WMAP is no more ...

Quietly, and almost unnoticeably (though check this New York Times editorial), Wilkinson Microwave Anisotropy Probe has lived up its science days. First on Aug, 19, 2010, the satellite  stopped taking scientific data, and then on Oct, 09, 2010 left its anchor point at Sun-Earth Lagrange 2 (L2) point, which it was orbiting around since 2001, to join a stable orbit around the Sun. The satellite's mission has been therefore concluded. Its thrusters will ignite no more ...


In the community WMAP, as it is commonly referred to, has come to be known for many things. First, for its impressive fast track implementation, which started with the proposal in 1995, went on to its launch in 2001, and then the first release of the scientific data in 2003 (compare that with the timeline of European Planck mission - the WMAP successor: first proposal in 1995, launch - 2009, observing as we speak), for its impact on precision cosmology, and for its success in securing multiple extensions, which have finally seen the mission to operate over 9 year period until the very now. But also as a mission, which scooped by small scale balloon-borne and ground-based experiments to the multiple discoveries, (just recall: the first acoustic peak - Boomerang and MAXIMA; the secondary peaks - Boomerang and DASI;   the CMB E-polarization - DASI and Boomerang) had to redefine itself again and again, finally, and successfully, emerging as a quintessential, precision experiment. And indeed the impact of  WMAP on the precision aspects of cosmology is difficult to overestimate. Eitheir on its own or in a combination with other cosmological and/or astrophysical data  WMAP has grown to be an indisputable bearer of the cosmological golden standards at this time - a fact well illustrated by the 'official' top ten list of its highlights,, which though missing on the discoveries is by far very impressive. 

The legacy of WMAP is multifaceted and goes beyond what mentioned above. It includes, for example, a highly successful CMB data repository, Lambda, and a trove of high quality and visually attractive images, used nowadays in nearly every cosmology talk worldwide.  Not to mention of course the CMB beach balls loitering lazily in so many of our offices. And with all its success and efficiency, WMAP has been a testament to strengths and capabilities of a small team, sharing a nearly 100% commitment and dedication, recall Shelley's 'singleness of the mind' - this time a team mind though, to team goals, again somewhat counter the trends in present day cosmology/astrophysics. (For two interesting views of how the astronomy 'could/should/may have to' be done, check here and here.)

And then we should not forget that it also brought two Nobel Prizes in physics in 2006, including our very own George Smoot, by corroborating the COBE-DMR maps of large scales CMB anisotropy.

Operational, the satellite is no more, the results however will keep on coming for some time to come. If only because the two last years of the mission have not been yet analyzed. The attention of the community is however already shifting towards the next step, the Planck mission. For Planck this has been a symbolic moment, like a cosmological relay baton passing from its very successful predecessor. And the time, and work of the very many Planck researchers, will only show if it lives up to the solemnity of this moment.