GX

Infobox rocket
name = Galaxy Express (GX)
function = Medium expendable Launch vehicle
manufacturer = Galaxy Express (JAXA/ULA/IHI)
country-origin = Japan/United States
height = 48m
diameter = 3.3m
mass = 190,500 kg
alt-mass = 210 tons
stages = 2
LEO-payload = 3,600kg
alt-LEO = 4 tons
payload-location = 800km SSO
payload = 1,814kg
alt-payload = 2 tons
status = In Development
sites = Tanegashima
stage1name = Atlas III
stage1engines = 1 RD-180
stage1thrust = 4,148.7 kN
alt-stage1thrust = 932,670 lb_f
stage1time = 132 seconds
stage1SI = 311 sec
stage1fuel = RP-1/LOX
stage2name = GX
stage2engines = 1 liquid
stage2thrust = 118 kN
stage2time = 480 seconds
stage2SI = 323 sec
stage2fuel = LNG/LOX

The GX expendable launch vehicle is a rocket currently under development by the Galaxy Express Corporation, a joint venture between United Launch Alliance (ULA), IHI Corporation (IHI), the Japan Aerospace Exploration Agency (JAXA), and several other Japanese companies. It will use the boost stage of the Atlas III rocket, provided by ULA, and a newly-designed upper stage made by IHI. The upper stage will be fueled by liquefied natural gas (liquid methane) with liquid oxygen as the oxidizer, making it the only space vehicle to use that combination of fuel and oxidizer.

The GX is intended to compete in the commercial satellite-launch sector. The program began as an effort to upgrade Japan's J-I rocket, which launched only once. Thus, GX was originally known as "JII", albeit briefly. For a time, the program was termed "J1-Upgrade", before finally settling on the current name in January 2003.

JAXA reported that a full-scale second-stage engine had been successfully test-fired in October 2007. JAXA is developing this engine, the responsibility for which would eventually be turned over to the Galaxy Express venture.

In late December 2007, The Yomiuri Shimbun newspaper reported that the GX program was being subjected to a thorough review, mainly because of unexpectedly high additional costs. It also claimed that ULA partner Lockheed Martin had discontinued production of the first stage engine, thereby requiring a redesign, likely costly, to move to another engine. The paper said that the 15 billion yen that JAXA requested for the GX project was eventually slashed to 5.6 billion yen in the Fiscal 2008 budget.

The GX would launch from the Tanegashima Space Center, south of Kyūshū, Japan. Initial launch capability for GX is currently scheduled for 2011.

In May 2008, it was reported that the Space Development Committee, who are overseeing the project, were considering its cancellation. [ [http://www.yomiuri.co.jp/dy/national/20080531TDY03105.htm Daily Yomiuri - Project plagued by problems] ]

References

External links

* [http://www.galaxy-express.co.jp/english/index-e.html GALAXY EXPRESS]
* [http://www.yomiuri.co.jp/dy/features/science/20071224TDY01301.htm Further delay for GX rocket; govt mulls bigger role, Yomiuri Shimbun article, 24 Dec 2007]