This year's Nobel prize in physics was announced! The prize was split between two different ways of studying our Universe.

James Peebles was awarded half of the price for his theoretical work in
physical cosmology. His ground-breaking work focused on the earliest stages of our Universe; for example, the cosmic microwave background – which is among the most valuable probes into the primordial eras.

This radiation was formed only a couple of thousands of years after the Big Bang when it decoupled from freshly formed neutral matter. Then it
aged – and stretched – with The Universe, now having temperature only 2.7˚C above the absolute zero. It is coming from every direction and there are mild (but measurable) deviations that carry valuable information about the structure of our Universe.

Peebles also contributed to areas of research of dark matter and energy,
the Big Bang nucleosynthesis and formation of large-scale structures such as galaxies.

Michel Mayor and Didier Queloz split the other half of the award for the
discovery of an exoplanet orbiting solar-type stars. Exoplanets are planets orbiting stars other than our Sun. They were believed to exist but hard to capture, as contrary to stars, the do not shine.

Indirect methods of exoplanet observations focus on their effect on their host star. For example, if the planet is very massive, the stare is forced to move as they together revolve around a common centre of mass. This movement can be detected as it causes a slight shift in the light radiation from the star. Its wavelength shortens (turns slightly bluer) as the star is moving towards as and extends (turns slightly redder) as it is moving away from us.

This method was used to discover 51 Pegasi b, which was announced in the
year 1995. It is located approximately 50 light-years from Earth, weighs
half as Jupiter and is around 1000 ˚C hot.

The field of exoplanet is very active, today we know of more than 4000
exoplanets, vigorously looking for a sign of life in their atmospheres.

*DIAS contributes to research in both of these areas
(https://www.dias.ie/2019/03/27/gravity-instrument-breaks-new-ground-in-exoplanet-imaging/
<https://www.dias.ie/2019/03/27/gravity-instrument-breaks-new-ground-in-exoplanet-imaging/>*

*https://arxiv.org/pdf/0806.2458.pdf
<https://arxiv.org/pdf/0806.2458.pdf>