zstarview

Zenith Star View is a desktop sky viewer for your chosen location.

It renders an all-sky view with stars, the Sun, Moon, planets, deep-sky objects, and guide overlays. When enabled, it can also add real-time cloud imagery, terrain horizon, urban outlines, night lights, nearby aircraft, and the ISS/JWST/Voyager 1/Voyager 2/Parker/Europa Clipper/Lucy/Psyche/JUICE/Solar Orbiter/BepiColombo artificial satellite overlays. Locations can be set by city or viewpoint name, direct coordinates, online place search, or supported Google Maps URLs.

Screenshots

The first screenshot shows the asterism overlay and also serves as a terrain-horizon example. The second screenshot shows the aircraft overlay together with the never-rises region. The third screenshot shows a denser star field rendered with -V10.5 -s5. The fourth screenshot shows zstarview-export-image --search "C/2023 R1" --sixel displaying a comet (C/2023 R1 Panstarrs) in a sixel terminal.

Note: higher magnitude limits increase rendering time. See about magnitude limit.

Urban outline and terrain horizon examples from several cities worldwide:

Circular Quay, Sydney	Near Tokyo Tower, Tokyo	View of Mt. Fuji, Japan	Marina Bay, Singapore

Near Burj Khalifa, Dubai	Jungfraujoch, Switzerland	Manarola, Italy	Sagrada Familia, Barcelona

Install

Recommended:

pipx install zstarview

Or with pip:

pip install zstarview

Note: The previous Windows on Arm64 installation blocker has been removed. Installation is now possible there, but Windows Security may still block Python extension modules during startup on some systems. If that happens, see the troubleshooting notes in the main project README.

First run check:

zstarview-gui

This opens the startup dialog first. If you select City as the location source and press Auto Search, the dialog fills in your current location automatically.

Prerequisite for the urban outline overlay:

For non-Arm64 platforms, install the overturemaps-py package with pipx:

pipx install overturemaps-py

On Windows Arm64, stage an x64 overturemaps v1.0.1 or newer release executable into the zstarview cache after installing zstarview with pipx; see Windows on Arm64 for the full steps and the dependency-wheel note.

Highlights

• Stars: the sky view shows stars from the selected catalog, with asterisms and other overlays layered on top.
• Solar-system bodies: supports Sun, Moon, and major planets.
• Deep-sky objects: named galaxies/open clusters/globular clusters are shown as soft blue extents.
• Asterism overlay: popular line patterns are shown as dim guide lines, alongside other sky guides such as the never-rises region, which uses a distinct neutral gray, plus the zenith and celestial pole markers.
• Satellite cloud imagery and sky-color disc: real-time Himawari/GOES satellite data are downloaded and rendered as a stylized hatched overlay, with the sky-color disc still visible beneath the clouds. The default width preset uses 50 stripes whose visible width varies with cloud amount. An experimental Geo-satellite path is available for Europe-band observers when --geo-satellite true is set.
• Aircraft and artificial satellite overlays: nearby aircraft from OpenSky can be drawn on the sky view, and ISS, JWST, Voyager 1, Voyager 2, Parker, Europa Clipper, Lucy, Psyche, JUICE, Solar Orbiter, and BepiColombo can be drawn as small purple markers between the planet and aircraft layers. ISS uses wheretheiss.at with CelesTrak fallback, while the other spacecraft use JPL Horizons.
• Tropical cyclone overlay: active hurricanes / typhoons from a public ArcGIS Active_Hurricanes_v1 FeatureServer can be shown as small markers with projected current-position tracking and a distance cutoff.
• Fresh current caches are reused for up to 24 hours for both the ISS cache and the Horizons-backed spacecraft cache.
• Terrain horizon and earth guide: Copernicus DEM data can be used to render the local terrain skyline and ground region, with a separate below-horizon continental hatch layer for orientation.
• Urban outline overlay: major rooflines are drawn for the current viewpoint, with optional distant skyscrapers in dense urban areas.
• Night lights overlay: The 2025 annual VIIRS Nighttime Lights VNL v2.2 GeoTIFF is downloaded from a GitHub Release on demand, cached locally, and rendered as a separate glow layer above the horizon and terrain ridges.
• Flexible location input: start from a city, tower, mountain, lat/lon, or online place/station search.
• Adjustable view center: change the view center from the CLI or with the arrow keys.
• Python support: routinely tested on CPython 3.10, 3.11, 3.12, 3.13, and 3.14.

Entry Points

This package provides three entry points:

• zstarview-gui for the interactive startup dialog and GUI launcher, with its own startup profile separate from the legacy CLI config.
• zstarview for GUI launches driven by command-line options, sharing the same option families described in the main README and the CLI reference docs.
• zstarview-export-image for headless one-shot image export, using the same option families as zstarview where applicable.

Code, Data Licenses, and Credits

• Code: MIT License. See LICENSE.
• Bundled and runtime-fetched data may be subject to their own licenses, attribution rules, or service terms.
• See the main project README for the full credits and third-party data notes.

Links

• Homepage: https://github.com/tos-kamiya/zstarview
• Documentation: https://github.com/tos-kamiya/zstarview#readme
• Issues: https://github.com/tos-kamiya/zstarview/issues