Following the respective landing of the “Curiosity” rover and “InSight” lander on Mars in 2012 and 2018, NASA launched a rocket between July and August 2020 to take the “Perseverance” rover to Mars for its “Mars 2020” mission. The science objectives include: seeking any possible signs of ancient life; trying to produce oxygen from the atmospheric carbon dioxide; collecting and storing samples of rocks and soil, etc. Moreover, the mission includes flying a robotic helicopter on Mars for the first time to demonstrate the technology of airborne scouting and to prepare for the exploration of other planets in the future.
The Hong Kong Space Museum staged a special exhibition at the foyer to review on past missions, to explore the red planet with special emphasis on the features, science goals and the latest updates of the “Mars 2020” mission.
A 360-degree panorama taken on Mars which composed of more than 1,000 images by NASA’s Curiosity Mars rover.
Credit: NASA/JPL-Caltech/MSSS
How similar are Mars and Earth?
Credit: NASA Visualization Technology Applications and Development (VTAD)
A little bit longer day A day on Mars is a bit longer than that of the Earth: a day on Mars is about 24 hours and 40 minutes. Seasons Earth has seasons because the Earth’s rotation axis is tilted relative to the orbital plane. Mars also has seasons, because Mars’s rotation axis tilts at an angle of 25 degrees.
How different are Mars and Earth?
Mind the boiling water Mars has a very tenuous atmosphere with pressure less than 1/100 of that of Earth. Liquid water above 0 degree Celsius boils on Mars because the lower the air pressure, the lower the boiling point. Keep warm Martian nights are extremely frigid – the temperature can be as low as -140 degrees Celsius.
Once upon a time, the Mars was…
Credit: NASA/JSC/Stanford University
Life on Mars?! Found in 1984, the Martian meteorite ALH84001 was suspected of containing microscopic fossils of bacteria. Though the idea of the presence of life on ancient Mars is still controversial, there are studies that suggested the possibility of life on the red planet eons ago. Other evidence suggests that Mars had a thicker atmosphere, or even oceans. A warmer climate offered a potentially habitable environment.
From rocks to climate
Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
From the isotopic ratios of drilled rock samples by Curiosity’s Sample Analysis at Mars (SAM) instrument suite, scientists suggested that Mars’ surface environment might have experienced a transition from warm to cold.
Find the water
Credit: NASA's Goddard Space Flight Center
Water is key to life. “Find the water” was the main theme of past Martian explorations. New geological evidence of past and present water encourages us to take the next step toward finding concrete evidence of life itself.
Mariner 4 :“Ladies and gentlemen, I am the first.”
Credit: NASA
Mariner 4 performed the first successful flyby of Mars. In 1965, it returned the first close-up picture of the Martian surface.
The first close-up picture of the Martian surface.
Sojourner: “This way, please.”
Credit: NASA/JPL
Landed on 1997, Sojourner was the first robotic rover to have ever travelled on another planet.
Spirit and Opportunity: “We found blueberries that are not eatable.”
Credit: NASA/JPL-Caltech
Spirit and Opportunity are a pair of twin rovers arrived in 2004. They are more advanced than Sojourner: equipped with panoramic cameras to picture the Martian landscape and help scientists studying the minerals in Martian rocks and soils.
Credit: NASA/JPL-Caltech/Cornell/USGS
Opportunity investigated the small spherules (nicknamed “blueberries”) found on the Martian surface. They may be water-related mineral precipitations or just remnants of meteorites.
Curiosity: “I love rocks!”
Credit: NASA/JPL-Caltech/MSSS
Landed in 2012 and still operating in July 2020, Curiosity read the history of Martian climate and geology by studying the chemical properties of soil samples drilled from rocks.
InSight: “Let’s see if there is anything special down there.”
Credit: NASA/JPL-Caltech
Landed in 2018, InSight is the first robotic explorer to study in-depth the “inner space” of Mars through its seismometer and heat flow probe. It is still going strong in July 2020.
Exploring Mars provides the opportunity to answer questions on the origin and evolution of life. The red planet could someday become a destination for the survival of humankind.
Objectives of Mars 2020 mission
- Identifying the habitability of the past Martian environments - Seeking signs of past microbial life - Testing oxygen production from the atmosphere - Collecting and storing the Martian rock and soil samples for potential return to Earth
The Mission
Mission Name: Mars 2020 Rover Name: Perseverance Date of Launch: 30 July 2020 Launch Location: Cape Canaveral Air Force Station, Florida, the United States Landing: 18 February 2021 Landing Site: Jezero Crater Mission Duration: At least one Martian year (about 687 Earth days)
Key science instrument Mastcam-Z
Credit: NASA/JPL-Caltech
Mastcam-Z (Mast-mounted camera system) can take high-definition video, panoramic colour and 3D images of the Martian surface. Its zoom lens can magnify distant targets and study features in the atmosphere. Its keen “eyesight” can also help scientists to pick out those rocks that might have preserved signs of past life.
Key science instrument MOXIE
Credit: NASA/JPL-Caltech
MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment) is a technology investigation that will produce oxygen from Martian atmospheric carbon dioxide. It will demonstrate how future explorers might produce oxygen from the Martian atmosphere for propellant and breathing.
Get to Mars
New landing technology: Terrain Relative Navigation
(1) Take descent photos (2) Compare to orbital map (3) Divert if necessary
Terrain Relative Navigation improves the chance of safe landing: during descending, the rover will take pictures of the approaching surface and autonomously compare them with the maps in the database. If any hazard presents, it will immediately divert itself toward safer ground.
To study Mars, we cannot bring room-sized equipment there. How about bringing samples from Mars back to the Earth? For the first time in history, Perseverance will collect and seal rock and soil samples that could be returned to the Earth by a future mission for intensive analysis.
Step 1: Collecting the samples Once scientists identify a rock target of interest, with a titanium tube for the sample, the rover’s drill penetrates about5 cminto the target. Each sample has a mass of about15 gand the plan is collecting 20 different samples at least. Step 2: Sample sealing and storing onboard Each sample will be sealed in a 14-cm titanium tube individually. These tubes will be stored inside the rover until reaching the decided time and place for drop off. Step 3: Depositing the samples on the surface The sample caches will remain on the Martian surface, awaiting potential pick-up by a future mission. Images taken by Mars orbiting satellite can identify the samples’ locations with a precision of about1 m.
Take off from the ground
Credit: NASA/JPL-Caltech
The mission includes flying a robotic helicopter, “Ingenuity”, on Mars for the first time to demonstrate the technology of airborne scouting and to prepare for the exploration of other planets in the future.
