Several ground-breaking NASA missions are already in progress, including the Parker Solar Probe, which will rocket past the sun a total of 24 times.
Launched: August 12, 2018
Arrived: November 5, 2018
The probe is traveling closer to the sun than anything from Earth before it. The mission aims to investigate the forces behind solar wind, which could inform efforts to protect technology on Earth from the sun's flare-ups.
Parker slingshots around the sun at record speeds of up to 213,200 mph; it just finished its third close encounter. A powerful heat shield keeps the spacecraft's equipment cool.
Far from the sun, New Horizons is exploring the Kuiper Belt, a region of millions of chunks of ice left over from the solar system's birth.
Launched: January 19, 2006
Arrived at Ultima Thule: January 1, 2019
The New Horizons spacecraft visited Pluto and the ice dwarfs surrounding it in 2015. In January, the spacecraft reached the farthest object anything human-made has ever visited: a snowman-shaped space rock called 2014 MU69 (or Ultima Thule).
It sent back the following video of Ultima Thule, though it will likely take until late 2020 for scientists to receive and download all the data from New Horizons' flyby.
So far, we've learned that the primordial object contains methanol, water ice, and organic molecules.
On the surface of Mars, the InSight lander is listening for quakes.
Launched: May 5, 2018
Arrived: November 26, 2018
Since the InSight lander touched down on the surface of the red planet, it has detected dozens of Mars quakes. The early data is giving scientists new insight into the planet's internal structure.
A new Mars rover will join InSight next year. NASA is currently building the vehicle in its Jet Propulsion Laboratory in Pasadena, California.
Planned launch: July 2020
Anticipated arrival: February 2021
The Mars 2020 rover will search for signs of ancient microbial alien life on the red planet, collect and stash rock samples, and test out technology that could pave the way for humans to walk the Martian surface one day.
You can tune in to NASA's live broadcast of the Mars 2020 rover's construction anytime to watch the $2.1 billion mission take shape.
Researchers hope a future mission to Mars could return the Martian rock samples that the Mars 2020 rover collects back to Earth.
Planned launch: Unknown
Anticipated arrival: Unknown
Until NASA sends another robot to Mars that could launch the stored samples to Earth, the 2020 rover will store the samples in its belly and search for a place on Mars where it can stash them for pickup.
NASA eventually hopes to send a crewed mission to Mars. But before that, the agency plans to return astronauts to the moon and build a lunar base there.
Planned launch: Unknown
Anticipated arrival: 2024
NASA wants to send humans to the moon again by 2024. Those would be the first boots on the lunar surface since the Apollo program ended over 45 years ago. This time, however, NASA wants to build a moon-orbiting space station with a reusable lunar-landing system.
The idea is that the lunar base could allow for more in-depth scientific research of the moon, and potentially even enable us to mine resources there that could be converted to fuel for further space travel.
From the lunar surface, astronauts may springboard to Mars.
Planned launch: 2030s
Anticipated arrival: 2030s
The next moon mission will test deep-space exploration systems that NASA hopes will carry humans on to Mars.
Astronauts traveling to Mars would have to spend about three years away from Earth. In order to explore the red planet, any potential human travelers would probably need to use materials from the lunar and Martian surfaces.
NASA is already designing future astronauts' gear. They're sending spacesuit material on the Mars 2020 rover to test how it holds up in the planet's harsh atmosphere. A deep-space habitat competition this year yielded a 3D- printable pod that could be constructed using materials found on Mars.
NASA also plans to investigate our solar system's past by launching a mission to an asteroid belt that surrounds Jupiter.
Planned launch: October 2021
Anticipated arrival: 2027
A mysterious swarm of Trojan asteroids — the term for space rocks that follow planets — trail Jupiter's orbit around the sun. NASA's Lucy mission plans to visit six of them.
"We know very little about these objects," Jim Green, the leader of NASA's planetary science program, said in a NASA video. "They may be captured asteroids, comets, or even Kuiper Belt objects."
What we do know is that the objects are as old as the sun, so they can serve as a kind of fossil record of the solar system.
Relatively nearby, a spacecraft will scan for alien life in the saltwater ocean on Jupiter's moon Europa.
Planned launch: 2020s
Anticipated arrival: Unknown
When Galileo Galilei first looked at Jupiter through his homemade telescope in 1610, he spotted four moons circling the planet. Nearly 400 years later, NASA's Galileo mission found evidence that one of those moons, Europa, conceals a vast ocean of liquid water beneath its icy crust.
NASA is planning to visit that ocean with the Europa Clipper, a spacecraft that will fly by the moon 45 times, getting as close at 16 miles above the moon's surface.
Clipper will fly through water vapor plumes that shoot out from Europa's surface (as seen in the NASA visual above) to analyze what might be in the ocean. Radar tools will also measure the thickness of the ice and scan for subsurface water.
That investigation could help scientists prepare to land a future spacecraft on Europa's surface and punch through the ice.
Anticipated launch and arrival: Unknown
The future lander would search for signs of life in the ocean, digging 4 inches below the surface to extract samples for analysis in a mini, on-the-go laboratory.
A nuclear-powered helicopter called Dragonfly will take the search for alien life one planet further, to Saturn's largest moon, Titan.
Planned launch: 2026
Anticipated arrival: 2034
Titan is a world with ice, liquid methane pools, and a thick nitrogen atmosphere. It somewhat resembles early Earth, since it has carbon-rich organic materials like methane and ethane. Scientists suspect that an ocean of liquid water might lurk 60 miles below the ice.
All that makes Titan a contender for alien life.
But getting to the distant, cold moon is not easy — Saturn only gets about 1% of the sunlight that bathes Earth, so a spacecraft can't rely on solar energy. Instead, Dragonfly will propel itself using the heat of decaying plutonium.
Another NASA team is developing a spacecraft to probe the metal core of a dead planet called Psyche.
Planned launch: 2022
Anticipated arrival: 2026
Most of the asteroids in our solar system are made of rock or ice, but Psyche is composed of iron and nickel. That's similar to the makeup of Earth's core, so scientists think Psyche could be a remnant of an early planet that was decimated by violent collisions billions of years ago.
NASA is sending a probe to find out.
"This is an opportunity to explore a new type of world – not one of rock or ice, but of metal," Linda Elkins-Tanton, who's leading the mission, said in a press release. "This is the only way humans will ever visit a core."
If Psyche really is the exposed core of a dead planet, it could reveal clues about the solar system's early years.
The probe NASA plans to send to Psyche would be the first spacecraft to use light, rather than radio waves, to transmit information back to Earth. The agency gave the team the green light to start the final design and early assembly process in June.
NASA also has 176 missions in the works that use CubeSats: 4-by-4-inch cube-shaped nanotechnology satellites.
NASA is partnering with 93 organizations across the US on these CubeSat projects. Such satellites have already been built and sent to space by an elementary school, a high school, and the Salish Kootenai College of the Flathead Reservation in Montana.
The first CubeSats sent to deep space trailed behind the InSight Mars lander last year. They successfully sent data from the InSight lander back to Earth as it landed on the Martian surface.
One planned mission using the nanotechnology will use lasers to search for ice on the moon's shadowy south pole. It's expected to launch in November 2020. Another CubeSat mission, also set to launch in 2020, will fly past an asteroid near Earth — the first exploration of an asteroid less than 100 meters in diameter.
The data the satellite sends back could help scientists plan for future human missions to asteroids, where astronauts might mine resources as they explore deep space.
Closer to home, the European Space Agency's Euclid telescope will study dark matter and dark energy.
Planned launch and arrival: 2022
Dark matter makes up 85% of the universe, but nobody is sure what it is. Part of the problem is that we can't see it, because it doesn't interact with light.
Dark matter's gravity holds the entire universe together, while an unknown force called dark energy pushes everything apart. Dark energy is winning, and that's why the universe is expanding.
As Euclid orbits Earth, the space telescope will measure the universe's expansion and attempt to map the mysterious geometry of dark matter and energy.
NASA is working with the ESA on imaging and infrared equipment for the telescope.
The James Webb Space Telescope, which has a massive, 18-panel mirror, will scan the universe for life-hosting planets and attempt to look back in time to photograph the Big Bang.
Planned launch and arrival: 2021
It's been almost 30 years since the Hubble Space Telescope launched. The James Webb Space Telescope is its planned replacement, and it packs new infrared technology to detect light beyond what the human eye can see.
The telescope's goal is to study every phase of the universe's history in order to learn about how the first stars and galaxies formed, how planets are born, and where there might be life in the universe.
A 21-foot-wide folding beryllium mirror will help the telescope observe faraway galaxies in detail. A five-layer, tennis court-size shield protects it from the sun's heat and blocks sunlight that could interfere with the images.
The James Webb Space Telescope will be capable of capturing extremely faint signals. The farther it looks out into space, the more it will look back in time, so the telescope could even detect the first glows of the Big Bang.
The telescope will also observe distant, young galaxies in detail we've never seen before.
The Wide Field InfraRed Survey Telescope (WFIRST) is expected to detect thousands of new planets and test theories of general relativity and dark energy.
Planned launch and arrival: mid-2020s
WFIRST's field of view will be 100 times greater than Hubble's. Over its five-year lifetime, the space telescope will measure light from a billion galaxies and survey the inner Milky Way with the hope of finding about 2,600 exoplanets.
On Monday, NASA added a new Earth-orbiting telescope to its agenda. Its infrared cameras will be designed to detect near-Earth objects (NEOs) — one of the greatest threats to life on Earth.
Planned launch and arrival: Unknown — 2025 at the earliest
"This is a great step forward for thinking about human destiny, because the dinosaurs certainly did not have an asteroid-survey program to protect themselves," Richard Binzel, an asteroid researcher and professor of planetary sciences at MIT, told Business Insider. "Having knowledge of what's out there is something that the planetary science community has been advocating for for nearly 30 years. So this is a breakthrough decades in the making."
The mission will be based on previous plans for a similar telescope, NEOCam, which was never fully funded.
Eventually, an asteroid-hunting telescope could help us avoid surprises like the "city-killer" asteroid that flew within 45,000 miles of Earth in July and went unnoticed until it was just days away.