Welcome to Celesight Calendar and its mainland China website, provided by Suzhou Dongxuan Cultural Communication Co., Ltd. These terms explain the scope of the service, rules of use, and the rights and responsibilities of both parties.
1. Services
Celesight Calendar provides Gregorian and Chinese calendars, date cycles, solar terms, festivals and traditional almanac references, with anniversary reminders. Sky content includes Moon phases, Sun and Moon rise/set times, luminary positions, traditional star officials and the local meridian sky. The sky notebook includes historical-text search and local observing notes. Search original passages by phenomenon category, keyword or historical work, or begin a comparison from selected star officials or luminaries, retaining original dating and sources. Tools include a red light, dark-adaptation timer, telescope calculations and a choice of red or green appearance. The website provides product information, interface examples, Android downloads, guidance and policies.
The mainland China Android edition is the current primary platform. Some sky features require sign-in and an entitlement; their scope and duration are shown in the App. The website currently has no registration or sign-in service.
2. Use and accounts
Basic local calendar, almanac and reminder features do not require an account. When account services become available, the relevant pages will explain registration, entitlements and account deletion. Keep your account and device secure. Do not use another person's identity or maliciously interfere with the service.
3. Data and reminders
You choose dates, cities, observing times and reminder rules. Anniversaries and notes stay on your device, with no upload or cloud sync. Notes can contain text, selected photos and meridian chart images. Clearing App data or uninstalling removes local content, so retain your own important records. Device shutdown, power-saving policies, notification permission and background restrictions can affect delivery; independently check important reminders as needed.
4. Content and reasonable use
Almanac recommendations and traditional sky lore are cultural and reference material. Astronomy calculations depend on calendar conventions, location, time zone and the applicable range of the models. Ancient dates in particular require appropriate research context. Content is not medical or investment advice, or a guarantee of personal outcomes.
Historical-text search uses phenomenon categories, keywords and historical works. Original passages, annotations and table text retain their characters and include paragraph context, original dating and sources. Categories and word matches do not automatically identify separate astronomical events or establish that a passage describes the same phenomenon as the current chart. Read the annotations and original calendar context; do not infer unverified modern dates. You must have lawful rights to text and images you add. Custom tool or historical-text URLs open in a separate system browser window and cannot read local App records. External services have their own rules.
Use the software lawfully. Do not compromise security, steal accounts, bypass entitlements, distribute unlawful material, or infringe intellectual property or other legitimate rights.
5. Intellectual property
Product names, interface designs and content we create are protected under applicable law. Open-source components follow their own licenses, available in the App's About page. Using the service does not transfer our or third parties' intellectual property rights to you.
6. Updates and service changes
We may correct data or calculations, improve the interface and release updates. You must choose to install App updates. Important changes to services, rules or privacy practices will be explained on the relevant pages.
7. Responsibility and disputes
We take reasonable steps to keep the service available and address faults. Liability for events outside our control, device or network faults will be assessed under their actual causes and applicable law. These terms do not exclude liabilities that cannot legally be excluded. Contact us first to discuss a dispute. The laws of the People's Republic of China apply, and jurisdiction follows applicable legal rules.
8. Contact
Service provider: Suzhou Dongxuan Cultural Communication Co., Ltd.
Contact: info@tunghsuan.com
Updated: 2026-10-20.