Week in Space Data, every Friday.
How often do SpaceX launch dates slip? As of Oct 8, 2026, SpaceX has flown 12 launches since we began recording launch dates on Aug 29, 2026: 10 of the 12 scored lifted off within a day of the first firm date on record, and 10 of 12 within a week; the median delay was 0 days. A launch whose date never moved while we watched counts as on time, so a launch added to the manifest days before it flew can look punctual.
How often do rocket launch dates slip? As of Oct 8, 2026, we have recorded 131 launch date changes on 79 launches since Aug 29, 2026. Counted our way (one launch's moves on one day netted into one), 10 were real slips: a day or more later, with both dates known to the day. A placeholder such as "NET 2026" rolling to "2027" is recorded but never counted as a slip.
Per-provider slip counts unlock at 25 real slips; the on-time record by provider and rocket is on the Launch Ledger.
Launch dates move constantly, and the history of those moves vanishes unless someone records it as it happens. We do: every change to a launch date in Launch Library 2 that our sync has seen since August 29, 2026 is logged when the sync sees it. A change made while we were not refreshing that launch is labelled “caught up” and not counted, because the day we saw it is not the day it happened. No revision feed exists upstream, so this ledger can't be backfilled by anyone. It only grows.
Only a move between two dates known to the day counts as a slip. A placeholder such as “NET 2026” rolling to “2027” is recorded and shown, never counted: how we classify every move. Frozen monthly and weekly editions: Slip Index and Slip Watch.
| Mission |
|---|
| Provider |
|---|
| From → To |
|---|
| Kind |
|---|
| Move |
|---|
| Observed |
|---|
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 9, 2026 → Oct 10, 2026 | Same-day change | +23.9 h later | Oct 8 |
| Falcon 9 Block 5 | Starlink Group 15-25 | SpaceX | Oct 10, 2026 → Oct 11, 2026 | Slip | +1 d later | Oct 7 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 8, 2026 → Oct 9, 2026 | Same-day change | +23.7 h later | Oct 7 |
| Nuri | NeonSat-2 to 6 | Korea Aerospace Research Institute | Oct 7, 03:23 → 03:25 UTC | Same-day change | 0 h earlier | Oct 7 |
| Atlas V N22 | Starliner-1 | United Launch Alliance | Dec 2026 → Jan 14, 2027 | Firmed | not a slip | Oct 7 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 6, 2026 → Oct 8, 2026 | Slip | +2 d later | Oct 6 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 5, 2026 → Oct 6, 2026 | Slip | +1 d later | Oct 5 |
| Falcon 9 Block 5 | Cygnus CRS-2 NG-25 | SpaceX | Dec 2026 → Nov 2026 | Placeholder roll | not a slip | Oct 4 |
| HANBIT-Nano | InnoSat-0 | Innospace | Nov 2026 → 2027 | Placeholder roll | not a slip | Oct 2 |
| Falcon 9 Block 5 | Dragon CRS-2 SpX-35 | SpaceX | Oct 2026 → Oct 13, 2026net of 3 moves that day | Firmed | not a slip | Oct 1 |
| GSLV Mk II | IRNSS-1L (NVS-03) | Indian Space Research Organization | Oct 13, 2026 → Oct 2026 | Lost its date | not a slip | Oct 1 |
| Falcon 9 Block 5 | Transporter 18 (Dedicated SSO Rideshare) | SpaceX | Oct 1, 18:18 → 18:32 UTCnet of 2 moves that day | Same-day change | +0.2 h later | Oct 1 |
| Falcon Heavy | Griffin Mission One | SpaceX | Nov 2026 → Dec 2026 | Placeholder roll | not a slip | Oct 1 |
| SR75 | Flight 2 | HyImpulse | Oct 5, 2026 → Q2 2027 | Lost its date | not a slip | Oct 1 |
| Falcon 9 Block 5 | Starlink Group 15-25 | SpaceX | Oct 10, 16:00 → 23:00 UTC | Same-day change | +7 h later | Sep 30 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 5, 08:06 → 08:16 UTC | Same-day change | +0.2 h later | Sep 30 |
| GSLV Mk II | IRNSS-1L (NVS-03) | Indian Space Research Organization | Oct 15, 2026 → Oct 13, 2026 | Pulled in | -1.3 d earlier | Sep 29 |
| Atlas V N22 | Starliner-6 | United Launch Alliance | Dec 31, 2028 (decade precision) → 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) → Dec 31, 2029 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-4 | United Launch Alliance | 2028 → Dec 31, 2029 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-3 | United Launch Alliance | 2027 → Dec 31, 2028 (decade precision) | Placeholder roll | not a slip | Sep 28 |
| Atlas V N22 | Starliner-2 | United Launch Alliance | 2027 → 2028 | Placeholder roll | not a slip | Sep 28 |
| Starship | Starlink Group 31-1 (Starship Flight 14) | SpaceX | Sep 28, 12:15 → 12:48 UTCnet of 2 moves that day | Same-day change | +0.6 h later | Sep 28 |
| PSLV-XL | EOS-10 (Oceansat-3A) | Indian Space Research Organization | Mar 2027 → Jan 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV | RISAT-2A | Indian Space Research Organization | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV | ConnectedCosmos | Indian Space Research Organization | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll | not a slip | Sep 26 |
| GSLV Mk II | IDRSS-2 | Indian Space Research Organization | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll | not a slip | Sep 26 |
| GSLV Mk II | IDRSS-1 | Indian Space Research Organization | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll | not a slip | Sep 26 |
| PSLV-XL | TDS-01 | Indian Space Research Organization | Dec 31, 2026 (placeholder) → Nov 2026 | Placeholder roll | not a slip | Sep 26 |
| LVM-3 | Gaganyaan-1 | Indian Space Research Organization | Dec 31, 2026 (placeholder) → Nov 2026 | Placeholder roll | not a slip | Sep 26 |
| Electron | Owlright, Owlright, Owlright (StriX Launch 13) | Rocket Lab | Sep 26, 00:26 → 00:39 UTC | Same-day change | +0.2 h later | Sep 25 |
| Falcon 9 Block 5 | USSF-385 | SpaceX | Sep 26, 11:56 → 14:00 UTCnet of 2 moves that day | Same-day change | +2.1 h later | Sep 25 |
| Falcon 9 Block 5 | SDA Tranche 1 Transport Layer A | SpaceX | Oct 31, 2026 (placeholder) → Oct 5, 2026 | Firmed | not a slip | Sep 25 |
| Ariane 64 Block 2 | Amazon Leo (LE-04) | Arianespace | Oct 7, 2026 → Oct 2026 | Lost its date | not a slip | Sep 25 |
| Falcon 9 Block 5 | Crew-14 | SpaceX | Dec 31, 2027 (placeholder) → Mar 2027 | Placeholder roll | not a slip | Sep 25 |
| Falcon 9 Block 5 | Transporter 18 (Dedicated SSO Rideshare) | SpaceX | Oct 1, 18:08 → 18:18 UTC | Same-day change | +0.2 h later | Sep 25 |
| Electron | Owlright, Owlright, Owlright (StriX Launch 13) | Rocket Lab | Sep 26, 00:15 → 00:26 UTC | Same-day change | +0.2 h later | Sep 24 |
| Falcon Heavy | NROL-97 | SpaceX | Oct 31, 2026 (placeholder) → Oct 2, 2026 | Firmed | not a slip | Sep 24 |
| Long March 8A | SatNet LEO Group 26 | China Aerospace Science and Technology Corporation | Sep 23, 13:30 → 13:33 UTC | Same-day change | +0.1 h later | Sep 23 |
| GSLV Mk II | IRNSS-1L (NVS-03) | Indian Space Research Organization | Dec 31, 2026 (placeholder) → Oct 15, 2026 | Firmed | not a slip | Sep 22 |
Caught up: the date changed while our sync was not refreshing this launch (or Launch Library 2 says it changed earlier), so the day we saw it is not the day it happened. Listed, never counted in weekly, monthly or quarterly figures. 29 in the ledger so far; the 29 most recently seen are below.
| Mission | Provider | From → To | Kind | Seen late on |
|---|---|---|---|---|
| SSLV | Space MAITRI | Indian Space Research Organization | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Soyuz 2.1a/Fregat-M | MKA Kinosputnik, KOEN and others | Russian Federal Space Agency (ROSCOSMOS) | Nov 19, 2026 → 2027 | Lost its date, caught up | Sep 24 |
| Neutron | Maiden Flight | Rocket Lab | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Long March 5 | Chang'e 7 | China Aerospace Science and Technology Corporation | Sep 30, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Firefly Alpha Block 2 | INCUS | Firefly Aerospace | Oct 31, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Falcon 9 Block 5 | Blue Ghost Lunar Lander Mission 2 | SpaceX | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Atlas V N22 | Starliner-2 | United Launch Alliance | Dec 31, 2026 (placeholder) → 2027 | Placeholder roll, caught up | Sep 24 |
| Falcon 9 Block 5 | KOMPSAT-7A | SpaceX | Nov 30, 2026 (placeholder) → Jun 2027 | Placeholder roll, caught up | Sep 24 |
| Vega-C | KOMPSAT-6 & PLATiNO 1 | Avio S.p.A | Nov 30, 2026 (placeholder) → Apr 2027 | Placeholder roll, caught up | Sep 24 |
| New Glenn | Blue Moon Pathfinder | Blue Origin | Sep 30, 2026 (placeholder) → Q1 2027 | Placeholder roll, caught up | Sep 24 |
| Falcon 9 Block 5 | Nova-C IM-3 | SpaceX | Dec 31, 2026 (placeholder) → Q1 2027 | Placeholder roll, caught up | Sep 24 |
| Falcon 9 Block 5 | 5x Astranis MicroGEO | SpaceX | Dec 31, 2026 (placeholder) → Q1 2027 | Placeholder roll, caught up | Sep 24 |
| Eris-1 | Flight Two | Gilmour Space Technologies | Dec 31, 2026 (placeholder) → Q1 2027 | Placeholder roll, caught up | Sep 24 |
| PSLV-XL | EOS-10 (Oceansat-3A) | Indian Space Research Organization | Mar 31, 2026 (placeholder) → Mar 2027 | Placeholder roll, caught up | Sep 24 |
| Firefly Alpha Block 2 | QuickSounder | Firefly Aerospace | Dec 31, 2026 (placeholder) → Feb 15, 2027 | Firmed, caught up | Sep 24 |
| Astra Rocket 4 | Maiden Flight | Astra Space | Dec 31, 2026 (placeholder) → Q1 2027 | Placeholder roll, caught up | Sep 24 |
| Falcon 9 Block 5 | SDA Tranche 2 Transport Layer C | SpaceX | Oct 31, 2026 (placeholder) → Jan 2027 | Placeholder roll, caught up | Sep 24 |
| Electron | Aspera | Rocket Lab | Dec 31, 2026 (placeholder) → Jan 29, 2027 | Firmed, caught up | Sep 24 |
| Vulcan | USSF-57 | United Launch Alliance | May 31, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| Vulcan | SDA Tranche 2 Transport Layer B | United Launch Alliance | Sep 30, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| Vulcan | SDA Tranche 1 Tracking Layer D | United Launch Alliance | Jun 30, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| Vulcan | SDA Tranche 1 Tracking Layer B | United Launch Alliance | Jun 30, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| Vulcan | NROL-64 | United Launch Alliance | Jun 30, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| Themis Demonstrator | T1H-1 | European Space Agency | Sep 30, 2026 (placeholder) → Q4 2026 | Placeholder roll, caught up | Sep 24 |
| RFA One | Maiden Flight | Rocket Factory Augsburg | Aug 31, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 24 |
| PSLV-XL | TDS-01 | Indian Space Research Organization | Mar 31, 2026 (placeholder) → Dec 31, 2026 (placeholder) | Placeholder roll, caught up | Sep 24 |
| New Glenn | Amazon Leo (LN-01) | Blue Origin | Jun 4, 2026 → 2026 | Lost its date, caught up | Sep 24 |
| Nebula-1 | Demo Flight | Deep Blue Aerospace | Jun 30, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 21 |
| Mir | Demo Flight | Agency for Defense Development | Aug 31, 2026 (placeholder) → 2026 | Placeholder roll, caught up | Sep 20 |
Per-provider slip stats (average slip, net days lost) unlock at 25 real slips; 10 so far. The on-time record by provider is already live on /launch-ledger. We'd rather show you a counter than dress days of data up as a verdict. The weekly chart below fills in on the same schedule.
SpaceNexus Launch Slip Explorer (live manifest observation; recording since Aug 29, 2026). https://spacenexus.us/launch-slips (retrieved 2026-10-08).
<iframe src="https://spacenexus.us/embed/chart/launch-slips-by-week" width="100%" height="360" frameborder="0" title="Launch Slip Explorer | SpaceNexus" loading="lazy"></iframe> <p style="font-size:12px"><a href="https://spacenexus.us/launch-slips">Launch Slip Explorer</a> · data by SpaceNexus</p>
Free to cite and embed with attribution. Data updates continuously; the citation date pins your retrieval.