So you want to travel to Mars? Watch out! | Dr. Jingnan Guo | TEDxKielUniversity

well who has ever gent to go to space one day hands up most of us and to Mars where me too and that's actually why I have been studying astrophysics since I entered University and who knows what kind of danger they are in space for example bone losses and like a gravity that may cause back pains muscle pains and your hearts have to pump and no gravity so in my have issues some may have the psychological problems being away from their fair and parents from the families and friends what is radiation and in fact radiation is the one risk that persists after landing after returning back to earth because it may be cancer causing in a long term radiation interacts with our DNA molecules either directly or through ionizing the water molecules inside your body and this will generate free radicals that can further interact with the DNA chains and this actually happens inside our body all the time but it doesn't do us any harm most of the time because the radiation doses is very low during the daily life in fact we're living a world full of radiation it is even in our fruit bananas for example it is rich in potassium and potassium forte is naturally radioactive well but don't stop eating bananas because potassium is also important for our body for organs function properly some are quite scared of going to the doctors for medical x-ray checkup but how many banana doses do you think is equivalent to one dental x-ray any guesses fifty banana doses so about the banana you eat in two months time and well in fact taking a flight may also increase the radiation intake so next time when you go to New York from Hamburg to visit your best friend if you have one and you the radiation dose equivalent to your journey would be about 500 banana doses that's about ten dental x-rays but because of the food we eat because of the world we are living in we ourselves are actually radioactive yes indeed because we have potassium-40 carbon-14 inside us and that makes it redirect saving the night when you're cuddling your beloved ones in bed no so when you're sitting here next to each other but don't panic and please don't run away this level relation wouldn't do any harm to our bodies because our cells are constantly self repairing or even in some cases when they die our body can replace the cells that that says easily and this is not doing any harm to us but for the ones who raise up the hands that wanting to go to space the radiation level in space is much higher because of these guys visit supernova explosions they're the most powerful explosions of a dying star and this can send off the shockwaves that can accelerate particles with different charges to very very high energies and this highly charged and energetic particles may interact with our DNA molecules and cause mold damage and here you see the difference between a normal x-ray and the charged highly charged particle interacting with a DNA molecule just imagine this instead of shooting a castle with a shotgun you're actually bombarding it with a cannon and the power caused by this this highly charged particle is much more permanent and the damage is much more severe and can be cancer causing and these particles they can travel through space they can travel through interstellar space and eventually reach our solar system but what happens in the Sun has its own magnetic field that is basically filling up this whole heliosphere this hailey sphere with its magnetic field is deflecting away and shooting away a large portion of such galactic cosmic ray particles and this is very effective what is even better for us living on earth for us sitting in this room in that the earth itself has its own magnetic field and this is generated by this superheated swirling iron coal that is three thousand kilometres and then is my feet and this movement generates the electric currents that induce this global magnetic field of the earth that can shoot away most of the galactic cosmic ray particles also the earth has its atmosphere which is a very effective shielding layer as well and that is why we go higher with an airplane you have more radiation dose intake because you have less atmosphere on top of your head as protection but if you go so much higher that you end up outside Earth's magnetic field end up in space you exposed the ret directly with this impinging galactic cosmic ray particles not only that the Sun can be very naughty sometimes the Sun has all sorts of exploding solar storms all energetic particles and this is can also be damaging to the to our DNA is up there so in any case space is not of relation friendly environment and now we ask for the ones who want to go to Mars how about the situation on Mars does Mars also have the protection at earth does the answer is unfortunately no look here earths has its magnetic field shooting away this energetic charged particles but Mars only have these little blobs of magnetic field it's very weak and various localized and it's actually the fossilized magnetic field that's left over from ancient Mars magnetic dynamo which had died out long time ago unfortunately and it's actually going to be the future of Earth by the way and lack lacking the magnetic field and also lacking a good thick protection of the atmosphere Mars is very fragile against the space radiation so going to Mars is probably not going to be beneficial for your long term hairs but why after all what happened telling you after all these threatening and the risks of traveling to Mars we're still trying the scientists are still trying hard to make it possible for man missions to Mars now why to Matt Damon and his team want to go to Mars the answer is simply because they can Mars is our neighbor planet considering the orbit of the two planets around the Sun it takes only about 500 days going in return and you have to stay for about 400 days for good connection to come back and the total duration is only about 900 days and this is nothing at the space nation mind you the Rosetta took 12 years to meet a comet and this is totally doable not only that Mars has a environment that is quite similar to some places on earth look here I've got two pictures one is taken on surface of Mars in Hawaii Morocco who thinks the right one is taken on surface Mars hands up and who thinks the left one instead is on Mars whoa moon people effect the right one is taken on surface of Mars by curiosity lately the left one is in Morocco but they really look alike so if one day we ever wanted to if I wonder you ever end up on Mars you wouldn't see something that is completely different to you and also during the day the temperature can be good 20 30 degrees during the daytime but one of the most one of the most significant differences you would expect is the surface radiation as I explained you but what exactly would level of radiation there on the surface of Mars was unknown and to only three and half years ago until when curiosity landed this is a photo of the Curiosity rover before it was launched in November 2011 it has many scientific instruments on board and here on shoulder right shoulder it fits our nice little particle detector which has the size of a large cappuccino Cup American size know your PIN size and this cappuccino cup is sending us data as we speak right now from the surface of another planet and this is the first time in human history and with this data I have been looking at the relation environment on surface of Mars for three years and a half and I have been looking at this data Moe and Moe that I learned that radiation on surface of Mars is very complicated it is much more complicated than we thought ere I plotted 500 days of radiation data on the surface of Mars measured by two different sensor heads of the detector as you can see that the data varies a lot and this is caused by several factors if you zoom in to just a few days of data you would see that it also leads day and night these are not the Martian aliens these are caused by the pressure change on the surface of Mars because we have another pressure since a head on the rover we can see the pressure data it also leads day and night at Gale Crater up to 10% this pressure change actually is varying the shielding effect of this very thing atmosphere on Mars and the same thing happens at a seasonal level because Mars have this icy carbon dioxide polar cap and this will change the pressure during the summer and winter and this will also contribute to the long term variation of the dose rates we mirror but what is mostly dominating in the long term is a solar modulation what does that mean it means that yes the solar magnetic field the Heliospheric magnetic field is acting as a shooting in fact towards its incoming galactic cosmic ray particles but this is not constant neither in time no in space the heliosphere is very dynamic and it varies a lot from different location to location and the Sun has all sorts of activities changing the hill aspheric magnetic fields this is driving the evolving constant evolving of variation of the radiation dose on Mars and also you see the spikes here these are the direct solar events heat Mars and being seen by all radiation detector so these are really a lot happening on the surface of Mars so for the ones who are do thinking to go to Mars for your next holiday this is my Martian travel guide for you The Sun has 11-year solar cycle go there during the solar maximum when a solar magnetic field is strongest you'd get most protection from the solar magnetic fields against the galactic cosmic particles but please watch out those dangers all events and scientists space scientists can provide you this space weather forecasts because we have mounted spacecraft observations complicate modeling so they can tell you when there's a solid vent coming and where it is heading to and what kind of energies you expect to see and in this case you can hide into your urgent chatter inside your spacecraft to go through this sullivan times when you're actually on the surface of mars maybe you can seek the soil the surface soil as a protection basically the deeper you go the more protection you would have from above your head as shielding against the galactic cosmic Parkins and also Sullivans and when you're actually there send me a postcard and lots of data there will be the best gift for me thank you

Channel: TEDx Talks

Views: 53,140

Keywords: TEDxTalks, English, Germany, Science (hard), Physics, Science, Space, Travel

Id: QBi8BTK71Mk

Length: 15min 51sec (951 seconds)

Published: Sun Jan 03 2016