You asked about Space Exploration
13 people built something like it. 13 are gone.
That is 100% of the ones whose fate we could settle, against 23% across the whole register.
| Launched | What it was | Today |
|---|---|---|
| 2019-01-01 | The Rocket Network: Sustainable & On-Demand Delivery Anywhere in Space · spaceryde.com | gone |
| 2015-01-01 | Launch small satellites · bagaveev.com | gone |
| 2020-01-01 | Developing supersonic UAVs as a pathway to quiet supersonic flight · exosonic.com | gone |
| 2021-06-01 | AI-Driven Tech & Space Optimization to Scale Restaurants · onestopkitchen.com | gone |
| 2020-06-01 | we're the place where people build cool shit. · buildspace.so | gone |
| 2019-01-01 | YCCapture All your notes, tasks, and files in one super-fast workspace. · capture.so | gone |
| 2020-06-01 | YCNototo A workspace with a spatial interface · nototo.app | gone |
| 2017-06-01 | Passerine Aircraft is building the next generation of dronesWe are… · passerineaircraft.com | gone |
| 2016-06-01 | YCReebeez Reebeez creates powerful microengines for UAVs. With a 2hr + flight… · reebeez.co | gone |
| 2026-01-01 | Custom Aerospace-Grade Battery Packs · kytentech.com | gone |
| 2023-01-01 | demospace.ai | gone |
| 2009-01-01 | spaceslife.com | gone |
| 2019-01-01 | YCBlitzIQ Note taking workspace for B2B sales teams · blitziq.com | gone |
How this compares
The register re-probes every domain it holds. Some that answered last month stop answering. We send that list — what went quiet, and what it was — once a month. Nothing else.
How this was made. Show HN entries are every post from 2021 to 2023 with at least five points that linked to its own domain; code hosts and free hosting are excluded, because a repository outlives the effort behind it. Product Hunt entries needed 100 votes — a far higher bar, so they are the promoted top slice rather than a like-for-like sample. Both are judged by asking the domain whether it still answers: gone means it no longer resolves, refuses the connection, serves a parking page, or says plainly that it shut down. An HTTP error is not counted as gone — a server answering 404 is one somebody still pays for, and an audit of 25 gone-calls found two such sites alive with only a moved homepage. Y Combinator entries use the status YC publishes itself, which is why only those can say acquired. Squatted domains — a lapsed name now serving somebody else's site — are not detected, so these figures run slightly low.