Perseverance, NASA's most sophisticated rover to date, is expected to land on the surface of Mars on Thursday, Feb. 18, around 3:55 p.m. ET.
The rover has been traveling through space since launching from Cape Canaveral, Florida, at the end of July. When it reaches Mars, Perseverance will have traveled 292.5 million miles on its journey from Earth.
Perseverance is NASA's first mission that will search for signs of ancient life on another planet to help answer the big question: Was life ever present on Mars? The rover will explore Jezero Crater, the site of an ancient lake that existed 3.9 billion years ago, and search for microfossils in the rocks and soil there.
Along for the ride with Perseverance is an experiment to fly a helicopter, called Ingenuity, on another planet for the first time.
Here's what to expect this week.
A rendering of 's Perseverance rover on Mars. The probe is due to arrive at the red planet in February 2021.
How to watch
Unfortunately, we can't watch the SUV-size rover land on the surface of Mars — we're just not there yet, technologically speaking.
But NASA is inviting the world to tune in to its countdown and landing commentary, which will stream live beginning on Thursday at 2:15 p.m. ET. Tune in via NASA's public TV channel, website, app, YouTube, Twitter, Facebook, LinkedIn, Twitch, Daily Motion or THETA.TV. In a first, the agency will also offer a Spanish language show for the landing.
During the landing coverage, NASA's mission control team will be able to confirm if the rover safely landed on the surface of Mars.
Naturally, the rover has its own Twitter and Facebook accounts, where you can expect updates from the mission team from the perspective of the rover. And you can bet the Curiosity rover and InSight lander will be welcoming Perseverance to their home, the red planet.
Perseverance, NASA's most sophisticated rover to date, is expected to land on the surface of Mars on Thursday, February 18, around 3:55 p.m. ET.
The agency has fun ways to participate in the countdown excitement, like photo booths and activities for kids and students. You can also follow every step of the rover's landing through a NASA interactive or sign up for a virtual experience of the landing.
"If there's one thing we know, it's that landing on Mars is never easy," said Marc Etkind, NASA associate administrator for communications, in a statement. "But as NASA's fifth Mars rover, Perseverance has an extraordinary engineering pedigree and mission team."
Just weeks after the landing, if all goes according to plan, cameras and microphones on the spacecraft will show the rover's perspective for the first time.
The rover has been traveling through space since launching from Cape Canaveral, Florida, at the end of July. When it reaches Mars, Perseverance will have traveled 292.5 million miles on its journey from Earth.
Landing on Mars: '7 minutes of terror'
If successful, Perseverance will be NASA's ninth landing on Mars. First, it has to go through the infamous "seven minutes of terror."
The one-way time it takes for radio signals to travel from Earth to Mars is about 10.5 minutes, which means the seven minutes it takes for the spacecraft to land on Mars will occur without any help or intervention from NASA teams on Earth.
The ground teams tell the spacecraft when to begin EDL (entry, descent and landing) and the spacecraft takes over from there — and mission control begins an agonizing wait.
In this illustration, NASA's Mars 2020 rover uses its drill to core a rock sample on Mars.
This rover is the heaviest NASA has ever attempted to land, weighing in at over a metric ton.
The spacecraft hits the top of the Martian atmosphere moving at 12,000 miles per hour and has to slow down to zero miles per hour seven minutes later when the rover softly lands on the surface.
The spacecraft's heat shield will endure peak heating of 2,370 degrees Fahrenheit, 75 seconds after entering the atmosphere.
Perseverance is targeting a 28-mile-wide ancient lake bed and river delta, the most challenging site yet for a NASA spacecraft landing on Mars. Rather than being flat and smooth, the small landing site is littered with sand dunes, steep cliffs, boulders and small craters. The spacecraft has two upgrades — called Range Trigger and Terrain-Relative Navigation — to navigate this difficult and hazardous site.
This illustration shows the events that occur in the final minutes of NASA's Perseverance rover for it to land on the Martian surface.
Range Trigger will tell the 70.5-foot-wide parachute when to deploy based on the spacecraft's position 240 seconds after entering the atmosphere. After the parachute deploys, the heat shield will detach.
The rover's Terrain-Relative Navigation acts like a second brain, using cameras to take pictures of the ground as it rapidly approaches and determines the safest spot to land. It can shift the landing spot by up to 2,000 feet, according to NASA.
The back shell and parachute separate after the heat shield is discarded — that will happen when the spacecraft is 1.3 miles above the Martian surface. The Mars landing engines, which include eight retrorockets, will fire to slow the descent from 190 miles per hour to about 1.7 miles per hour.
Then, the famed sky crane maneuver that landed the Curiosity rover will occur. Nylon cords will lower the rover 25 feet below the descent stage. After the rover touches down on the Martian surface, the cords will detach and the descent stage will fly away and land at a safe distance.
The mission: What the rover will do
Once the rover has landed, Perseverance's two-year mission will begin. First, it will go through a "checkout" period to make sure it's ready.
Perseverance will search for evidence of ancient life and study Mars' climate and geology and collect samples that will eventually be returned to Earth by the 2030s.
For that reason, Perseverance is also the cleanest machine ever sent to Mars, designed so it doesn't contaminate the Martian samples with any microbes from Earth that could provide a false reading.
Jezero Crater was chosen as Perseverance's home because billions of years ago, the basin was the site of a lake and river delta. Rocks and dirt from this basin could provide fossilized evidence of past microbial life, as well as more information about what ancient Mars was like.
This mosaic of images collected by the Mars Reconnaissance Orbiter shows a possible route the Mars 2020 Perseverance rover could take across Jezero Crater.
"Perseverance's sophisticated science instruments will not only help in the hunt for fossilized microbial life, but also expand our knowledge of Martian geology and its past, present, and future," said Ken Farley, project scientist for Mars 2020, in a statement.
The path Perseverance will traverse is about 15 miles long, an "epic journey" that will take years, Farley said. What scientists could discover about Mars, though, is worth the journey. To accomplish its goals, Perseverance will drive a little less than 0.1-miles per hour, three times faster than previous rovers.
Perseverance also carries instruments that could help further exploration on Mars in the future, like MOXIE, the Mars Oxygen In-Situ Resource Utilization Experiment. This experiment, about the size of a car battery, will attempt to convert Martian carbon dioxide into oxygen.
Not only could this help NASA scientists learn how to produce rocket fuel on Mars, but also oxygen that could be used during future human exploration of the red planet.
Perseverance will be able to observe Ingenuity's flight.
Ingenuity, the first helicopter on another planet
Perseverance isn't traveling to Mars by itself. Along for the ride is Ingenuity, which will be the first helicopter to fly on another planet.
After landing, the rover will also find a nice, flat surface to drop the Ingenuity helicopter so it has a place to use as a helipad for its potential five test flights during a 30-day period. This will occur within the first 50 to 90 sols, or Martian days, of the mission.
Once Ingenuity is settled on the surface, Perseverance will drive to a safe spot at a distance and use its cameras to watch Ingenuity's flight.
NASA's Mars 2020 rover will store rock and soil samples in sealed tubes on the planet's surface for future missions to retrieve, as seen in this illustration.
Ingenuity weighs only 4 pounds and features four carbon-fiber blades, solar cells and batteries.
Mars has an incredibly thin atmosphere, so the design for Ingenuity had to be lightweight, while including larger and faster rotors than those of typical helicopters on Earth to get it up in the air.
If Ingenuity is successful, it could pave the way for more advanced robotic aircraft to be used on future missions to Mars, both robotic and human, according to NASA.
25 things we've learned about the moon since 1969
For centuries, the moon has been an endless source of fascination for mankind. Sitting roughly 240,000 miles from Earth, it is our only natural satellite and the largest visible object in the night sky. It has been lauded by poets, thought to affect our moods, and has been studied by scientists and stargazers alike. The moon isn’t just a pretty view through a telescope, however—it plays an important part in keeping our planet stable and livable.
In 1969, NASA took its “one giant leap for mankind,” making history by putting a man on the moon for the first time. During its Apollo missions in the late ’60s and ’70s, the space program sent a total of nine missions to the moon, with six of those missions landing astronauts to explore the surface. The data collected by the moon landings not only helped scientists learn about the moon itself, but also how it affects our own planet. Today, NASA has three robotic spacecraft orbiting the moon, the Lunar Reconnaissance Orbiter (LRO), which was created to make a 3D map of the Moon’s surface, and the two ARTEMIS spacecraft probes, launched in 2011 to provide data on solar wind.
This ongoing research has greatly expanded what we know about the moon since that first NASA launch. Stacker decided to break down some of those facts and compile a list of 25 things we’ve learned about the moon since 1969. Resources used include data from NASA, the Smithsonian, and breaking news reports, with the aim of creating a comprehensive list of these monumental discoveries about our universe.
Click through for a look at all the things science has learned about the moon since 1969.
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The moon is lifeless
Research has shown that the moon has no living organisms, including fossils or native compounds. There are some traces of nonbiological organic compounds, but those are attributed to contamination by meteorites.
The moon is about 4.5 billion years old
It is thought that the moon was formed after a large object or series of objects slammed into Earth, with some of the material exploding into space and creating our lunar neighbor. After Apollo astronauts brought back lunar rocks for analysis, scientists studied ancient zircon fragments and were able to determine that this took place approximately 4.5 billion years ago.
The moon is not primordial—it evolved
The moon is considered an evolved terrestrial planet made of rocky material that has been melted, crushed by meteorites, and erupted by volcanoes. Its internal zoning is actually similar to Earth’s, with a thick crust, lithosphere, and “partly liquid asthenosphere,” according to NASA.
The moon is shrinking
After reviewing moonquake data collected between 1969 and 1977, scientists determined that approximately 25% of the moon’s seismic activity was generated by released energy from scarps, or stairstep cliffs on the moon’s surface. This activity comes from the contraction of the moon's crust as it cools, which has caused it to shrink by about 150 feet over the last several hundred million years.
There is water on the moon...
When the Apollo astronauts first explored the moon, they thought it was a dry planet. However, in 2009, NASA’s Lunar Reconnaissance Orbiter produced data that showed water locked up in ice. As the moon warms and cools throughout the day, those water molecules actually float around until finding areas cool enough to settle back onto the lunar surface.
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...and not just in cold, dark places
NASA recently detected water on sunlit portions of the moon. The agency’s Stratospheric Observatory for Infrared Astronomy (SOFIA) detected water molecules in Clavius Crater, located in the southern hemisphere, a sunlit side of the moon. Data indicated water concentrations of 100 to 412 parts per million in a cubic meter of soil, which is about the equivalent of a 12-ounce bottle of water.
The solar wind changes
The Apollo 11 mission was the first to deploy what was known as the Solar Wind Composition Experiment, which involved an aluminum foil sheet attached to a pole. The sheet was unfurled and exposed to the sun for 77 minutes, then collected and transported back to Earth to be analyzed. The data was collected from the sheets over many years of the Apollo missions, helping scientists determine variations in the composition and intensity of solar winds.
The youngest rocks from the moon are as old as Earth's oldest rocks
While the Earth’s oldest surfaces are always being repaved by geological forces such as erosion and the shifting of tectonic plates, the moon’s surface exists with minimal disturbance. Moon rocks range from 3.2 billion years old in the darker regions to almost 4.6 billion years in those areas with more light.
The moon’s craters were caused by asteroid impacts
The surface of the moon is covered with craters, the majority of which were formed by meteorites colliding with the lunar surface. While meteorites have also hit Earth, the planet’s atmosphere helps protect it from impact, and geologic activity such as weather and volcanoes erode signs of impact. The moon has virtually no geologic activity or atmosphere, so lunar craters from billions of years ago are still visible.
Its crust offers perspective on other planets
Because it doesn’t have an atmosphere, volcanoes, or plate tectonics to disrupt it, the moon’s crust is very well-preserved. Scientists have been able to determine the age of lunar surfaces, and data collected from moon samples helps them to estimate the ages of other planets.
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The Earth and moon are genetically related
Similar compositions of moon and earth rocks have led scientists to determine common ancestry between the two. Unlike the Earth, however, the moon does not have enough iron or other elements to form atmospheric gas or water.
The lunar surface is solid
Scientists originally thought the moon was covered with a layer of unknown material, with no real knowledge of what that material might be or how safe it would be for astronauts to explore it. After studying the observations of the Apollo 11 astronauts and the samples they took from the lunar surface, they were able to determine that it is a mix of grains of dust and large rocks.
The moon is seismically active
As part of the Apollo space program, seismometers were placed on the surface of the moon. They were retired in the late ’70s, but during the time they were actively recording seismic activity on the moon, there were 28 moonquakes of varying magnitudes. Later research via the Lunar Reconnaissance Orbiter showed fault lines in the moon that are less than 50 million years old, as well as the displacement of boulders across the surface, both of which point to the occurrence of regular moonquakes.
The moon is covered with rocks and dust called regolith
Samples collected by Apollo 11 show that the moon is covered with regolith, a mix of dust and rock fragments. Due to the lack of atmosphere, the regolith is also exposed to micrometeorites and solar wind irradiation, which breaks up its rocks and melts portions of it, creating bits of volcanic glass fragments.
Moon rocks were formed in high temperatures without water
The consistency of the moon’s rocks fall into three basic categories: basalts, which fill the mare basins and look like lava, anorthosites, which are lighter rocks that resemble those on Earth, and breccias, which are composite rocks formed from others crushed and mixed by meteorite impact. Despite the fact that there is water on the moon, all three types of moon rocks are formed without water, whereas on Earth, water plays a big role in the creation of rocks such as shale or limestone.
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There's a huge reserve of heavy metal under the moon's South Pole
Scientists aren’t sure where it came from, but there is a giant deposit of heavy metal lodged underneath the moon’s South Pole-Aitken basin. It is estimated to weigh around 2.4 quadrillion tons and is thought to possibly be the remains of an iron-nickel asteroid that crashed into the moon 4 billion years ago.
The moon has at least two lunar pits
Data gathered from NASA’s moon probe, the Lunar Reconnaissance Orbiter, has shown images of at least two large holes in the moon known as lunar pits. The holes are thought to form when a subterranean lava tube collapses, although the Mare Ingenii pit lies in an area that has few volcanic features. While impact craters are all over the moon’s surface, lunar pits are considered rare.
The moon has a crust, mantle, and core—just like Earth
Apollo 11’s Passive Seismic Experiment, which detected and measured moonquakes, also helped scientists determine that there is a small core at the moon’s center. Subsequent seismometers deployed during Apollo 12, 14, 15, and 16 revealed even more information, with data indicating a lunar crust that is 37-44 miles thick—or about three times the thickness of Earth’s crust.
The Earth and moon trade meteorites
Scientists and researchers have found meteorites on Earth that were ejected from the moon. Asteroid impacts on the moon expel meteorites into space, bringing with them lunar rock from all areas of the moon’s surface. Studies also suggest that rocks from Earth travel to the moon, and computer simulations have led scientists to believe that the moon may have asteroid debris from Earth, Venus, and Mars.
The moon is moving away from Earth
The pace is minuscule, but there’s no doubt the moon is slowly receding from the Earth. During their mission, Apollo 11 astronauts placed a Laser Ranging Retroreflector on the moon’s surface, which helps measure the distance between Earth and the moon. The Retroreflector, a series of mirrors that reflect laser pulses, shows that the moon is retreating at a rate of about 1.5 inches per year.
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Moonquakes can last up to 10 minutes
Unlike earthquakes, which usually only average about 30 seconds, moonquakes can go on for quite some time. These shallow tremors originate 12-19 miles below the lunar surface and last upward of 10 minutes. While scientists aren’t sure what causes these long quakes, the activity has helped them to understand early seismic activity on Earth, as well as the role liquid water plays on our planet by spreading energy caused by quakes, thus softening their vibrations.
When it was still very young, the moon melted to form a magma ocean
Between approximately 4.4 and 4.6 billion years ago, a magma ocean tens of kilometers deep covered the moon. An early crust on that ocean formed what became the lunar highlands, and meteorite impact reduced that crust more, creating mountain ranges that built up between the impact basins.
The moon's gravity helps strengthen Earth's shield
Earth has a magnetic field created by the movement of liquid iron and nickel in the outer core that helps protect it from destructive natural forces like solar wind or cosmic particles. Scientific research of how the moon’s gravity affects the planet indicates that it “tugs” on the Earth’s mantle, which sits on top of that liquid outer core, and causes the liquid to move around, helping to generate energy that strengthens Earth’s shield.
The moon is asymmetrical
It might look perfectly round when it's full, but the moon is actually asymmetrical. Its crust is thicker on one side than the other, and there are large masses beneath the surface of many lunar basins potentially caused by accumulations of lava. Scientists believe the unevenness and asymmetry could be a result of Earth’s gravitational pull.
The moon's Hermite Crater is home to the coldest temperature ever measured in the solar system
NASA’s Lunar Reconnaissance Orbiter was able to detect a location in the moon’s Hermite Crater that was minus 415°F, colder than any other temperature recorded in the solar system. Even on faraway Pluto, the coldest temperature recorded was minus 300°F, despite its being much further from the sun. Similarly cold regions were found at the bottoms of craters at the lunar South Pole in areas that were permanently shaded.
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