The SWAS team has already devised a scenario to explain the low water counts, concluding that more water is frozen onto dust grains than anticipated.
There are no observational signs of frozen oxygen, so there is no easy out available to us," says Cornell astronomer Paul Goldsmith, a SWAS team member.
Further investigation by SWAS, and future experiments on other spacecraft, could help us understand where oceans come from, says Melnick.
Exactly how the water in Earth's oceans got here is still "the weakest link in our theory," according to Cornell astronomer Martin Harwit, a member of both the ISO and SWAS science teams.
By extending their survey to a couple hundred regions scattered throughout the galaxy, SWAS astronomers hope to gain a better grasp of the water-abundance measurements and test the theory that water is frozen on grains,.
Pending the conclusions later this month of a NASA review board investigating the latest Pegasus failure, as well as the recommendations of another panel charged with reviewing the agency's policy on testing new launch vehicles, SWAS
could suffer an additional delay of up to 21 months.
The utility of a SWASS antenna would be maximised if the slots operate across the entire bandwidth that is available in the waveguide.
One way to integrate the spiral antenna into the SWASS concept is to cut spiral slots on the broad wall of rectangular waveguides where spiral slots are part of a SWA array.
This slot shape covers almost the entire X-band and can be easily integrated into SWASS panels as an element of an array.
Previous SWASS development has been conducted on CFRP waveguides with the same internal cross-section [7-9].