That Day – The Sky in History

Puzzles solved by the stars

Only for iPhone

9,00 kr · Designed for iPhone. Not verified for macOS.

iPhone

29 true moments, from the Titanic to the Moon landing. Read the puzzle, see the sky exactly as it was, and find the answer yourself. No ads, no account, fully offline. Why was the night the Titanic sank so dark? What was the bright star outside Van Gogh's window? What did Song dynasty astronomers see over Kaifeng in 1054? That Day is a collection of stories about real moments in history, each with a question that only the sky can answer. HOW IT WORKS • Read the puzzle: a short scene from history, and a question. • See the sky: the real sky above that place at that minute, calculated on your iPhone. Look around, follow the hints and move time forward or back. • Find the answer: the story explains what the sky shows, with the historical sources. 29 STORIES Art, history, literature and science, from 490 BC to 1969: • The moonless night of the Titanic • The guest star of 1054 over Kaifeng • Van Gogh's Starry Night and Moonrise • Monet's Impression, Sunrise • Bashō setting out on The Narrow Road to the Deep North • Su Shi's Red Cliff and his Mid-Autumn moon • Paul Revere's ride, the Moon landing, the discovery of Neptune, and more A REAL SKY, NOT AN ILLUSTRATION The Sun, Moon and planets are calculated with Astronomy Engine to about one arcminute. 5,044 stars and all 88 constellations come from a modern catalogue. The app handles the Julian calendar and ancient dates, and each story explains where the limits of the calculation matter. CAREFULLY SOURCED Every story lists its sources, from ship inquiries and observatory records to Chinese and Korean histories. All images are public domain. Where historians disagree, the story says so. QUIET BY DESIGN • One purchase, no in-app purchases, no ads, no subscription • No account and no data collected • Works fully offline • English, Simplified Chinese, Traditional Chinese, Japanese and Spanish

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    Information

    Size
    18.3 MB
    Category
    Education
    Compatibility
    Requires iOS 17.0 or later.
    • iPhone
      Requires iOS 17.0 or later.
    • Mac
      Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
    Languages
    English and 4 more
    • English, Japanese, Simplified Chinese, Spanish, Traditional Chinese
    Age Rating
    4+
    Provider
    Zishi Zang
    • Zishi Zang has identified itself as a trader for this app and confirmed that this product or service complies with European Union law.
    • Address
      China Mainland
      北京市
      北京市
      西城区马甸南村20号楼
      100088
    • Phone Number
      +86 15910694826
    • Email
      zangzishi@gmail.com
    Copyright
    © 2026 Zishi Zang
  • Privacy Policy

    • Supports

    • Family Sharing

      Up to six family members can use this app with Family Sharing enabled.