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  • Mars is our next-door neighbor, and yet... we almost never visit.

  • We sent the InSight lander in 2018, an orbiter and lander combo in 2016, and two orbiters

  • before that in 2013.

  • Basically one or two missions every couple of years or so.

  • But in July of 2020, humans are launching four separate missions to Mars.

  • What is going on up there?

  • Why all at once?

  • Is there some incredible black Friday sale going on or something?

  • Sadly, nono amazing TV deals are to be had on Mars.

  • But the July 2020 launch window does offer great savingson rocket fuel.

  • The reason all these missions are launching then is because that is the ideal time to

  • get a craft to Mars while using the least amount of fuel.

  • But it’s not when the two planets are at their closest, as you might expect.

  • The most efficient way to send a spacecraft to Mars is using something called a Hohmann

  • Transfer Orbit.

  • This orbit is elliptical, and uses the sun as one focal point.

  • The spacecraft’s launch is at the closest point to the sun, or perihelion, and it crosses

  • Marspath at its farthest point from the sun, or aphelion.

  • It is very important, I cannot stress this enough, that Mars is actually there when the

  • spacecraft arrives.

  • No duh, right?

  • But for that to happen the spacecraft has to be launched at just the right time.

  • The time it takes a spacecraft to travel from perihelion to its aphelion in Marsorbit

  • is about 259 days.

  • During that time Mars will move about 136 degrees, since Mars is farther from the sun

  • than Earth and takes longer to move the same angular distance.

  • So in order to sync up the 180 degrees the spacecraft will travel while Mars moves 136

  • degrees, the spacecraft needs to launch when Mars has a 44 degree head start.

  • This happens for a few weeks once every 26 months, and the next time it will happen is,

  • you guessed it, mid-July of 2020.

  • And this time around a lot of space agencies are geared up for launch.

  • First up, with a scheduled launch window of July 17th to August 5th is another Mars Rover

  • from NASA, named Perseverance.

  • The latest car-sized bot is landing with the goal of searching for signs of microbial life,

  • and determining if Marsenvironment was more hospitable to it in the past.

  • It will also collect and cache samples of rock and regolith, and test oxygen production

  • in the atmosphere.

  • The rover will also touch down with an autonomous helicopter on board.

  • That’s right: it’s bringing a drone to Mars, though this one is specially made for

  • the thin Martian atmosphere.

  • It will carry no scientific instruments; its only goal is to test if this is an awesome

  • or dumb idea.

  • Next on the docket is a joint mission from the European Space Agency and Russia’s Roscosmos.

  • The mission’s rover, provided by ESA, is named Rosalind Franklin, after the pioneering

  • English chemist and x-ray crystallographer whose work was instrumental in discovery of

  • the structure of DNA.

  • She basically took a picture of the double helix.

  • Franklin died unrecognized for her contribution in 1958.

  • It’s good to see her get a nod from ESA more than 60 years later.

  • Rosalind Franklin (the rover) will explore what scientists think may have been an ancient ocean.

  • Like the NASA mission, the rover will search for signs of life past and present.

  • It will use a camera attached to a drill to study the soil it brings to the surface and

  • I can’t think of a much better tribute to Rosalind Franklin than a camera searching

  • for signs of life on another world.

  • Finally, the remaining two missions are important milestones for two different space agencies.

  • The United Arab Emirates will launch its Hope orbiter sometime in July, with the goal of

  • studying Marsfading atmosphere.

  • If it goes as planned, the UAE will claim the title as the first Arab nation to send

  • a spacecraft to Mars.

  • China is also planning to send an orbiter and rover combo named HX-1 to Mars.

  • This will be their second attempt, after their first Mars orbiter was stranded in Earth's

  • orbit and then destroyed by our atmosphere back in 2012.

  • With this stellar lineup of missions, July 2020 will be an exciting time for Mars exploration.

  • Hopefully all goes as planned, and 259 days later well have a new squad circling the

  • red planet and kicking up regolith.

  • Because if not, we have to wait 26 months for another shot.

  • And you thought waiting a year between TV show seasons was hard.

  • ESA and Roscosmos’s mission is launching in 2020 after missing its original planned

  • window in 2018 due to technical setbacks.

  • The 26-month wait has helped make this summer one of busiest seasons of Mars launches yet.

  • Thanks for watching.

  • If you want more Mars videos, check out this one I did on why the Mole on NASA’s InSight

  • lander can’t seem to burrow beneath Marssurface.

  • Be sure subscribe, and I’ll see you next time on Seeker.

Mars is our next-door neighbor, and yet... we almost never visit.

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2020年的火星競賽 (The Race to Mars in 2020)

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    林宜悉 發佈於 2021 年 01 月 14 日
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