- Earth-watching satellite
- MOS 1B (MOMO 1B)
- NORAD 20478
- 1990-013A
- Low Earth orbit
Current orbit
View on live mapOrbit began over the United States of America
Orbit ends over the Pacific Ocean
Sunlit since
Enters the Earth’s shadow
In view from you
Nobody watches Momo-1B go over, but a receiver still asks whether it is above the horizon. Say where you are and this card answers.
Your position is rounded to about a kilometre and sent only to the Orbinauts API, to find the pass.
No brightness has been published for Momo-1B, so it is not a naked-eye satellite and no city page carries pass times for it. Nothing here estimates one.
Seeing it
There is nothing to go outside for: it is too faint for the naked eye. What it is up there for reaches the ground as pictures and measurements, not as a light in the sky.
Timeline
- Launch
Launched, on the day GCAT records. Source
Summary
Over the Southern Ocean LIVE
Where is Momo-1B?
At 5:36:48 PM UTC Momo-1B was over the Southern Ocean (70.5° S, 145.3° W), 935 km up, moving at 7.38 km/s and in sunlight.
What is Momo-1B?
A satellite that watches the Earth in low Earth orbit, in space since Feb 7, 1990.
Can I see Momo-1B?
No, not with the naked eye: no brightness has been published for Momo-1B, and nothing here estimates one; what people use is its pictures and measurements of the Earth.
General
- Operator
- National Space Development Adminstration
- State
- Japan (Nippon), State of
- Built by
- Nippon Electric Corp., Space Div., Kamoi Works
- What it is
- Earth-watching satellite
- Launched
- Mass
- 740 kg
- Operating
- Orbit class
- Low Earth orbit
From GCAT, Jonathan McDowell’s general catalogue, licensed CC BY 4.0: the operator, the state, the manufacturer, what it is for, the launch day, the mass, and whether it is operating. The orbit class is read from its current elements.
Latest orbital data
- Position received
- 5:36 PM UTC
- Station time (UTC)
- 5:36 PM UTC
- Latitude / longitude
- 70.5° S, 145.3° W
- Altitude
- 935 km
- Speed
- 7.38 km/s (26,579 km/h)
- Course
- south-west
- Light
- In sunlight until 5:55 PM UTC
- Inclination
- 99.2°
- Orbital period
- 103.1 minutes
- Orbits per day
- 13.96
- This orbit
- 900 to 909 km
- In shadow
- 32 minutes of each orbit
- In view from
- Within 2,320 km of the point below it
- Elements epoch
- Nov 7, 2026, 2:36 PM, 1 day old
- Source
- Position from Space-Track orbital elements of Nov 7, 2026, 2:36 PM, 1 day old.
No operator publishes an ephemeris for Momo-1B, so every position here comes from its orbital elements.
In orbit
- Close approaches
- No close approach to Momo-1B has been reported publicly in the past thirty days.
From Space-Track’s public conjunction messages; the latest report was issued Nov 8, 2026, 1:11 PM, 3 hours old. Only approaches serious enough to be reported publicly are listed: within three days and, for two bodies near the Earth, closer than a kilometre with a chance of a collision above 1 in 10,000, the level at which NASA moves the ISS.
Launched with
Momo-1B shares its launch, 1990-013, with 3 other bodies the catalogue lists in orbit.
| Body | What it is |
|---|---|
| DEBUT (ORIZURU) | Satellite |
| JAS 1B (FUJI 2) | Communications satellite |
| H-1 R/B | Rocket body |
Read from the international designators of the US catalogue: the year and the launch number every piece of one launch shares. A body that has come down is no longer listed.
Beside the others
| Satellite | Typical altitude | Orbital period | Mass | In space since |
|---|---|---|---|---|
| Momo-1B | 900 to 909 km | 103 minutes | 740 kg | 1990 |
| Sentinel-5P | 826 to 828 km | 101 minutes | 820 kg | 2017 |
| Suomi NPP | 825 to 829 km | 101 minutes | about 2.1 t | 2011 |
| MetOp-SG A1 | 820 to 821 km | 101 minutes | about 4 t | 2025 |
| Metop-B | 818 to 823 km | 101 minutes | about 4.1 t | 2012 |
| Metop-C | 820 to 821 km | 101 minutes | about 4.1 t | 2018 |
Data and API
The current elements from Space-Track as an OMM object, epoch Nov 7, 2026, 2:36 PM, 1 day old.
{
"OBJECT_NAME": "MOS 1B (MOMO 1B)",
"OBJECT_ID": "1990-013A",
"EPOCH": "2026-11-07T14:36:27.156960",
"MEAN_MOTION": 13.96095791,
"ECCENTRICITY": 0.00060154,
"INCLINATION": 99.2022,
"RA_OF_ASC_NODE": 12.7484,
"ARG_OF_PERICENTER": 147.4054,
"MEAN_ANOMALY": 212.748,
"EPHEMERIS_TYPE": 0,
"CLASSIFICATION_TYPE": "U",
"NORAD_CAT_ID": 20478,
"ELEMENT_SET_NO": 999,
"REV_AT_EPOCH": 79204,
"BSTAR": 0.00024885471,
"MEAN_MOTION_DOT": 0.00000297,
"MEAN_MOTION_DDOT": 0
}