Week in Space Data, every Friday.
On Sunday 27 September 2026, the ISS is visible from Tokyo at 6:18 PM GMT+9: it comes into view low in the north-northwest and reaches 26° above the horizon. It passes once more before dawn.
Tokyo, Japan: 35.68°N, 139.65°E (city centre). Recomputed every 15 minutes. Nothing on this page is sponsored.
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Sun 27 Sep, GMT+9 (09:18 UTC)
6:18 PM: it comes into view low in the north-northwest, climbs to 26°, halfway up in the northeast at 6:21 PM, then fades into Earth's shadow 17° up in the east at 6:23 PM.
6:18 PM: it comes into view low in the north-northwest, climbs to 26°, halfway up in the northeast at 6:21 PM, then fades into Earth's shadow 17° up in the east at 6:23 PM.
Full Moon, 99% lit
Rises , sets Mon 28 Sep at .
At dusk it is 4° up in the east. A bright Moon washes out faint stars and Hubble; the ISS and planets still show.
Last quarter: Sat 3 Oct at
Jupiter magnitude −1.9
Up from to ; highest while dark (38°) in the east at .
Sunset . Dark enough for the ISS from . Fully dark to . Sunrise . Times are GMT+9 unless you switch to UTC.
Satellite passes: CelesTrak orbital elements (we download them at most every 6 hours) propagated with SGP4; checked against Heavens-Above for 31 visible ISS passes over six cities (26 to 29 September 2026), start, highest point and end agreed within 5 seconds (usually 1 to 3) and height within half a degree, except that our darkness rule can start a twilight pass a few minutes later than Heavens-Above does. Times drift by up to a minute or two when elements are several days old or after the station changes its orbit, so we time passes only a few days ahead. A pass counts as visible when, at some point 10° or more above your horizon, the Sun is at least 6° below your horizon and the satellite is in sunlight; times and heights describe that visible part, and brightness is estimated from distance and sunlight angle. Moon and planets: computed with astronomy-engine. Launches: times to the minute only, within 400 km of the pad. Aurora: NOAA SWPC Kp and storm forecast, with an approximate geomagnetic latitude. Newest elements: epoch 2026-09-26 11:47 UTC. Computed 10:37 AM GMT+9.
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A good ISS pass reaches magnitude −2 to −4, brighter than any star; at its best only the Moon and Venus outshine it. A low or distant pass can be as faint as magnitude 0. It is a steady white point that does not blink and makes no sound. Tiangong is a step dimmer (about −1 to −3 on a high pass) and Hubble is a faint, steady star (about +1.5 to +2.5) that wants a dark sky. We estimate the brightness of each pass from its distance and the angle of sunlight on it, the method Heavens-Above uses, and our figures land within about half a magnitude of theirs.
A satellite is visible only while it is in sunlight and you are in darkness. When it flies into Earth's shadow it fades out over a few seconds, often still high in the sky. That is not cloud: it is orbital sunset. We show where and when each pass fades.
The ISS orbits at 51.6° inclination and its ground track drifts west about 22° each orbit, so it overflies Tokyo in runs of a week or two, then swings away for a similar stretch. Even when it does pass over, the Sun has to line up so the station is lit while your sky is dark. On nights with none, this page gives the next visible pass when there is one in the next three days; further out, pass times drift too much to print.
They are computed for Tokyo's coordinates with astronomy-engine, an open-source ephemeris checked against NASA JPL data to about an arcminute, so rise and set times are good to about a minute. A planet is listed when it is at least 10° above the horizon while the Sun is more than 6° below it.
northeast, 26° up
Fades
east, 17° up
Fades
east, 17° up
It fades out while still up: that is Earth's shadow, not cloud.
7:55 PM: it comes into view low in the west-northwest, climbs to 16°, low in the west at 7:56 PM, then fades into Earth's shadow 16° up in the west at 7:56 PM.
It fades out while still up: that is Earth's shadow, not cloud.
Saturn magnitude +0.2
Up from to ; highest while dark (57°) in the south at .
Mars magnitude +1.1
Up from to ; highest while dark (57°) in the east-southeast at .
Not in a dark sky tonight: Mercury, Venus.