TORONTO, May 12, 2015 — We may complain a lot about the weather on earth but perhaps we are much better off here than on some alien worlds, where the daily forecast is cloudy, overcast skies in the morning and scorching heat in the afternoon.
A team of international astronomers including York University scientist Professor Ray Jayawardhana have uncovered evidence of daily weather cycles on six extra-solar planets using sensitive observations from the Kepler space telescope.
“Despite the discovery of thousands of extra-solar planets, what these far-off worlds look like is still shrouded in mystery,” says lead author Lisa Esteves, graduate student at the University of Toronto.
In their paper entitled “Changing Phases of Alien Worlds: Probing Atmospheres of Kepler Planets with High-Precision Photometry” published today in the Astrophysical Journal, the team analyzed all 14 Kepler planets known to exhibit phase variations, and found indications of cloudy mornings on four and hot, clear afternoons on two others.
Most of the worlds examined in the study were very hot and large, with temperatures greater than 1600 degrees Celsius and sizes comparable to Jupiter. These conditions are far from hospitable to life, but excellent for phase measurements, the authors note.
“We are getting to know these exotic alien planets as dynamic, three-dimensional worlds through remote sensing across vast distances. Someday soon we hope to provide similar weather reports for worlds not much bigger than the Earth,” says study co-author Jayawardhana, who adds that upcoming space missions such as TESS (2017) and PLATO (2024) should reveal many small planets around bright stars, making great targets for detailed studies.
For the study, the researchers determined weather on these alien worlds by measuring phase changes as the planets circle their host stars. Similar to the Moon in the solar system, an exoplanet going through a cycle of phases can be traced, from fully lit to completely dark, when different portions of the planet are illuminated by its star.
“The detection of the light from these far-away planets, some of which took thousands of years to reach us, is in itself remarkable,” says co-author Ernst de Mooij of Queen’s University Belfast, UK. “But when we consider that phase cycle variations can be up to 100,000 times fainter than the host star, these detections become truly astonishing.”
The Kepler space telescope was the ideal instrument for the study of exoplanet phase variations, according to the researchers. The telescope’s very precise measurements and the vast amount of data it collected over its initial four-year mission allowed astronomers to beat the noise and measure the tiny signals from these distant worlds.
York University is helping to shape the global thinkers and thinking that will define tomorrow. York U’s unwavering commitment to excellence reflects a rich diversity of perspectives and a strong sense of social responsibility that sets us apart. A York U degree empowers graduates to thrive in the world and achieve their life goals through a rigorous academic foundation balanced by real-world experiential education. As a globally recognized research centre. York U is fully engaged in the critical discussions that lead to innovative solutions to the most pressing local and global social challenges. York U’s 11 faculties and 25 research centres are thinking bigger, broader and more globally, partnering with 280 leading universities worldwide. York U’s community is strong − 55,000 students, 7,000 faculty and staff, and more than 275,000 alumni.
Gloria Suhasini, York University Media Relations, 416 736 2100 ext. 22094, email@example.com
Sean Bettam, Communications Officer, Faculty of Arts & Science, University of Toronto, 416 946 7950, firstname.lastname@example.org