Monday 28 July 2014

Hot Exoplanets Challenge Planet-Formation Theories

An artist's impression of hot Jupiter HD 188753. Image courtesy of Yves LC, Wikipedia.




Joel Kontinen

Naturalistic planet-formation theories are in crisis. The more astronomers get to know about exoplanets or planets outside our solar system, the more obvious it becomes that ours is a very privileged system, fine-tuned for life.

A recent paper based on measurements from the Hubble Space Telescope and published in Astrophysical Journal Letters suggests that previous theories are wrong.

According to Nature news, the research “re-analyses observations of the exoplanets HD 189733b, HD 209458b and WASP-12b, which are 20–270 parsecs (60–870 light years) away from Earth. As each exoplanet crossed in front of its host star, Hubble observed the spectrum of infrared light filtering through the planet’s atmosphere. A team led by Nikku Madhusudhan, an astronomer at the University of Cambridge, UK, then used atmospheric models to determine the combination of elements that produced each planet’s spectrum.

The results suggest that the environments of all three hot Jupiters are drier than Jupiter itself. HD 209458b, which yielded the most precise measurements, seems to be the driest — its atmosphere is 1,000 times drier than Jupiter's, and 100 times drier than the Sun's.”

Astronomers believe that planets “ should accumulate molecules such as water faster than their host stars, write the authors. Hot Jupiters typically form in water-rich areas of solar systems and migrate toward their host stars.”

It seems that they will have to give up their theory and think of something else.

In any case, the research suggests that our system is special. Unfortunately, this is something that some scientists are unwilling to accept, as it means that our system is fine-tuned for life, just like the Book of Genesis indicates.

Source:

Zastrow, Mark. 2014. 'Hot Jupiter' measurements throw water on theory. Nature news (24 July).