| 词条 | EchoStar IV |
| 释义 |
| name = EchoStar IV | image = | image_caption = | mission_type = Communications | operator = EchoStar | website = | COSPAR_ID = 1998-028A | SATCAT = 25331 | mission_duration = 12 years | spacecraft_bus = A2100AX | spacecraft_type = | manufacturer = Lockheed Martin | dry_mass = {{convert|1,400|kg|lb|abbr=on}} | launch_mass = {{convert|3,478|kg|lb|abbr=on}} | BOL_mass = | dimensions = | power = 10 kW | launch_date = {{start-date|May 7, 1998, 23:45|timezone=yes}} UTC | launch_rocket = Proton-K/Blok-DM3 | launch_site = Baikonur 81/23 | launch_contractor = | disposal_type = | deactivated = {{end date|July 2011}} | orbit_epoch = May 14, 2017[1] | orbit_reference = Geocentric | orbit_regime = Geostationary | orbit_periapsis = {{convert|36,085.2|km|mi|sp=us}}[1] | orbit_apoapsis = {{convert|36,250.7|km|mi|sp=us}}[1] | orbit_inclination = 7.0 degrees[1] | orbit_semimajor = {{convert|42,538.0|km|mi|sp=us}}[1] | orbit_period = 1,455.3 minutes[1] | orbit_longitude = 77° west[1] | apsis = gee | trans_band = 32 {{Ku band}} | trans_frequency = Uplink: 17.3 - 17.8 GHz Downlink: 12.2 - 12.7 GHz | trans_bandwidth = 24 MHz | trans_capacity = | trans_coverage = United States, Mexico and Puerto Rico | trans_TWTA = | trans_EIRP = 53 dBW | trans_HPBW = }} EchoStar IV is a communications satellite operated by EchoStar. Launched in 1998 it was operated in geostationary orbit at a longitude of 77 degrees west for 12 years. SatelliteThe launch of EchoStar IV made use of a Proton rocket flying from Site 81 at the Baikonur Cosmodrome, Kazakhstan. The launch took place at 23:45 UTC on May 7, 1998, with the spacecraft entering a geosynchronous transfer orbit. EchoStar IV carried 32 Ku band transponders to provide direct voice and video communications to small dishes in North America after parking over 119° W or 148° W longitude.[2] Specifications
See also{{Portal|Spaceflight}}
References1. ^1 2 3 4 5 6 {{cite web|url=https://www.n2yo.com/satellite/?s=25331/ |last=N2yo |title=ECHOSTAR 4 |accessdate=November 28, 2017}} {{Orbital launches in 1998}}{{EchoStar satellites}}{{US-spacecraft-stub}}2. ^{{cite web|url=http://www.satbeams.com/satellites?id=25331|title=EchoStar 4|publisher=SatBeams|accessdate=September 28, 2017}} 6 : Spacecraft launched in 1998|Communications satellites in geostationary orbit|Satellites using the A2100 bus|Spacecraft launched by Proton rockets|Derelict satellites orbiting Earth|EchoStar satellites |
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