Mars rover ‘Perseverance’
Collection of 12 samples containing organic matter
When you return, you may find life in space.
The Danuri, which departed to the moon at 10.1 km/s on August 8, is flying at a speed of 0.1 km/s at a distance of 1.56 million km from Earth as of September 30. The expected arrival date of the moon is December 17th. Apollo 11 went to the moon in 4 days and 6 hours, but Danuri takes a lot of time because it uses the gravity of the sun and the earth to go to the moon. Since the moon orbits the earth, it is relatively easy to send a probe from the earth to the moon. However, Mars, like Earth, orbits the sun with each other, making it difficult to send probes. The Hohmann orbit is used to send probes from Earth to Mars. The Hohmann orbit is an elliptical orbit created between the Earth’s orbit around the sun and Mars’s orbit around the sun. In other words, the perigee of the Homan elliptical orbit is the Earth’s orbit, and the apogee is the orbit of Mars. All rovers launched from Earth to Mars follow the Homan orbit, and the flight time is usually 260 days. The problem is that you can’t start at any time. It should start when the Earth is at the perigee of the Hohmann orbit and Mars is at the apogee. When the Earth, Sun, and Mars are in a straight line, this is called an association period. The period of association between Earth and Mars is 775 days. It is created once every two years and 45 days.
Now, it is said that Musk’s SpaceX will use the large space launch vehicle and spacecraft ‘Starship’ to send people to Mars. How long would it take to travel to Mars by Starship? First of all, it takes regarding 260 days to get there. It would have to wait 445 days on Mars to return to Earth using the Homan orbit. To return quickly, it would take regarding 268 days to return to Earth through Venus following a 90-day stay on Mars. It has taken such a long time, so it is not easy at present to travel to Mars. However, Mars is the only planet in the solar system that humans can go to. The maximum temperature in summer is minus 5 degrees Celsius and in winter it drops to minus 87 degrees Celsius, but it is enough to live in a space station wearing a space suit. There is also a little atmosphere, so a small unmanned probe may use a parachute to land. It may be more convenient than the moon for humans to live for a long time. For this reason, Mars exploration is likely to continue in the future.
Chae Yeon-seok, Former Director of Aerospace Research Institute
So far, lunar soil and rock samples have been brought to Earth through the lunar exploration program, weighing 393 kg. However, no Martian soil samples have yet been brought to Earth. Currently, NASA and the European Space Agency (ESA) are jointly working on a project to bring Mars soil to Earth. The plan is to bring 500g of Mars soil samples to Earth at a cost of 9.79 trillion won, which started in 2019. First, the 1 ton ‘Perseverance’ Mars rover was launched in July 2020 and successfully landed on Mars’ ‘Jezero’ crater in February 2021. Perseverance carried a drone ‘Ingenuity’ with a weight of 1.8 kg and a wingspan of 1.2 m. This is to guide the perseverance to find a place to explore from above and to find the target well. Injury made its first successful flight from Mars on April 19, 2021. Perseverance, which has been exploring Mars in the meantime, secured four samples containing organic matter in July. So far, 12 samples have been collected. A titanium sample tube holds 20 g of igneous soil and rock samples.
The next step is to land the sample recovery rover developed by ESA on Mars in 2028, retrieve the Mars soil sample made by Perseverance, move it near the lander, load it on a Mars takeoff rocket, and launch it into Mars orbit. After docking with the Mars sample return ship orbiting Mars at a height of 300 km, the sample is moved and returned to Earth. So far, only the United States and China have successfully landed a rover on Mars. If all the plans, including the landing of ESA’s rover on Mars, were successful, even finding evidence of life in the Martian soil samples brought to Earth, it would be the most groundbreaking discovery since history.
Chae Yeon-seok, Former Director of Aerospace Research Institute
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