Even with about 2,000 confirmed planets found outside the solar system, we know so little about them. What are they made of? Are their atmospheres habitable? What weather exists?
It will take a whole new generation of "big-eyed" telescopes to learn more, such as the James Webb Space Telescope that launches in 2018. But here's a twist - one European team says it can do exoplanet science for a lot less.
ANALYSIS: ‘Habitable' Super-Earth Might Exist After All
With a budget of just 50 million pounds ($79 million), the Twinkle satellite team plans to launch into low-Earth orbit in three to four years if it can get the funding. There, it will study the infrared (heat) signatures of at least 100 nearby worlds a few hundred light-years away. This will be possible even with a tiny mirror of 50 centimeters (20 inches) compared to a larger telescope like Hubble (2.4 meters/8 feet), the lead scientist told Discovery News.
"We have identified a niche of science that could be done very well even with a relatively more modest instrument," said Giovanna Tinetti, an astrophysicist at University College London. Because the planets will be hothouse worlds that are relatively close by Earth, their infrared signatures are so strong that astronomers can infer the presence of molecules, clouds, weather and climate even in a small telescope, she said.
ANALYSIS: Exoplanet Forecast: Cloudy Morning. Outlook: Horrific Heat