Indian footprint in universe's map

The best and finest map of the universe – released by the European Space Agency on Thursday – may not have been possible without key contribution from a bunch of Indian astrophysicists in Pune.

The reconstructed image of the early universe is based on what is known as cosmic microwave background – the relic radiation from the Big Bang – using data collected by ESA’s Planck space telescope.

The map discloses interesting new features that challenge the foundation of current human understanding of the universe. Because of its high precision, Planck’s map found some peculiar unexplained features that may well require new physics to be understood.
But these oddities would not have been seen without the contribution made by Sanjit Mitra, a scientist at Inter-University Centre for Astronomy and Astrophysics in Pune who corrected “beam distortion” so that better images can be seen.

“My task was correction of images captured by the Planck for reconstructing the first light map of the universe. Planck space probe produces sky maps in nine frequencies, each having a CMBR and a foreground. Our challenge was to remove the foreground and recreate the cosmic microwave background as it was,” Mitra told Deccan Herald.

Mitra was associated with the work since 2008 when he was working at Jet Propulsion Laboratory in the USA. He returned to IUCAA in 2011 and continued the work.

Two other IUCAA scientists, Tarun Souradeep and Aditya Rotti, were also part of a core team involved in analysing the new CMBR map.

“The new map is three times better and five times more sensitive than WMAP. Planck images are more reliable,” said Souradeep. Just after the Big Bang 13.7 billion years ago, the young universe was filled with a hot dense soup of interacting protons, electrons and photons at about 2,700 degrees Celsius.

When the protons and electrons joined to form hydrogen atoms, the light was set free. As the universe expanded, that light stretched out to microwave wavelengths, equivalent to a temperature of just 2.7 degrees above absolute zero (minus 273 degrees Celsius).
This cosmic microwave background – CMB – shows tiny temperature fluctuations that correspond to regions of slightly different densities at very early times, representing the seeds of all future structure: the stars and galaxies.

“This image shows the universe has more odds than previously thought. It sheds new light on dark matter and dark energy. New physics is required to explain some of the features of the universe observed by the Planck,” explained Souradeep.
The image is based on the initial 15.5 months of data from Planck and is the mission’s first all-sky picture of the oldest light in our universe, imprinted on the sky when it was just 3,80,000 years old.

Compared to the images captured by its predecessors – two space probes known as COBE and WMAP – Planck images depict the universe in sharper focus enabling scientists to find out new cosmic phenomenon, which was not possible earlier. This is the first release of results from Planck. The next major release that will include the full data set and further refinement in the analyses is expected in 2014.

“The extraordinary quality of Planck’s portrait of the infant universe allows us to peel back its layers to the very foundations, revealing that our blueprint of the cosmos is far from complete,” says Jean-Jacques Dordain, ESA’s director general.

Mapping


*Cosmic microwave background: detected in 1964
*First space probe: Cosmic Microwave Explorer launched in 1989
*COBE found first evidence of CMBR in 1992
*Second probe Wilkinson Microwave Anisotropy Probe launched in 2001
*WMAP reconfirms COBE results with more precision
*WMAP data being released nine times between 2003 and 2012
*Third probe Planck launched in 2009
*Planck gives even more precise picture of the Universe