Neil Armstong and Buzz Aldrin stepping down onto the moon's surface in 1969 was a single moment that stemmed from a decade's worth of work--and a challenge from President Kennedy. Kennedy stood on the Congress floor in 1961 and challenged the U.S. to arrive there first, and thus the term "moonshot" entered the popular lexicon.

"That speech came at a time of cultural and political turmoil, when national and economic security dominated the headlines," Gates wrote in a blog post Thursday. "President Kennedy believed looking to the skies would inspire the country to dream big and accomplish huge things." The resulting space race didn't only get us to the moon--it also helped us launch the satellites that today let us understand the Earth's weather patterns and help us communicate across the world.

The government's role is a big one when it comes to groundbreaking innovation. As Gates points out, computers were massive and expensive in the 1960s, until U.S. government research helped bring about microchips and the internet--and now, unsurprisingly, most of the leading computer hardware and software companies are based in America.

According to the Microsoft founder, here are the four moonshots the U.S. government should try to achieve in the next decade if it wants to inspire the kind of innovation that can change the world.

1. Affordable, sustainable energy.

Plenty of companies are trying to develop sources of energy that don't depend on fossil fuels. Elon Musk's SolarCity, in the midst of a controversial acquisition by Tesla, wants to create solar roofs that provide power not only to homes, but to cars as well. Rayton Solar is trying to significantly reduce the cost of solar panels by revamping the process by which silicon panels are created. And Solar Roadways is experimenting with solar energy-producing sidewalks and roadways at a rest stop in Missouri.

In 2015, 21 countries including the U.S. committed to doubling the amount they spend annually on clean energy research. But if the government invests even more heavily in clean energy research, Gates says, the odds of a breakthrough go up--and then the companies that can take that technology to market will win, as will the entire world.

2. Cures for HIV and neurodegenerative diseases like Alzheimer's.

More than one million people die from AIDS each year--an enormous number, but one that has decreased steadily throughout the past decade thanks in large part to anti-retroviral medicines that can slow its spread within the body. "Based on recent progress, I believe world leaders could help make an effective AIDS vaccine a reality within the next decade," Gates says. "And with a vaccine, we would be on the path to ending the disease altogether."

Meanwhile, scientists are developing drugs that can slow the onset of symptoms of neurodegenerative diseases, like Alzheimer's. "New digital tools and the rapid advancement of science are providing new momentum and hope in the search for cures," Gates writes.

3. Protection from future health epidemics.

The outbreak of Ebola virus in West Africa in 2014, and the worldwide panic it caused, served as a wake-up call: We as a human race are still extremely vulnerable to fast-spreading, infectious diseases. "There is a significant chance that a substantially more infectious epidemic will come along during the next decade," Gates writes rather glumly. The key, he says, will be getting our scientific process to the point at which we can detect a disease, develop a test for it, and create a cure in a short amount of time. While Ebola spread, companies ranging from the $40 billion British pharma giant GSK to nine-employee startup Mapp Biopharmaceutical all worked quickly to develop drugs to combat it, though no one is yet to create a proven antidote. "With vision and support, we will be able to identify and prevent epidemics before they devastate families, communities, and economies," Gates says.

4. Tools to provide a world-class education to all students.

As technology advances, so do the ways that teachers and students interact. A few big advantages of tech in the classroom: instant quiz results and feedback; more personalized learning; lessons that can be watched again or viewed from remote locations. Plenty of startups, like New York-based Newsela, which teaches reading comprehension, and coding startup Future League, are creating tools for use in the classroom. "Funding for government research budgets would boost the market and help identify the most effective approaches," Gates says, "giving teachers and students new tools that empower them to do their best work." And it's a virtuous cycle: A great education can help breed the next generation of thinkers and innovators.