Where Is The Xenon

I just can't resist a noble gas story:

The missing-xenon paradox is one of science’s great whodunits. Researchers have hypothesized that the element is lurking in glaciers, minerals or Earth’s core, among other places.
“Scientists always said the xenon is not really missing. It’s not in the atmosphere, but it’s hiding somewhere,” says inspector, sorry, professor Hans Keppler, a geophysicist at the University of Bayreuth in Germany. He and his colleague Svyatoslav Shcheka are the latest geoscientists to tackle the case, in a report published today in Nature.
They went looking for answers in minerals. Magnesium silicate perovskite is the major component of Earth’s lower mantle — the layer of molten rock between the crust and the core, which accounts for half the planet’s mass. The sleuthing scientists wondered whether the missing xenon could be squirreled away in pockets in this mineral. “I was quite sure that it must be possible to stuff noble gases into perovskite,” says Keppler. “I suspected xenon may be in there.”
The researchers tried dissolving xenon and argon in perovskite at temperatures exceeding 1,600 ºC and pressures about 250 times those at sea level. Under these extreme conditions — similar to those in the lower mantle — the mineral sopped up argon yet found little room for xenon.
Those results may sound disappointing, but they gave Keppler and Shcheka an idea. What if xenon isn’t hiding at all?
More than 4 billion years ago, Earth was molten. Meteorites bombarded the planet, causing it to lose much of its primordial atmosphere. Keppler and Shcheka suggest that argon and the other noble gases hid in perovskite, but most of the xenon could not dissolve in the mineral, and disappeared into space.

I didn't realize the Xenon was missing.  If neon wasn't such an attention hog, maybe I'd have noticed.