As 2021 began, we eagerly awaited the Perseverance rover’s arrival at Jezero Crater on Mars. The early part of the year was all about the Red Planet – with a successful rover landing and the first-ever helicopter flight on another world.
As the year progressed, our asteroid missions came into the spotlight. OSIRIS-REx started its journey back to Earth with precious cargo, and two new asteroid missions – Lucy and DART – launched to the skies.
Here’s the 2021 round-up of NASA planetary science, highlighting the year’s most spectacular images, the most ground-breaking discoveries, and the most incredible mission milestones.
February 18, 2021: Touchdown! The Perseverance Rover Lands on Mars
- Millions of people watched as Perseverance descended via parachute and jetpack to touch down on the Red Planet, ready to begin its multi-year mission to seek signs of ancient life and collect samples of rock for possible return to Earth. The rover has collected six samples so far, and sent home thousands of images, along with data about the geology, weather, and even the sounds of Mars. Perseverance is paving the way for human explorers in other ways too, such as testing technology for pulling oxygen from the Martian atmosphere.
March 18, 2021: Hubble Sees Changing Seasons on Saturn
This series of images taken in 2018, 2019, and 2020 by the Hubble Space Telescope shows slight changes in the atmosphere on Saturn’s northern hemisphere as the season changes from summer to fall after seven long Earth years of summer.Over three years, the equator got 5 to 10 percent brighter, and the winds changed slightly. In 2018, winds measured near the equator were about 1000 miles per hour (1609 kilometers per hour). In 2019 and 2020 the winds decreased to 800 miles per hour (1287 kilometers per hour). Can you spot the difference in the images? (Hint: Look at the north pole.)
April 19, 2021: Ingenuity’s First Flight
The Ingenuity helicopter was originally designed as a technology demonstration to test the feasibility of flying in the thin atmosphere of Mars. After being carried to the surface by the Perseverance rover, it completed five planned test flights. These went so well that the project transitioned into an operational demo phase, exploring how future rovers and aerial explorers can work together. Ingenuity has completed 18 successful flights so far. In this video from April 25, 2021, the helicopter takes off and lands, as seen by a camera aboard Perseverance. As expected, Ingenuity flew out of the camera’s field of vision while completing a flight plan that took it 164 feet (50 meters) downrange of the takeoff spot. Keep watching – the helicopter will return to stick the landing.
April 26, 2021: Image of Landslide in Klute Crater
Our Lunar Reconnaissance Orbiter has been at the Moon for over 12 years now and continues to capture incredible images of our natural satellite. In this image from the Narrow Angle Camera, the western wall of Klute crater on the far side of the Moon is slumped towards the crater floor, likely as a result of a nearby moonquake or surface impact event. Images like these demonstrate that the Moon is more geologically dynamic than we previously thought.
May 10, 2021: OSIRIS-REx Departs Bennu
For about two years, the OSIRIS-REx spacecraft orbited asteroid Bennu - a rubble-pile in space roughly as tall as the Empire State Building. In October 2020, Bennu descended to the asteroid’s surface to capture a sample of the material. In 2021, OSIRIS-REx left its asteroid to begin the 2.5-year-journey home. The sample collection itself has already taught us much about this common type of asteroid, but we’re promised to learn even more when OSIRIS-REx drops its sample off at our home planet in 2023.
Downloads: Full videos, images and captions
June 2, 2021: Venus Mission Selections
It’s been over 40 years since NASA sent a spacecraft to Venus and many many members of the planetary science community have long hoped for a mission to our sister planet. Scientists believe that Venus once resembled Earth and may have even been habitable, but now it's unbearably hot and covered in clouds of sulfuric acid. This year, NASA selected not just one mission, but TWO! The DAVINCI and VERITAS missions will complement each other’s science to provide a more complete view of this mysterious planet and understand how this planet that was once Earth-like became so… Venus-like.
June 7, 2021: Return to Ganymede
NASA’s Juno spacecraft came within 645 miles (1,038 kilometers) of the surface of Jupiter’s largest moon, Ganymede. It was the closest a spacecraft had passed by the solar system’s largest natural satellite since the Galileo mission in 2000. Along with striking imagery, Juno’s flyby yielded insights into the moon’s composition, ionosphere, magnetosphere, and ice shell. Ganymede is bigger than the planet Mercury and is the only moon in the solar system with its own magnetosphere, a bubble-shaped region of charged particles surrounding the celestial body.
Image: https://www.missionjuno.swri.edu/junocam/processing?id=10669 Image credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill © CC BY
August 11, 2021: OSIRIS-REx Provides Insight into Asteroid Bennu’s Future Orbit
Asteroid Bennu, the destination of our OSIRIS-REx mission, is classified as a hazardous near-Earth asteroid. Much like storms on Earth, we can’t fully predict the paths of asteroids because there are still factors not fully understood - like sunlight! Data gained from the spacecraft’s visit to Bennu helped us better define some of those factors to significantly improve models of the asteroid’s trajectory through the year 2135.
September 1, 2021: Perseverance Collects a Sample
On Sept. 1, NASA’s Perseverance rover unfurled its arm, placed a drill bit at the Martian surface, and drilled about 2 inches, or 6 centimeters, down to extract a rock core. The rover later sealed the rock core in an airtight titanium tube, making it available for future retrieval. This historic event marked the first time a spacecraft packed up a rock sample from another planet that could be returned to Earth by future spacecraft. Mars Sample Return is a multi-mission campaign designed to retrieve the cores Perseverance will collect over the next several years. Currently, in the concept design and technology development phase, the campaign is one of the most ambitious endeavors in spaceflight history, involving multiple spacecraft, multiple launches, and dozens of government agencies.
September 15, 2021: NASA Confirms Thousands of Ancient, Martian Volcanic Eruptions
Using data from the Mars Reconnaissance Orbiter and modeling, scientists from NASA Goddard Space Flight Center and Johns Hopkins Applied Physics Laboratory found evidence that a region of northern Mars called Arabia Terra experienced thousands of "super eruptions," the biggest volcanic eruptions known, over a 500-million-year period.
October 16, 2021: Lucy Mission Launches to the Trojan Asteroids
On October 16, the Lucy mission launched from Kennedy Space Center. Lucy will travel for six years before it reaches its destination: Jupiter’s Trojan asteroids. These planetary building blocks have been trapped within Jupiter’s orbit for 4.5 billion years and can reveal important information about the beginnings of our solar system. But that’s looking ahead. This year, we watched in awe as Lucy soared into space, and then we marked the moment in our #LucyTimeCapsules.
November 24, 2021: The First Planetary Defense Mission, DART, Launches
NASA’s Double Asteroid Redirection Test (DART) is the world’s first mission to test technology for protecting Earth against potential asteroid or comet hazards. Just one part of NASA’s larger planetary defense strategy, DART will travel to a distant asteroid named Didymos, which is not a threat to Earth. Didymos has a tiny moonlet called Dimorphos, about 530 feet (160 meters) wide…and the DART spacecraft will intentionally slam right into it. The goal? Change the moonlet’s motion slightly – just enough so that it can be measured using telescopes millions of miles away here on Earth. What the DART test reveals could be invaluable if Earth is ever threatened by a larger object from space. Check out our 3D simulation “Eyes on Asteroids” to see more.
December 25, 2021: Webb Space Telescope Launch
NASA’s James Webb Space Telescope launched at 7:20 a.m. EST Saturday on an Ariane 5 rocket from Europe’s Spaceport in French Guiana, South America.
A joint effort with ESA (European Space Agency) and the Canadian Space Agency, the Webb observatory is NASA’s revolutionary flagship mission to seek the light from the first galaxies in the early universe and to explore our own solar system, as well as planets orbiting other stars, called exoplanets.
“The James Webb Space Telescope represents the ambition that NASA and our partners maintain to propel us forward into the future,” said NASA Administrator Bill Nelson. “The promise of Webb is not what we know we will discover; it’s what we don’t yet understand or can’t yet fathom about our universe. I can’t wait to see what it uncovers!”
Ground teams began receiving telemetry data from Webb about five minutes after launch. The Arianespace Ariane 5 rocket performed as expected, separating from the observatory 27 minutes into the flight. The observatory was released at an altitude of approximately 870 miles (1,400 kilometers). Approximately 30 minutes after launch, Webb unfolded its solar array, and mission managers confirmed that the solar array was providing power to the observatory.