Voyager 2 concludes encounter with Neptune, provides wealth of new

Sep 4, 1989 - Voyager's 12 scientific instruments are providing planetary scientists with a wealth of new data on this previously mysterious planet an...
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Delta rocket lifts off, taking U.K. broadcasting satellite into orbit ministration, or by governmentowned or -subsidized companies, such as the European consortium whose Ariane rocket now dominates launching of commercial satellites. "We're now aggressively entering the world competition to launch satellites, " stresses Stephanie LeeMiller, director of DOT's Office of Commercial Space Transportation (OCST), which regulates U.S. commercial launch activities. U.S. efforts to encourage commercial launch

services accelerated after the Challenger disaster of January 1986 grounded the space shuttle for 32 months. The Reagan Administration ordered most commercial payloads off the shuttle, and in early 1988 issued a Presidential Directive promoting private sector investment in space. A further initiative in this area is expected from the Bush Administration this fall. Last week's landmark flight is the second commercial launch licensed by OCST. The first was a suborbital launch in March of a two-stage rocket built by Space Services Inc. of America (SSI), which carried a Consort 1 payload for the University of Alabama in Huntsville's Consortium for Materials Development in Space. This 15-minute flight provided about seven minutes of weightlessness for six experiments, including study of microgravity's effects on demixing of immiscible polymers, elastomer-modified epoxy resins, organic foam processing, powdered metal sintering and infiltration, surface coatings and catalyst production by electrodeposition, and materials dispersion in a new device. An OCST manifest issued in June lists five more commercial space launches licensed for 1989 and 27 through mid-1993. A new manifest later this m o n t h will add more flights. Seven U.S. firms, with a total investment of more than $500 million, now sell launch services.

The manifest lists 21 orbital launches by three major firms: McDonnell Douglas (8), General Dynamics (8), and Martin Marietta (5). It also lists six suborbital flights for microgravity research by three smaller firms: SSI (2), Space Data Corp. (2), and American Rocket Co. (2). SSI, for example, will launch a Consort 2 payload this November with experiments for the Alabama consortium and three other NASAsupported centers. And Space Data will launch Joust 1 and 2 payloads in the summers of 1990 and 1991, p r o v i d i n g 12 to 15 m i n u t e s of weightlessness. Richard Seltzer

Benzene emissions ordered cut by 90% Last week, the Environmental Protection Agency ordered a 90% reduction of industrial benzene emissions over the next several years. The cost to industry in general is estimated at $1 billion, but is likely negligible for chemical producers. The order represents the agency's first attempt at regulating a toxic air pollutant under guidelines set by a federal district court in 1987 in a case involving vinyl chloride. That ruling required EPA to use a two-step process in setting air standards. First, EPA must determine a

Voyager 2 concludes encounter with Neptune, provides wealth of new data Voyager 2 last week completed what mission scientists are calling a nearly flawless encounter with the planet Neptune, shown here from a distance of about 12 million km. Voyager's 12 scientific instruments are providing planetary scientists with a wealth of new data on this previously mysterious planet and its moons and rings. Visible in this image is Neptune's "great dark spot" (left), an atmospheric feature very likely similar to Jupiter's great red spot. Cirruslike clouds of methane ice (white streaks) apparently form high in the atmosphere above the spot, but do not circulate around it, which has made it difficult for mission scientists to determine the direction and velocity of winds around the spot. Voyager scientists speculate that methane plays an important role in Neptune's predominantly hydrogen and helium atmosphere, forming clouds in the troposphere and being converted by sunlight in the stratosphere into a smog of ethane and acetylene ices.

September 4, 1989 C&EN

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