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w 4 | In the News cnrs I international magazine w The Gaia space observatory is scheduled for launch on November 20 aboard a Soyuz rocket from the Kourou-based Space Center in French Guiana. From its vantage point 1.5 million kilometers from Earth, the European Space Agency’s spacecraft will for the first time create a 3D map of 1% of the stars in the Milky Way. Gaia will continuously survey the entire sky for five years, spinning and completing a full turn every six hours. It will analyze the light from each of the billion brightest stars 70 times, with the unrivalled precision of its instruments (two telescopes, a photometric instrument, and a spectrometer). But Gaia will also look beyond our galaxy. It will survey and determine the position of 500,000 quasars, and track down 6000 supernovae in other galaxies. The data will be analyzed by the Data Processing and Analysis Consortium (DPAC), which brings together 400 researchers from 25 countries including France. cnrs makes the headlines i Gigantic Viruses w Huge viruses of about one micron in length—nearly twice the size of the largest discovered so far—were recently identified1 by a team from the IGS2 laboratory. The two microorganisms recently isolated resemble nothing scientists have ever encountered. The team, led by Jean-Michel Claverie and Chantal Abergel, found these microorganisms thousands of kilometers apart. Pandoravirus dulcis was found in Australia, Pandoravirus salinus in Chile. “This suggests they could be widespread across the planet,” says Claverie. w French physicist Alain Aspect won several accolades this year. He was first awarded the 2013 International Balzan Prize by the eponymous Swiss foundation, “for his pioneering experiments which led to a striking confirmation of quantum mechanics as opposed to local hidden-variable theories.” He was later the recipient of the Niels Bohr Medal, especially awarded this year in honor of the 100th anniversary of Niels Bohr’s revolutionary atomic model. Aspect, regarded as an “outstanding and prominent figure in the field of optical and atomic physics,” received the medal at Niels Bohr’s former residence in Copenhagen on October 7, in the presence of Her Majesty the Queen of Denmark. Back in the lab, the team’s microbiology analyses showed that these specimens, like all viruses, contain no ribosomes, do not produce energy, and do not divide. Yet the sequencing of their genetic material led to an astounding discovery: these viruses contain 1900 and 2500 genes respectively. Common viruses have very few genes— a dozen at most. Ten years ago, the discovery of Megaviridae—viruses with more than 1000 genes—already made the headlines. “We thought that was an exception, but we were wrong. This not only questions our conception of how diverse viruses are, but also how they evolved.” Their analysis showed that 93% of the Pandoraviruses’ genes have no known match. “So where do these genes come from?” asks Claverie, keen to state that even distant relationships between lineages are usually found. Not in this case. “They may have derived from a species that expired early on in evolution but whose parasites remained,” he concludes. “We are going to have to rethink what we have been taking for granted.” C. W. 01. N. Philippe et al., “Pandoraviruses: Amoeba Viruses with Genomes Up to 2.5 Mb Reaching That of Parasitic Eukaryotes,” Science, 2013. 341: 281-6. 02. Information génomique et structurale (CNRS / Aix-Marseille Université). Gaia’s Quest to Map the Stars q Artist’s impression of the Gaia spacecraft, with the Milky Way in the background. © J. chatin /CNRS Photothèque Alain Aspect, Niels Bohr Medal © ESA/ATG media lab ; backgr ound image : ESO/S. Brunier


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