block 5 | 5x Astranis MicroGEO | SpaceX | Dec 31, 2026 (placeholder) to Q1 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Eris-1 | Flight Two | Gilmour Space Technologies | Dec 31, 2026 (placeholder) to Q1 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| PSLV-XL | EOS-10 (Oceansat-3A) | Indian Space Research Organization | Mar 31, 2026 (placeholder) to Mar 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Firefly Alpha Block 2 | QuickSounder | Firefly Aerospace | Dec 31, 2026 (placeholder) to Feb 15, 2027 | FirmedCaught up: seen late | not counted | Sep 24 |
| Astra Rocket 4 | Maiden Flight | Astra Space | Dec 31, 2026 (placeholder) to Q1 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Falcon 9 Block 5 | SDA Tranche 2 Transport Layer C | SpaceX | Oct 31, 2026 (placeholder) to Jan 2027 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Electron | Aspera | Rocket Lab | Dec 31, 2026 (placeholder) to Jan 29, 2027 | FirmedCaught up: seen late | not counted | Sep 24 |
| Vulcan | USSF-57 | United Launch Alliance | May 31, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Vulcan | SDA Tranche 2 Transport Layer B | United Launch Alliance | Sep 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Vulcan | SDA Tranche 1 Tracking Layer D | United Launch Alliance | Jun 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Vulcan | SDA Tranche 1 Tracking Layer B | United Launch Alliance | Jun 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Vulcan | NROL-64 | United Launch Alliance | Jun 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| Themis Demonstrator | T1H-1 | European Space Agency | Sep 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| RFA One | Maiden Flight | Rocket Factory Augsburg | Aug 31, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| PSLV-XL | TDS-01 | Indian Space Research Organization | Mar 31, 2026 (placeholder) to Dec 31, 2026 (placeholder) | Placeholder rollCaught up: seen late | not counted | Sep 24 |
| New Glenn | Amazon Leo (LN-01) | Blue Origin | Jun 4, 2026 to 2026 | Lost its dateCaught up: seen late | not counted | Sep 24 |
| Nebula-1 | Demo Flight | Deep Blue Aerospace | Jun 30, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 21 |
| Mir | Demo Flight | Agency for Defense Development | Aug 31, 2026 (placeholder) to 2026 | Placeholder rollCaught up: seen late | not counted | Sep 20 |
Method v1.1: how moves are classified and launches scored. Data: Launch Library 2 (The Space Devs, a volunteer nonprofit; support them on Patreon) manifest, observed and recorded by SpaceNexus since August 29, 2026. Licence CC BY 4.0: cite “SpaceNexus Launch Ledger”. No sponsor sees or shapes this ledger (policy).