Mission typeCommunication
OperatorSKY Perfect JSAT Group
COSPAR ID1996-007A [1]
SATCAT no.23781
Mission duration10 years (planned)
Spacecraft properties
SpacecraftN-STAR b
BusSSL 1300
ManufacturerSpace Systems/Loral
Launch mass3,400 kg (7,500 lb) [2]
BOL mass2,050 kg (4,520 lb)
Dry mass1,617 kg (3,565 lb)
Start of mission
Launch date5 February 1996, 07:19:38 UTC[1]
RocketAriane 44P H10-3
Launch siteCentre Spatial Guyanais, ELA-2
Orbital parameters
Reference systemGeocentric orbit
RegimeGeostationary orbit
Band6 C-band
11 Ka-band
8 Ku-band
1 S-band[3]
Coverage areaJapan

N-STAR b, was a geostationary communications satellite originally ordered by a consortium including NTT DoCoMo and JSAT Corporation, and later fully acquired by JSAT, which was merged into SKY Perfect JSAT Group. It was designed and manufactured by Space Systems/Loral on the SSL 1300 platform.[2] It had a launch weight of 3,400 kg (7,500 lb), and a 10-year design life.[2] Its payload is composed of 6 C-band, 11 Ka-band, 8 Ku-band and 1 S-band transponders.


N-Star was created as a joint venture between JSAT, Nippon Telegraph and Telephone (NTT), NTT Communications and NTT DoCoMo for the supply of these latter two WIDESTAR satellite telephone and data packet service.[4] JSAT would handle the satellite side of business and NTT DoCoMo would operate the payload.[5][6]

Two identical satellites were ordered on 1992 from Space Systems Loral, N-STAR a and N-STAR b, for 1995 and 1996 on orbit delivery.[7][8] They would be "switchboards in the sky" having S-band, C-band, Ka-band and Ku-band payload.[9]

N-STAR a was successfully launched aboard an Ariane 44P on 29 August 1995. Its twin, N-STAR b, launched on 5 February 1996, also aboard an Ariane 44P.[2][9] The satellite telephone service was operational in March 1996. In March 2000, the packet communications service was introduced.[10] In March 2000, JSAT received the NTT Communications interest in the N-STAR a and N-STAR b.[11][12]

In August 2003, the JSAT acquired the NTT DoCoMo interest on N-STAR a and N-STAR b, whom then leased them back.[13][14]

See also


  1. ^ a b "Display: N-STAR B 1996-006A". NASA. 10 February 2021. Retrieved 18 March 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ a b c d Krebs, Gunter (11 December 2017). "N-Star a, b". Gunter's Space Page. Retrieved 18 March 2021.
  3. ^ "Communications in Japan 1999" (PDF). General Planning and Policy Division, Minister's Secretariat (page 132) (Whitepaper). Communications in Japan (1999 ed.). Ministry of Posts and Telecommunications of Japan. Retrieved 18 March 2021.
  4. ^ "FORM 20-F/A AMENDMENT NO.1 TO FORM 20-F" (PDF). NTT DoCoMo. 8 February 2002. Retrieved 2 August 2016.
  5. ^ "FORM 20-F/A AMENDMENT NO.1 TO FORM 20-F" (PDF). NTT DoCoMo. 10 July 2002. Retrieved 2 August 2016.
  6. ^ "FORM 20-F/A AMENDMENT NO.1 TO FORM 20-F" (PDF). NTT DoCoMo. 8 February 2002. pp. 33–34. Retrieved 18 March 2021.
  7. ^ "N-Star". Global Security. Retrieved 2 August 2016.
  8. ^ "Awards & Launch History - 1300 Bus Satellites". SSL (company). Archived from the original on 12 August 2015. Retrieved 20 August 2016.
  9. ^ a b "N-Star a and b". SSL (company). Retrieved 18 August 2016.
  10. ^ Yamamoto, Kazuichi; Furukawa, Makoto; Satoh, Hijin; Nishi, Yasuki; Kouji, Horikawa (September 2010). "Overview of WIDESTAR II Mobile Satellite Communications System and Service" (PDF). NTT DoCoMo Technical Journal. NTT DoCoMo. 12 (2): 37–42. Retrieved 2 August 2016.
  11. ^ "Who we are?". SKY Perfect JSAT Group. 3 August 2012. Retrieved 2 August 2016.
  12. ^ "History". SKY Perfect JSAT Holdings Inc. Retrieved 18 March 2021.
  13. ^ "NTT DoCoMo to Transfer Satellite Assets to JSAT and Acquire JSAT Common Stock". NTT DoCoMo. 31 July 2003. Retrieved 2 August 2016.
  14. ^ "FORM 20-F/A AMENDMENT NO.1 TO FORM 20-F" (PDF). NTT DoCoMo. 28 June 2004. Retrieved 2 August 2016.