The pair were honoured for “their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation,” the jury said.
Under the Big Bang theory, the cosmos was formed from a cataclysmic explosion that happened about 13.7 billion years ago.
The timescale and geometry are measurable by shockwaves called cosmic microwave background (CMB) that continues to wash over us.
Mather, 60, is a senior astrophysicist at NASA’s Goddard Space Flight Center in Maryland, while Smoot, 61, is a professor of physics at the University of California at Berkeley.
Mather and Smoot worked on the COBE satellite launched by NASA in 1989, whose results provided increased support for the Big Bang scenario, as this is the only scenario that predicts the kind of cosmic microwave background radiation measured by COBE.
“These measurements also marked the inception of cosmology as a precise science,” the Nobel jury said.
Mather coordinated the entire process and had responsibility for the experiment that revealed the blackbody form of the microwave background radiation measured by COBE.
Smoot meanwhile had the main responsibility for measuring the small variations in the temperature of the radiation.
Last year, the Physic Prize went to Americans Roy Glauber and John Hall and German Theodor Haensch for groundbreaking work on understanding light and optics.
The 2006 laureates will each receive a gold medal and a diploma and will share a cheque for 10 million Swedish kronor at the formal prize ceremony held, as tradition dictates, on December 10th, the anniversary of the death in 1896 of the prize’s creator Alfred Nobel.
The Nobel prizes, founded by Swedish industrialist Alfred Nobel, the inventor of dynamite, were first awarded in 1901.
On Monday, the Nobel Medicine Prize went to US research duo Andrew Fire and Craig Mello for their discovery of how to silence malfunctioning genes, a breakthrough which could lead to an era of new therapies to reverse crippling disease.
The Chemistry Prize will be announced on Wednesday. The Economics Prize is scheduled for Monday, October 9, and the Peace Prize on Friday, October 13.
The date for the Literature Prize has yet to be announced but it is traditionally on a Thursday, and could fall on October 5 or October 12.