NASA eyes purchasing Japan's HTV spacecraft

Space Weather News for July 22, 2008
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DESCENDING SPACE JUNK: Almost exactly one year ago, on July 23, 2007, International Space Station astronauts threw an obsolete, refrigerator-sized ammonia reservoir overboard. The 1400-lb piece of space junk has been circling Earth ever since and now, in July 2008, its orbit has decayed so much that it has become an easy naked-eye target for backyard sky watchers. The "Early Ammonia Servicer" (EAS for short) is almost as bright as the stars of the Big Dipper and growing brighter as it descends. Today's edition of http://spaceweather.com displays photos of the EAS, which is expected to burn up in Earth's atmosphere in late 2008 or early 2009. Readers who wish to see the EAS with their own eyes should check the Simple Satellite Tracker for flyby times: http://spaceweather.com/flybys. Europeans are favored with flybys this week, North Americans next week.

The Yomiuri Shimbun

The U.S. National Aeronautics and Space Administration has begun unofficial negotiations with the Japan Aerospace Exploration Agency on purchasing units of the H-2 Transfer Vehicle (HTV), an unmanned cargo transfer spacecraft developed in Japan, as the successor to its space shuttles, which are to retire in 2010, The Yomiuri Shimbun learned Saturday.

Behind the move is NASA's concern that the retirement of its space shuttles will make it difficult for the United States to fulfill its responsibilities to deliver water, food and materials for scientific experiments to the International Space Station.

Japan has never sold such an expensive, domestically developed item of space hardware as the 14 billion yen HTV to other countries. If a contract is concluded, it will be the biggest in the country's 50-year space development history.

The HTV is being developed by JAXA, Mitsubishi Heavy Industries, Ltd., Mitsubishi Electric Corp. and others. The cylindrical cargo spacecraft, measuring 10 meters in length and 4.4 meters in diameter, is capable of carrying a maximum of six tons of cargo. It will be launched on an H-2B vehicle, which is currently under development, and separated in space to dock with the ISS.

Japan, European nations, Russia and the United States share responsibilities for the delivery of necessary items to the ISS, where astronauts stay for long periods to carry out scientific experiments

Currently, active cargo-transfer spacecraft are the space shuttle of the United States, Russia's Soyuz, both manned, and Russia's unmanned Progress and Europe's unmanned Automated Transfer Vehicle (ATV).

Japan's HTV will be introduced next autumn, and the spacecraft will be launched at the rate of one per year.

NASA will retire the space shuttles because they are costly to operate, and they have safety concerns. However, the United States will not be able to begin operating a successor to the space shuttle it will build until 2018 at the earliest.

So to bridge the gap between the space shuttles and their successors, the United States is considering purchasing the HTV.

In April, NASA started a project to assist U.S. companies' development of a spacecraft to succeed the space shuttle.

However, it is uncertain whether it will be possible for the successor vehicle to be developed in the two years left before the space shuttle is to be scrapped, prompting NASA to discuss buying foreign spacecraft.

The U.S. Congress has a psychological resistance to buying Russian spacecraft, and the ATV's transport capacity is smaller than that of the HTV. NASA, therefore, is considering ordering HTVs.

JAXA said it has been unofficially discussing the matter with NASA since February.
(Jul. 20, 2008)