It's been less than a month since Jim Bridenstine took over as the new chief of NASA. Still, the Bridenstine we see today is very different from the who testified in front of Congress.

Speaking at the NASA headquarters in Washington DC, Bridenstine took a few questions from the agency's employees. One of the questions was about a particularly controversial and politically-charged issue: climate denial.

You see, in the past, Bridenstine has questioned the primary role that humans play in climate change - a red flag for anyone running an agency that deals with climate and Earth science.

During his Senate committee hearing, Bridenstine side-stepped several simple questions about climate science.

When asked, for instance, to what extent humans have contributed to climate change, Bridenstine replied, "That is a question I do not have an answer to."

"Are they the primary cause?" Schatz said.

"It's going to depend on a whole lot of factors, and we're still learning more about that every day," Bridenstine said.

"In some years, you could say absolutely. In other years, during sun cycles and other things, there are other contributing factors that would have more of an impact."

Now, it looks as though Bridenstine has done a complete 180 on his beliefs. Replying to the NASA employee's question, Bridenstine said, "I don't deny the consensus that the climate is changing."

"In fact, I fully believe and know that the climate is changing. I also know that we humans beings are contributing to it in a major way," he continued.

"Carbon dioxide is a greenhouse gas. We're putting it into the atmosphere in volumes that we haven't seen, and that greenhouse gas is warming the planet. That is absolutely happening, and we are responsible for it."

To be fair, Bridenstine's change of heart doesn't come out of nowhere. After Bill Nye received criticism for attending the State of the Union with Bridenstine, Nye defended Bridenstine's nomination, saying that he was open-minded about climate change.

"During his recent nomination hearing, Congressman Bridenstine said that he now accepts climate change and that humans are playing a role in it," Nye told Quartz in a statement.

"He's changed his mind, and in science that's generally a good thing. I am hopeful that others will see the wisdom in the Congressman's evolving view and follow suit. Let's embrace the science and rise to the challenge of climate change."

Some people weren't buying it. Contrary to what Nye said, during his testimony, Bridenstine refused to acknowledge the primary role that humans play in climate change.

While it's true that Bridenstine also left this out of his most recent statement, saying that humans are contributing in a "major way," is a huge admission from a Trump nominee, and big step towards reality.

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