ALL ANSWERS · SPACE · DAILY No. 42 · OCTOBER 15, 2026
Size It Up Space answer: October 15
The five Space silhouettes for October 15, with the true sizes. If you have not played yet, this page is a spoiler — play these five first, then come back to argue with the numbers.
Day 42 ran from Atlas (30.2 km) to Kepler-22 (1,209,000 km). The widest gap was round 2, GJ 1214 against Kepler-22, at 4.0×; the closest call was round 5, Atlas against Prometheus, only 2.9× apart — the kind of round that separates a 90 from a 60.
SPOILER · TODAY’S FIVE
You have not finished today’s puzzle on this device. The answers below are blurred so you can still play first.
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ROUND 1
Oberon (Uranus’s moon · mean diameter) vs Mercury (mean diameter)
Mercury · reference · 4,879 km Oberon · true diameter · 1,523 km 3.2× shorter than Mercury
Oberon, a moon of Uranus, has a mean diameter of about 1,522.8 km. This is the body’s size, not an orbital distance.
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ROUND 2
GJ 1214 (estimated stellar diameter) vs Kepler-22 (estimated stellar diameter)
Kepler-22 · reference · 1,209,000 km GJ 1214 · true diameter · 300,800 km 4.0× shorter than Kepler-22
GJ 1214 has an estimated stellar diameter of about 300,820.7 km. This is the body’s size, not an orbital distance.
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ROUND 3
Moon (Earth’s moon · mean diameter) vs Ceres (mean diameter)
Ceres · reference · 939.4 km Moon · true diameter · 3,475 km 3.7× wider than Ceres
Moon, a moon of Earth, has a mean diameter of about 3,474.8 km. This is the body’s size, not an orbital distance.
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ROUND 4
Titan (Saturn’s moon · mean diameter) vs Rhea (Saturn’s moon · mean diameter)
Rhea · reference · 1,527 km Titan · true diameter · 5,150 km 3.4× wider than Rhea
Titan, a moon of Saturn, has a mean diameter of about 5,149.5 km. This is the body’s size, not an orbital distance.
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ROUND 5
Atlas (Saturn’s moon · mean diameter) vs Prometheus (Saturn’s moon · mean diameter)
Prometheus · reference · 86.2 km Atlas · true diameter · 30.2 km 2.9× shorter than Prometheus
Atlas, a moon of Saturn, has a mean diameter of about 30.2 km. This is the body’s size, not an orbital distance.
Beat these tomorrow
Every round is worth up to 100 points: within 6% of the true size scores 100, half or double scores 45, five times off scores zero. The daily puzzle is the same five for everyone and refreshes at midnight in your time zone; if you want more than five, Size It Up Unlimited draws fresh pairs from the whole library for as long as you like.