Gisele Bündchen, 29, was out and about showing off her baby bump this weekend, looking cuter than ever! The supermodel, who is expecting her first child with hubby Tom Brady in December, isn't letting pregnancy slow her down one bit.

According to reports, the Brazilian bombshell has been learning how to fly on her downtime. She's been taking flying lessons at the Marshfield Airport in Massachusetts for a few weeks and is well on her way to obtaining her helicopter pilot's license. But Bündchen's most important new assignment is a goodwill ambassadorship that the United Nations recently offered the mom-to-be. "I'm really honored to have received a call from the UN to spread the message about climate change in the world."

The environment has long been an important cause of Bündchen's. "I started paying attention to what was happening with the environment when I had a visit to the Xingu area of the Amazon in 2003," she told reporters during an appearance in Manhattan's Washington Square. "I spent a week with an Indian tribe and everyone was complaining they were getting sick because the waters were polluted. I was like, 'Who is doing something about this?'" 

Since then, Bündchen started a charity called Agua Limpia and joined forces with the United Nation's Environmental Program to help spread the word. “We must act now, so future generations have the same opportunity," she said, "Mother Earth is our fundamental life-support system, and by becoming aware and responsible now, we can assist in preserving the planet."