USA 23 (18009)

COSPAR: 1987-043E | Alt Name: USA-23

Image

Additional Sources

Launch Details

Launch Date

May 15, 1987

Launch Site

AFWTR

Launch Pad

SLC3E

Launch Vehicle

Atlas H

Orbital Elements

NORAD ID

18009

International Designator

1987-043E

Epoch

Fri, 03 Jul 2026 18:35:39 GMT

Apogee

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Perigee

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Inclination

63.30°

Right Ascension

311.08°

Eccentricity

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Argument of Perigee

105.63°

Period

103.76 min

Mean Motion

13.88 rev/day

Latitude

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Longitude

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Altitude

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Velocity

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Polar Plot

3D Visualization

Basic Satellite Info

Name

USA 23

Alternative Name

USA-23

Type

Payload

Status

Unknown

Owner

NRO/NRL

Country

United States

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs

1 18009U 87043E   26184.77476593  .00012118  00000-0  71757-3 0  9992

2 18009  63.2957 311.0801 0779770 105.6329 263.2100 13.87764145347799

Source: Celestrak

Summary

USA 23, also known as USA-23, is an ocean surveillance and ELINT satellite launched by the US on May 15, 1987, from AFWTR SLC3E using an Atlas H launch vehicle. The spacecraft, identified as NORAD CAT ID 18009 and OBJECT ID 1987-043E, is part of the NOSS SSU series manufactured by MM for NRO/NRL. It has a gravity gradient stabilized configuration and carries the PARCAE 9 SSU-1 payload. The satellite measures 0.9 meters in length with a diameter of 0.4 meters and spans 10 meters when fully deployed. At launch, it had a mass of 200 kilograms and its dry mass remains at this value. It is powered by four deployable solar arrays along with batteries for energy storage. The specific equipment and motor details are not provided.

Physical Characteristics

Length

0.9

Diameter

0.4

Span

Dry Mass

200

Launch Mass

200

Shape

Box + Ant

Radar Cross Section

Unknown

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

PARCAE 9 SSU-1

Purpose

Ocean Surveillance, ELINT

Mission

Ocean Surveillance, ELINT

Manufacturer

Life Expectancy

Unknown

Bus

NOSS SSU

Configuration

Gravity gradient stabilized

Motor

Equipment

Power System

4 deployable solar arrays, batteries

ADCS

Unknown

Transmitter Frequency

Unknown

Map

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Latitude

Longitude

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Azimuth Elevation Time (Local)

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