If a ghost hunt ever occurred in space, it would be the search for dark matter, spatial objects that have mass but cannot be seen.

According to the Associated Press, an international team of scientists believe they are on to solving the perplexing objects despite another attempt that came up empty.

Using the most sensitive dark matter detector, the Large Underground Xenon (LUX) experiment, physicists on the project are optimistic. The detector has not found anything in thus far, and neither has one attached to the International Space Station (ISS), but the device is twice as sensitive as the next best one.

Only a number of months into the project, the researchers released their first progress report Wednesday. They are currently working in an abandoned goldmine in Lead, S.D., the Stanford Underground Research Facility.

"This is only the beginning for LUX," Dan McKinsey of Yale University, co-spokesperson for LUX, said in a press release. "Now that we understand the instrument and its backgrounds, we will continue to take data, testing for more and more elusive candidates for dark matter."

Nearly 5,000 feet below the surface, the researchers hope to have any background radiation eliminated. They attempted to trap dark matter, hoping it would show itself as weakly interacting massive particles (WIMPs), and see its light fingerprint bouncing off an atomic nucleus of xenon cooled off to negative 150 degrees Fahrenheit.

According to the New York Times, the experiment will run for another year and will end with LUX getting a sensitivity upgrade.

"Just because we don't see anything in the first run doesn't mean we won't see anything in the second," said Richard Gaitskell, co-spokesperson and Brown University physicist.

Astronomers and other experts believe dark matter makes up one quarter of the universe and vast space it resides in. Much like the cosmos (and ghosts), it is mysterious and not visible, but some believe it has mass and does exist.

Neal Weiner, a particle theorist at New York University, was impressed by the team's non-findings.

"They have not found dark matter," he said. "There is nothing smacking you in the face to make you think there is something there." But as the sensitivity of the detector increases, he added, "If there is anything in there, it should become apparent."

Juan I. Collar, a dark matter specialist at the University of Chicago, speculated that the detector's calibration needed to be just right to find dark matter. Nonetheless, he is part of the scientific community who believes LUX will succeed.

"They do have a real interest in performing those calibrations, because they would settle the issue," Dr. Collar said in an email. "We just have to be patient. At the end they promised to do so, and I have no doubts they will."