- Space telescope
- NORAD 2142
- 1966-031A
- Low Earth orbit
Current orbit
View on live mapOrbit began over Brazil
Orbit ends over Brazil
In the Earth’s shadow since
Back in sunlight
In view from you
Nobody watches OAO 1 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 OAO 1, 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 far too faint for the naked eye, and catching it would take a telescope driven to follow a point crossing the sky in minutes. What is worth looking at is what it sends back.
Timeline
- Launch
Launched, on the day GCAT records. Source
- Close approach
On Sunday, Nov 8 at 3:02 AM UTC, a fragment of Fengyun 1C (NORAD 31381) was to pass within 299 m of OAO 1 (NORAD 2142). The chance was about 1 in 7,000.
Summary
Over the Pacific Ocean LIVE
Where is OAO 1?
At 4:40:50 PM UTC OAO 1 was over the Pacific Ocean (1.1° S, 143.7° E), 780 km up, moving at 7.46 km/s and in the Earth’s shadow.
What is OAO 1?
A space telescope in low Earth orbit, in space since Apr 8, 1966.
Can I see OAO 1?
No, not with the naked eye: no brightness has been published for OAO 1, and nothing here estimates one; what people use is what it sees, which its operator publishes.
General
- Operator
- NASA Goddard Space Flight Center
- State
- United States of America
- Built by
- Grummann Aerospace Corporation
- What it is
- Space telescope
- Launched
- Mass
- about 1.8 t
- 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
- 4:40 PM UTC
- Station time (UTC)
- 4:40 PM UTC
- Latitude / longitude
- 1.1° S, 143.7° E
- Altitude
- 780 km
- Speed
- 7.46 km/s (26,870 km/h)
- Course
- south-east
- Light
- In the Earth’s shadow until 4:46 PM UTC
- Inclination
- 35°
- Orbital period
- 100.4 minutes
- Orbits per day
- 14.35
- This orbit
- 774 to 784 km
- In shadow
- 35 minutes of each orbit
- In view from
- Within 2,080 km of the point below it
- Elements epoch
- Nov 8, 2026, 5:48 AM, 10 hours old
- Source
- Position from Space-Track orbital elements of Nov 8, 2026, 5:48 AM, 10 hours old.
No operator publishes an ephemeris for OAO 1, so every position here comes from its orbital elements.
In orbit
- Close approaches
- 1 reported. No close approach to OAO 1 is reported for the next three 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
OAO 1 shares its launch, 1966-031, with one other body the catalogue lists in orbit.
| Body | What it is |
|---|---|
| ATLAS AGENA D 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 |
|---|---|---|---|---|
| OAO 1 | 774 to 784 km | 100 minutes | about 1.8 t | 1966 |
| Cheops | 679 to 694 km | 98 minutes | 280 kg | 2019 |
| Fermi | 488 to 498 km | 94 minutes | about 4.3 t | 2008 |
| Hubble | 465 to 480 km | 94 minutes | about 12.2 t | 1990 |
| XMM-Newton | 29,443 to 91,682 km | 2,873 minutes | about 3.8 t | 1999 |
| Chandra | 12,186 to 136,630 km | 3,809 minutes | about 4.8 t | 1999 |
Data and API
The current elements from Space-Track as an OMM object, epoch Nov 8, 2026, 5:48 AM, 10 hours old.
{
"OBJECT_NAME": "OAO 1",
"OBJECT_ID": "1966-031A",
"EPOCH": "2026-11-08T05:48:56.327040",
"MEAN_MOTION": 14.34717246,
"ECCENTRICITY": 0.00069133,
"INCLINATION": 35.0455,
"RA_OF_ASC_NODE": 262.7224,
"ARG_OF_PERICENTER": 341.5486,
"MEAN_ANOMALY": 18.495,
"EPHEMERIS_TYPE": 0,
"CLASSIFICATION_TYPE": "U",
"NORAD_CAT_ID": 2142,
"ELEMENT_SET_NO": 999,
"REV_AT_EPOCH": 17178,
"BSTAR": 0.00004342951,
"MEAN_MOTION_DOT": 0.00000105,
"MEAN_MOTION_DDOT": 0
}