Promise Tracker
The 2026 Earth to Mars transfer opportunity falls in late 2026: NASA's mission design handbook puts the lowest-energy departures on October 31 and November 14, 2026. In September 2024 Elon Musk wrote that the first Starships to Mars would launch in that window.
In February 2026 he wrote that SpaceX had shifted focus to a city on the Moon and would begin a Mars city in about five to seven years. SpaceX's S-1 filing (May 20, 2026) gives no Mars date. Starship first reached orbit on Flight 14 on September 28, 2026, deploying 26 Starlink V3 satellites, SpaceX reports; no Starship has transferred propellant in orbit.
Japan's MMX, which launches to Mars's moon Phobos on an H3 on October 20, 2026 (Japan time), will use this window. No Starship Mars launch is scheduled in it as of September 26, 2026.
Every row checked against its sources on Sep 26, 2026. Quotes are exact unless marked as a paraphrase; anything we could not confirm is flagged on the row. Download the ledger (CSV, CC BY 4.0)
| Promise | Made | Due | Status | Where it stands |
|---|---|---|---|---|
| Ship-to-ship propellant transfer test (Artemis lander milestone)NASA Office of Inspector General“This test was planned for March 2025 but has been delayed 12 months to March 2026.”NASA Office of Inspector General (Mar 10, 2026) | March 2026 (earlier March 2025) | Missed | Not attempted as of September 28, 2026. Starship first reached orbit on Flight 14 on September 28, 2026, a Starlink flight that did not include propellant transfer. | |
| Starship lunar lander critical design reviewNASA Office of Inspector General“CDR ... has been delayed to August 2026”NASA Office of Inspector General (Mar 10, 2026) · U.S. Government Accountability Office (Jul 23, 2026) | August 2026 | Came due, outcome not public | Came due August 31, 2026. We found no public confirmation either way; GAO (July 2026) said the lander's cost and schedule were under review.Not confirmed: Whether the review took place is not public. | |
| Catch the ship with the tower on the flight after Flight 13Elon Musk (reply on X)“Unless we discover problems after mission data review, SpaceX will attempt to catch the ship with the tower on next flight”Elon Musk on X (Jul 25, 2026) · SpaceNews (Aug 21, 2026, secondary) · Space.com (Sep 17, 2026, secondary) · SpaceX on X (Sep 28, 2026) · SpaceX on X (Sep 28, 2026) | next flight (Flight 14) | Revised | SpaceNews (August 21, 2026) reported the catch was off Flight 14; Space.com (September 17, 2026) reported both stages would splash down. Flight 14 flew on September 28, 2026 with no catch attempt: SpaceX reported the booster splashed down in the Gulf of America and the ship in the Pacific.Not confirmed: A new target (Flight 15) was reported from a podcast we could not check. | |
| Starship begins delivering payloads to orbit in the second half of 2026SpaceX (Form S-1)“We expect Starship to commence payload delivery to orbit in the second half of 2026 following additional flight tests.”SEC EDGAR (May 20, 2026) · SpaceX on X (Sep 28, 2026) · SpaceX on X (Sep 28, 2026) | second half of 2026 | Metdone Sep 28, 2026 | Met on September 28, 2026: SpaceX reported that Starship Flight 14 entered orbit and that all 26 Starlink V3 satellites it carried were deployed in orbit. | |
| Starlink V3 deployment on Starship begins in the second half of 2026SpaceX (Form S-1)“we expect to begin deploying on Starship in the second half of 2026”SEC EDGAR (May 20, 2026) · SpaceX on X (Sep 28, 2026) · SpaceX on X (Sep 28, 2026) | second half of 2026 | Metdone Sep 28, 2026 | Met on September 28, 2026: Flight 14 deployed 26 Starlink V3 satellites into orbit and the Starlink team made contact with all 26, SpaceX reports. Flight 13 (July 24, 2026) had released 20 V3 satellites on a path that brought them down by design. | |
| Long-duration flight test and propellant transfer test in 2026U.S. Government Accountability Office“Starship's next major flight milestones for the HLS are a long duration flight test and a propellant transfer test. Both tests are scheduled for 2026.”U.S. Government Accountability Office (Jul 23, 2026) | 2026 | Pending | GAO also says SpaceX is more than a year behind on these tests and the uncrewed landing; neither test has flown as of September 28, 2026. Flight 14 (September 28), Starship's first orbital flight, spent about 3 hours in orbit, SpaceX said, and did not include propellant transfer. | |
| Uncrewed Starship lunar landing demonstrationNASA Office of Inspector General“the uncrewed demonstration mission, which is expected to slip to the end of 2026”NASA Office of Inspector General (Mar 10, 2026) | end of 2026 | Pending | Depends on orbit, which Starship first reached on Flight 14 on September 28, 2026 (SpaceX), and on ship-to-ship transfer, not attempted as of September 28, 2026; SpaceX's own reported target is 2027. | |
| First uncrewed Starships launch to Mars in the 2026 windowElon Musk (post on X)“The first Starships to Mars will launch in 2 years when the next Earth-Mars transfer window opens.”Elon Musk on X (Sep 7, 2024) · Space.com (Sep 8, 2024, secondary) · Elon Musk on X (Feb 8, 2026) | the next Earth-Mars window (planning charts run to January 11, 2027) | Pending | Pending: the window runs to January 11, 2027 (NASA mission design handbook). On February 8, 2026 Musk wrote: "SpaceX has already shifted focus to building a self-growing city on the Moon". The S-1 (May 20, 2026) gives no Mars date.Not confirmed: No SpaceX statement cancelling or re-dating 2026 Mars ships was found, so the row stays pending until the window closes (review ruling, September 26, 2026). | |
| About five uncrewed Starships to Mars in 2026Elon Musk, as reported by ReutersParaphrase: SpaceX plans to send five uncrewed Starships to Mars in two years, Musk says (Reuters headline)Reuters (Sep 22, 2024, secondary) · Elon Musk on X (Feb 8, 2026) | in two years (2026 window, to January 11, 2027) | Pending | Pending: the window runs to January 11, 2027 (NASA mission design handbook). On February 8, 2026 Musk wrote: "SpaceX has already shifted focus to building a self-growing city on the Moon". The S-1 (May 20, 2026) gives no Mars date.Not confirmed: Reuters could not be fetched; the words are the headline, not Musk's own. | |
| Target the 2026/27 Mars window, with about even oddsElon Musk (SpaceX Mars update presentation)Paraphrase: Aimed to target the 2026/27 Mars window and put the chance at about 50% (our summary of the talk)SpaceX on X (May 29, 2025) · Wikipedia (Sep 26, 2026, secondary) · Elon Musk on X (Feb 8, 2026) | 2026/27 Mars window (to January 11, 2027) | Pending | Pending: the window runs to January 11, 2027 (NASA mission design handbook). On February 8, 2026 Musk wrote: "SpaceX has already shifted focus to building a self-growing city on the Moon". The S-1 (May 20, 2026) gives no Mars date. A 2028/29 fallback mentioned in the talk has not been restated.Not confirmed: The 42-minute video was not transcribed; the wording follows a secondary summary (Wikipedia, read September 26, 2026) and is a paraphrase, not a quote. | |
| Uncrewed Starship landing on the Moon as early as 2027SpaceX to investors, as reported by PayloadParaphrase: The company is now targeting an uncrewed landing on the Moon as early as 2027 (Payload's wording)Payload (Feb 9, 2026, secondary) | as early as 2027 | Pending | Depends on reaching orbit, which Starship first did on Flight 14 on September 28, 2026 (SpaceX), and on ship-to-ship propellant transfer, not attempted as of September 28, 2026.Not confirmed: The Wall Street Journal and Reuters reports behind this could not be fetched; the words are Payload's, not SpaceX's. | |
| First crewed Mars flights in the 2028 window, if 2026 landings succeedElon Musk (post on X)“If those landings go well, then the first crewed flights to Mars will be in 4 years.”Elon Musk on X (Sep 7, 2024) | in 4 years (2028 window), conditional | Pending | The condition, uncrewed landings in 2026, will not be met; the target has not been restated since February 8, 2026.Not confirmed: No explicit withdrawal found; it may fairly be treated as moot. | |
| Begin a Mars city in about five to seven years (after a Moon city)Elon Musk (post on X)“SpaceX will also strive to build a Mars city and begin doing so in about 5 to 7 years”Elon Musk on X (Feb 8, 2026) · Payload (Feb 9, 2026, secondary) · SEC EDGAR (May 20, 2026) | about 5 to 7 years | Pending | The current stated position as of September 26, 2026; the S-1 says only "eventually to reach Mars". |
These are left out of the ledger, or marked, rather than guessed. If you have a primary source, tell us.
2 of these rows are also on the Promise Ledger, which takes only verbatim quotes with a primary source and scores every agency, company and person by the same rules.
How it works: a promise is a dated public commitment by a company, agency or regulator, recorded with the date it was made and the date it was due. “Met late” means it happened after the date; “came due, not met” means the date passed without it. Statuses are re-checked against sources before the verified date moves. Cite as “SpaceNexus Promise Tracker: Starship and the 2026 Mars window” with the link. No sponsor sees or shapes this ledger.
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