KStars
What KStars is
KStars is free desktop planetarium software for exploring the sky and planning observing sessions. Its graphical simulation includes planets, comets, asteroids, up to 100 million stars, and 10,000 deep-sky objects. The observation planner arranges objects for a session and can download DSS images for offline comparison. For astrophotography, the Ekos suite includes workflows for polar alignment, focusing, auto-guiding, and image capture.
Through INDI, KStars supports astronomical equipment such as telescope mounts, focusers, filter wheels, and CCD and CMOS cameras. A built-in FITS Viewer displays FITS data files. Users can add custom catalogs; listed options include extra star catalogs reaching magnitude 16 and a default NGC/IC catalog of about 10,000 objects. Observation logs use the OAL XML schema, and D-Bus supports scriptable actions. KStars runs on Linux, macOS, and Windows. Its download page lists version 3.8.5, released on 3 October 2026, along with a source tarball.
Who it suits
KStars suits students, educators, amateur astronomers, and astronomy enthusiasts who want to explore the sky or plan observations. Its INDI support and Ekos workflow may also suit users working with astronomical equipment or astrophotography.
What it does well
- Free desktop planetarium software
- Simulates up to 100 million stars
- Observation planner can download DSS images for offline comparison
- Ekos includes astrophotography workflow tools
- Supports Linux, macOS, and Windows
What to know first
- Star-hopper routing is described as experimental and incomplete
- Observation logging needs more polish to be fully usable
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| KStars | Free astronomy software | Free |
As kstars.kde.org lists them, read 8 Oct 2026. The maker's own page has the final word.
Getting started
- Visit the KStars website.
- Choose a Windows, macOS, or Linux download.
- Install KStars on a desktop computer.
- Use the observation planner to arrange an observing session.
Verdict
KStars combines sky simulation, observing-session planning, and astronomy equipment support in a free desktop application. The site notes that star-hopper routing is experimental and observation logging still needs polish.
Questions
How much does KStars cost?
The listed KStars plan costs nothing, and the pricing model is free.
Is there a free plan or trial?
KStars has a free plan. There is no free trial.
Which platforms does KStars support?
KStars runs on Linux, macOS, and Windows.
Can KStars work offline?
Yes. Offline access is supported, and the observation planner can download DSS images for offline comparison.
Who makes KStars?
KStars is made by KDE. KDE e.V. is the registered non-profit representing the KDE Project in legal and financial matters.
Can KStars control telescope equipment?
Yes. Through INDI, it supports astronomical equipment including telescope mounts, focusers, filter wheels, and CCD and CMOS cameras.
Facts from KStars's own pages
- Astrophotography
- The Ekos suite provides an astrophotography workflow with polar alignment, focusing, auto-guiding and image capture. · kstars.kde.org, 8 Oct 2026
- Automation
- KStars supports scriptable actions using D-Bus. · kstars.kde.org, 8 Oct 2026
- Catalogs
- Users can add custom object catalogs; the site lists extra star catalogs reaching magnitude 16 and a default NGC/IC catalog of about 10,000 objects. · kstars.kde.org, 8 Oct 2026
- Downloads
- The KStars download page offers Windows, macOS and Linux downloads and a source tarball. · kstars.kde.org, 8 Oct 2026
- Equipment integration
- KStars uses INDI to support astronomical equipment including telescope mounts, focusers, filter wheels, and CCD and CMOS cameras. · kstars.kde.org, 8 Oct 2026
- FITS files
- KStars includes a FITS Viewer for viewing FITS data files. · kstars.kde.org, 8 Oct 2026
- Latest listed version
- The download page lists version 3.8.5, released on 3 October 2026. · kstars.kde.org, 8 Oct 2026
- Maker
- KStars is made by KDE; KDE e.V. is the registered non-profit representing the KDE Project in legal and financial matters. · ev.kde.org, 8 Oct 2026
- Notable limitations
- The site describes star-hopper routing as experimental and incomplete, and says observation logging needs more polish to be fully usable. · kstars.kde.org, 8 Oct 2026
- Observation logs
- KStars supports the OAL XML schema for observation logs, which the site says makes logs compatible with many software and log-sharing websites. · kstars.kde.org, 8 Oct 2026
- Observation planning
- Its observation planner orders objects for an observing session and can download DSS images for offline comparison. · kstars.kde.org, 8 Oct 2026
- Privacy
- KDE's software privacy policy says KDE software generally does not transmit information from users' devices except as a result of explicit user action, with some exceptions described in the policy. · kde.org, 8 Oct 2026
- Purpose
- KStars is desktop planetarium software for students, educators, amateur astronomers and astronomy enthusiasts. · kstars.kde.org, 8 Oct 2026
- Sky simulation
- It graphically simulates the sky, including planets, up to 100 million stars, 10,000 deep-sky objects, comets and asteroids. · kstars.kde.org, 8 Oct 2026
Where KStars stands on Freedom251
- Astronomy Apps#9 of 35