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  1. TESIGN / RADAR
  2. 2026.09.20
  3. Look4Sat

Look4Sat

See when a satellite passes overhead

WHO USES ITRadio amateurs, anyone trying to spot the ISS with the naked eye, and astronomy clubs.

Install to use

An Android satellite tracker that works out when the next pass crosses your sky, and where to look.

★ 1.5k▲ +6 / 7dDaily star increases over 14 days. Hollow bars mean no data. The last day may be partial.2026-09-06 no data2026-09-07 no data2026-09-08 no data2026-09-09 no data2026-09-10 no data2026-09-11 no data2026-09-12 no data2026-09-13 no data2026-09-14 no data2026-09-15 no data2026-09-16 +42026-09-17 +22026-09-18 no data2026-09-19 no datalargest one-day increase in the 14 days+4last 14 days · stars per dayhollow = no data

1,491 stars · checked on GitHub · 7-day +6 observed via GH Archive (as of )

RANKS SCIENCE #4

The Look4Sat map view: the ISS position and ground track over Europe, with azimuth, elevation, altitude and distance listed underneath.
The Look4Sat map view: the ISS position and ground track over Europe, with azimuth, elevation, altitude and distance listed underneath.
The Look4Sat map view: the ISS position and ground track over Europe, with azimuth, elevation, altitude and distance listed underneath.
The Look4Sat map view: the ISS position and ground track over Europe, with azimuth, elevation, altitude and distance listed underneath.

TESIGN TAKE

One map screen carries the satellite’s position along with azimuth, elevation and distance — exactly what you need to point an antenna.

INSTALL

AT A GLANCE

LICENSE
GPL-3.0
USAGE
Use freely. Release your source if you redistribute (copyleft).
LANGUAGE
Kotlin
PLATFORM
android
ACTIVITY
last commit within 24 h () · latest release v4.4.7 () · 24 releases
COMMUNITY
32 contributors · 37 open issues (incl. PRs) · made by: an individual
SOURCES
GitHub
OPEN SOURCE
YES
FIRST SEEN
CATEGORY
SCIENCE

A summary, not legal advice.

WHY IT MATTERS

To work a satellite on the radio, or just to see the ISS, you need to know when it passes and where to look. Look4Sat computes passes for more than 9,000 satellites from Celestrak and SatNOGS data, relative to your own position, and the maths runs offline — useful in a field with no signal.

BUILD FROM THIS

  • Kotlin and Jetpack Compose. There is a satellite list, upcoming passes, a polar radar view and a map, searchable by name or NORAD catalogue number. It predicts up to ten days ahead, shows pass progress with transceiver details, and accepts custom TLE files. It is ad-free and says it always will be.

WHO IT'S FOR

Radio amateurs, anyone trying to spot the ISS with the naked eye, and astronomy clubs.

START IN 5 MINUTES

# Install from Google Play, then set your station position in Settings — the predictions depend on it.

CAVEATS

  • Android only. A weekly TLE refresh is recommended for reliable predictions, and results are meaningless until you set your position. GPL-3.0: a modified build must be released under the same terms.

RECEIPT

FIRST SEEN
AT SOURCE
KEPT
CREATED → FIRST SEEN
2530d
WHEN FIRST SEEN
1,455 ★
SOURCES
GitHub

The same facts in machine-readable form — View as Markdown · JSON

SIMILAR TOOLS

Up to five from SCIENCE by ★ total: edited entries first, then repository cards; this entry is highlighted. Drawn from the same stored snapshot as the rankings — a comparison, not a recommendation.

IMAGENAME★ TOTAL▲ 7dLICENSEPLATFORMLAST PUSH
A frame from the README GIF: a 3D globe seen from orbit, overlaid with tracked-object labels and an orbit line.
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The AIPOCH Open-Science workspace: project and session list on the left, agent conversation and tool activity in the centre, generated tables and figures with the Provenance panel on the right
AIPOCH Open-ScienceAI research workbench for scientists★ 4.5k▲ +35Apache-2.0permissivemacos · windows · linux · cli
The Look4Sat map view: the ISS position and ground track over Europe, with azimuth, elevation, altitude and distance listed underneath.
Look4SatSee when a satellite passes overheadTHIS ENTRY★ 1.5k▲ +6GPL-3.0copyleftandroid
Solar Wanderer: Earth seen from the Moon's surface, with the Moon info panel (Chinese UI)
Solar WandererReal-time 1:1 solar system, no install★ 739—MITpermissiveweb

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