Open question · asked every run
Which planet has the most moons?
The right answer Saturn, with 293 confirmed moons as of August 2026.
Checked against JPL and NASA on Thu 5 Nov 2026
15 of 18 tries right in run 3 six apps · three tries each · Tue 3 Nov 2026
- ChatGPT
- Claude
- Copilot
- Gemini
- Grok
- Perplexity
Every answer that came back was right.
- ChatGPT: 3 of 3 right
- Claude: 3 of 3 right
- Copilot: 3 of 3 right
- Gemini: 3 of 3 right
- Grok: 0 of 3 right
- Perplexity: 3 of 3 right
Our view
Naming Saturn is the easy part. The count is where answers slip, because it keeps climbing and NASA's own pages can't agree on it.
Tip: Ask for the date the number is from, and trust the answer that can give you one.
dixon.ai, after run 3, Tue 3 Nov 2026
The official line
“Satellites of Saturn: 293”
“Saturn has 293 confirmed moons in its orbit as of August 2026, far more than any other planet in our solar system.”
The other planets
- Jupiter 115
- Uranus 29
- Neptune 16
- Mars 2
- Earth 1
- Mercury and Venus 0
We read it before and after every run, and the key follows the page.
What we asked, word for word
Which planet in our solar system has the most moons, and exactly how many confirmed moons does it have now?
The same words to all six apps, three times each, in fresh chats, with no follow-up. This question is open: its wording, every answer and the key are published every run.
Why this one can trip an AI
A figure an app learned in training is probably behind, and searching doesn't save it. NASA's Saturn moons page says 293 in the text but 274 in the summary that search results show, and its Saturn facts page still has the older figure. An app that reads the snippet says 274, in exactly the same tone.
“As of March 2025, Saturn had 274 confirmed moons in its orbit”
The count, drawn
293 dotsOne gold dot for every confirmed moon of Saturn.
Run 3 · Tue 3 Nov 2026
What each app said, in its own words
15 of 18 tries right. The other three, all Grok's, came back empty (its own failures: an error message or strings of unconnected words in place of an answer).
Every app on its free plan, signed in.
-
Saturn has 293 confirmed moons
ChatGPT, try 1, as captured -
The most recent figure I found is 293 moons with confirmed orbits as of June 2026.
Claude, try 1, as captured -
So the answer is: Saturn, with 293 confirmed moons.
Copilot, try 1, as captured -
Saturn has 293 confirmed moons with known orbits.
Gemini, try 1, as captured -
Nothing came back: Grok's own failures: an error message or strings of unconnected words in place of an answer
-
with 293 confirmed moons as of August 2026
Perplexity, try 1, as captured
Run 2 · Sun 11 Oct 2026
What each app said, in its own words
15 of 18 tries right. The other three, all Grok's, came back empty (its own error message).
Every app on its free plan, signed in.
-
Saturn has the most confirmed moons in our solar system, with exactly 293 confirmed moons as of October 2026.
ChatGPT, try 1, as captured -
Saturn has the most moons of any planet in the solar system. It currently has 293 confirmed moons
Claude, try 1, as captured -
Saturn has 293 confirmed moons as of August 2026, which is more than any other planet in the Solar System.
Copilot, try 1, as captured -
Saturn has 293 confirmed moons with established orbits.
Gemini, try 1, as captured -
Nothing came back: Grok's own error message, mostly after about ten minutes of working and on both tries, inside our 12-minute limit
-
Saturn has the most confirmed moons in the Solar System: 293 confirmed moons as of August 2026, according to NASA.
Perplexity, try 1, as captured
What else we noticed
- Gemini, try 2, got the answer right but said in passing: “(a): "easily outpacing Jupiter (which is second place with 101 confirmed moons)”
Run 1 · Sat 3 Oct 2026
What each app said, in its own words
16 of 18 tries right. The other two, both Grok's, came back empty (its own error message).
The pilot: the apps were on the plans we had that day, shown by each name. From run 2, every app is on its free plan.
-
Answer: 🪐 Saturn — 293 confirmed moons.
ChatGPT, try 1, as captured -
So 293 is the current confirmed figure, but it will likely keep rising.
Claude, try 1, as captured -
According to NASA, Saturn has 293 confirmed moons as of August 2026, which is more than any other planet in our Solar System.
Copilot, try 1, as captured -
It has 293 confirmed moons with recognized orbits.
Gemini, try 1, as captured -
Saturn has the most confirmed moons in our solar system, with 293 confirmed moons as of June 2026. ... but 293 is the widely cited current official figure for confirmed orbits.
Grok, try 1, as captured -
Saturn has the most confirmed moons of any planet in the Solar System: 293, as of June 2026.
Perplexity, try 1, as captured
What else we noticed
- All three of Perplexity's tries and Grok's one answer dated the figure June 2026; NASA's page says August. Right number, wrong month.
- One Perplexity try warned that older sources may still say 274, which is the trap, spotted and named.
Asking an AI something like this?
- Ask what date the number is from. A count that moves needs a date beside it.
- If two figures turn up, the newer one from the original source wins. Here that's JPL's table, which NASA's own page links to.
- Be wary of a round number. “About 290” sounds careful, but it answers a different question.
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