Perseverance: The Rover or The Trait?

On July 30th, Perseverance started its seven-month journey to Jezero crater, Mars, touching on Mars on February 21st, 2021. The Mars 2020 Rover Mission was started eight years ago, with Curiosity's landing at Aeolis Palus on Mars on August 6th, 2012. There are many missions that Perseverance will carry out, and there will be multiple firsts along with the mission. There are also multiple robotic and autonomous assemblies onboard Perseverance to help it carry out its numerous missions. The rover was developed at the Jet Propulsion Laboratory(JPL) in Pasadena, California, and will launch from Cape Canaveral Air Force Station in Cape Canaveral, Florida. This will be the fifth rover launched by NASA.

Perseverance at JPL

Perseverance first started development eight years ago, in 2012. At this time, it wasn't known what the exact payloads of the rover were going to be. Perseverance is very similar to Curiosity. NASA used many of the same instruments from Curiosity on Perseverance. Some returning instruments include the similar main camera mount and the power source, which is the multi-mission radioisotope thermoelectric generator (MMRTG). The MMRTG is very similar to a nuclear reactor and uses decay from a plutonium core to move electrons, causing electricity. 

However, there are still multiple improvements that happened to the parts that were adapted from Curiosity. One aspect that was changed was the wheels. The problem with the wheels on Curiosity was that they couldn't withstand the rocky surface on Mars, causing some of the wheels to rip and tear. As a result, Perseverance's wheels are built to be more robust and have a different tire pattern to make it easier for the rover to traverse the rocky surface of Mars. Perseverance also has a better drill to help cache samples more easily on the rover.

There are also multiple new instruments on the robot as well as some returning instruments. These include the Planetary Instrument for X-Ray Lithochemistry (PIXL), Mars Environmental Dynamics Analyzer (MEDA), Mars Oxygen ISRU Experiment (MOXIE), SuperCam, Mastcam-Z, Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC), the Mars Helicopter Ingenuity, two microphones, and 23 cameras. 

The Parts on Perseverance

As mentioned before, there are multiple missions, and first, that Perseverance is hoping to pull off during its time on Mars. Perseverance is hoping to collect more detailed samples of Mars's surface and drilling down into Mars to collect samples. Perseverance can hold between 20 and 30 drilled samples. Perseverance will do a multitude of things with these samples. It will use onboard equipment to tell the composition of the martian soil and determine if there is any form of life in the ground. Perseverance will also cache the samples in safe tubes and deposit them for the later collection so that NASA can test the samples on Earth. 

A first that is happening on Mars will also be the first powered flight on another planet. Perseverance's little buddy, Ingenuity, will do this. Ingenuity is a tiny helicopter stored in Perseverance's body until the rover lands on Mars. Then Ingenuity will take flight. Ingenuity is experimental, but NASA will use it to scout out locations on Mars for future missions. It can fly up to 90 seconds a day and is powered by a solar panel. It has a maximum altitude of 5 m and a top speed of 10 m/s. The helicopter is tiny and light, weighing in at 1.8 kg and having a volume of 15680 cubic centimeters. However, the rotors of Ingenuity are huge, measuring in at 120 cm and counting about 2400 rpm. 

Ingenuity

Now you may be wondering why so fast. This is because Mars's atmosphere is about 10% of the Earth's atmosphere. In other words, you would need a 100-foot wide parachute on Mars to carry out the same effect that a 10-foot wide parachute would carry out on Earth. This is a problem for any aerial motion, from landing via a parachute to lifting using rotors. This is also a problem when landing, as landing using solid rocket boosters are required to do this accurately. This period of landing is also known as the 7 minutes of a terror. This is when the rover is starting to land on Mars, from entering the atmosphere to safely touching down on the surface. It is a challenging and stressful period for everyone at NASA.

Apart from samples and Ingenuity, Perseverance will also carry multiple instruments to carry out experiments. One of these instruments is the Mars Oxygen ISRU Experiment (MOXIE). MOXIE will produce small amounts of O2 from the atmospheric CO2. This is very important because if we can produce O2, humans will use MOXIE capsules for breathing on Mars and create the central part for rocket fuel, liquid oxygen. Another instrument that Perseverance will carry is the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC). SHERLOC will use an ultraviolet Raman spectrometer to scan the surface and minerals on samples to detect any form of organic compounds. 

Perseverance will be landing at Jezero crater. Jezero crater was chosen as the landing site because there is evidence that there was a lake in Jezero crater billions of years ago. This is evident by the delta-like sand patterns and the entrance and exit streams from the crater. Scientists are hoping that they will be able to find signs of microbial life at Jezero crater.

Locations of Previous Mars Rover Landings

Before Jezero crater, multiple sites were being looked into as a landing site. These include Columbia Hills in Gusev crater, Eberswalde crater, Holden crater, Mawrth Vallis, Northeastern Syrtis Major Planum, Nili Fossae, and Southwestern Melas Chasma. 

Perseverance launched on July 30th at 4:50 am PDT.NASA launched it on the Atlas V-541 from Launch Complex 41. The launch window opened on July 30th and would have closed on August 15th, 2020. If the rover hadn't been able to launch during this period, we would have to wait 26 months till the next opportunity to launch Perseverance to Mars. The expected date of arrival on Mars is February 18th, 2021.

Atlas V Rocket that Launched Perseverance into Space

To land on Mars, Perseverance will be using a similar system to Curiosity, the Entry, Descent, and Landing System (EDLS), to ensure a safe landing on Mars. In the EDLS, the rocket will face its heat shield toward the atmosphere when first entering the atmosphere to protect the rover's chassis. Then it will deploy a parachute to act as an air brake and then disengage from the aeroshell to have a power landing, similar to Curiosity. All of this will happen autonomously in a matter of minutes. This period is also known as the 7 minutes of terror because it is very stressful.

In the end, Perseverance is one of the most complex machines of our time. However, with the Perseverance mission, the door to many other future missions will be open. These include building a "fetch rover" to fetch the samples that Perseverance will collect. This is expected to launch in 2026 and fetch everything by 2029 and return them to Earth by 2031. This also opens the door to bringing people to Mars, which is expected to happen in 2030. Perseverance is a rover that you can't miss out on watching, and it will change up what we know about and how we think about Mars.

Render of Perseverance on Mars

Sources:

“Jezero (Crater).” Wikipedia, Wikimedia Foundation, 23 Nov. 2020, en.wikipedia.org/wiki/Jezero_(crater). 

“Mars 2020.” Wikipedia, Wikimedia Foundation, 24 Nov. 2020, en.wikipedia.org/wiki/Mars_2020. 

“Mars Helicopter Ingenuity.” Wikipedia, Wikimedia Foundation, 22 Nov. 2020, en.wikipedia.org/wiki/Mars_Helicopter_Ingenuity. 

“Perseverance (Rover).” Wikipedia, Wikimedia Foundation, 20 Nov. 2020, en.wikipedia.org/wiki/Perseverance_(rover).