Whoever takes up Elon Musk's latest challenge could be in for a financial windfall – but it would benefit everyone on the planet. Musk – the founder of Tesla and SpaceX – tweeted he would donate $100 million towards a prize for designing effective carbon capture technology, with other details to come at a later date. The announcement comes after 49-year-old Musk briefly surpassed Amazon founder Jeff Bezos as the world's richest person earlier this month. On January 7, Musk asked his followers for "critical feedback" and ways to "donate money that really make a difference." His follow-up tweet last week said, "Am donating $100M towards a prize for best carbon capture technology." But what is "carbon capture technology," and why does Musk seem to care about it? Controlling carbon dioxide (CO2) levels in the atmosphere is an important step in the fight against climate change. Carbon dioxide is emitted by the burning of fossil fuels, such as coal and oil. Plants absorb carbon dioxide from the atmosphere through a process called photosynthesis, but in the modern world, carbon dioxide is inundating the environment at a dangerous rate through the use of gasoline-dependent vehicles and the burning of wood and coal. A large level of carbon dioxide returning to the atmosphere over the decades since the start of the Industrial Revolution has contributed to warming temperatures around the Earth. If humans can devise technology that can extract, or "capture," carbon dioxide from the atmosphere, it could help in efforts to slow the climate crisis.