Astrophysicist Neil deGrasse Tyson has a word for those who think Pope Francis shouldn't comment on climate change.
The pope released an encyclical, or papal letter, in June that not only affirmed climate change was happening but also blamed human negligence and pointed to science to support the need for reducing carbon emissions.
"Numerous scientific studies indicate that the majority of the global warming in recent decades is due to the large concentration of greenhouse gases ... emitted above all due to human activity," the encyclical read.
Though many applauded the pope's letter, some objected to the religious leader taking a stand on scientific matters. Days before the long-awaited encyclical was released, Republican presidential candidate Rick Santorum told a Philadelphia radio station: “The church has gotten it wrong a few times on science, and I think we probably are better off leaving science to the scientists and focusing on what we’re good at, which is theology and morality.”
Tyson, host of the popular podcast StarTalk and winner of the U.S. National Academy of Sciences Public Welfare Medal, begs to differ. The scientist took to Twitter on Tuesday to stand up for Pope Francis and his petition for the environment:
Katharine Hayhoe, an atmospheric scientist and professor at Texas Tech University, agreed with Tyson.
"Science can tell us whether climate is changing or not. Science can tell us why it's changing. ... Science can tell us what the consequences of our actions will be. But science can't tell us what is the right thing to do because that's a value decision," she told The Huffington Post. "That's why it's important to have leaders speak up on values because the values are what determine what we decide to do."
With his message, Hayhoe added, the pope "is speaking up and giving a voice to people who often don't have a voice in our world" -- namely, poor and disenfranchised people around the globe who are most affected by climate change.
The Vatican does, as Tyson notes, have a robust observatory, in addition to the Pontifical Academy of Sciences. Since 1902, the academy has counted 70 Nobel laureates among its members.
For his part, Pope Francis has a background in science, having worked as a chemist before entering seminary. He also promotes the use of science to better understand creation and argues that the Big Bang is not incompatible with the notion of God.