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<jats:p> <jats:bold>SAN FRANCISCO</jats:bold> —For eons, pieces of Earth's ocean floor have vanished like the lost continent of Atlantis, sinking below the surface as part of the plate-tectonic cycle. Now, seismic images reveal that these slabs plummet deep into the Earth; the new work may end a long-running debate by showing that the slabs mix the Earth's mantle from top to bottom. </jats:p>

<jats:p>At the bottom of Earth's mantle lies a strange realm, where “continents” may fall from above, fiery bogs stew above the molten core, and whole chunks of landscape can loft upward like so many hot-air balloons.</jats:p>

<jats:p>At the influential 4th Conference on Retroviruses and Opportunistic Infections last week, researchers praised the potent new drugs that can pound the AIDS virus so hard that even the most sensitive tests cannot detect it in the blood of HIV-infected people. But studies reported at the meeting also highlighted an important caveat about the new drugs: They have yet to cure anyone of HIV infection—and it's not yet clear whether they ever will.</jats:p>

<jats:p>A group at the University of Colorado and the National Institute of Standards and Technology in Boulder has serendipitously created two Bose-Einstein condensates—each one a crowd of atoms in a single quantum state—in a supercooled magnetic trap. Their cooling technique worked directly on only one of the condensates, but the other one cooled “sympathetically,” which suggests that the strategy could be used to condense</jats:p>

<jats:p> The word laser has taken on a new meaning: a beam of atoms marching in quantum lockstep, like the photons of a light laser. Two years ago, physicists achieved the crucial starting point for an atom laser, which could aid everything from atomic clocks to chipmaking, when they created an exotic brew of atoms all merged in a single quantum state. Now, a group at the Massachusetts Institute of Technology reports in this issue ( <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="p. 637" related-article-type="in-this-issue" vol="275" xlink:href="10.1126/science.275.5300.637" xlink:type="simple">p. 637</jats:related-article> ) that they have shaped this “Bose-Einstein condensate” into pulses, each one a single, coherent “matter wave.” </jats:p>

<jats:p> Two years ago, biologists thought they had identified a master control gene for eyes, a gene called <jats:italic>eyeless</jats:italic> that apparently could single-handedly cause surplus eyes to sprout from wings and antennae of fruit flies. Now a new gene, <jats:italic>dachshund</jats:italic> , appears to work in tandem with <jats:italic>eyeless</jats:italic> —suggesting that the “master controller” may merely be a member of a committee instead. </jats:p>

<jats:p> <jats:bold>TORONTO</jats:bold> —Astronomers had thought that the high-speed clouds of hydrogen atoms that roam through space are accelerated by supernova explosions within our galaxy. But a new proposal argues that they may be something much grander: huge, distant remnants of the galaxy's formation that extend well beyond the Milky Way and could fuel the formation of new stars for billions of years into the future. </jats:p>

<jats:p> <jats:bold>TOKYO</jats:bold> —A new Japanese satellite, scheduled for launch on 7 February, should give radio astronomers a much better look at black holes and other extremely energetic objects in the universe. A successful mission is also expected to boost the fortunes of one of the country's premier research institutes as it seeks a larger role in Japan's exploration of space. </jats:p>

<jats:p> Because the eye disease glaucoma develops so insidiously, it blinds almost 12,000 people every year in the United States alone. Now, researchers report in this issue ( <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="668" related-article-type="in-this-issue" vol="275" xlink:href="10.1126/science.275.5300.668" xlink:type="simple">p. 668</jats:related-article> ) that they have identified the gene at fault in juvenile glaucoma—the first time a specific gene has been linked to the condition. The discovery may aid in the diagnosis of glaucoma and provide clues to how it causes a buildup of pressure in the eye, which is thought to lead to blindness by irreversibly damaging the optic nerve. </jats:p>