Planetary Society Deploys LightSail 2’s Solar Sail. What Does The Future Hold For Solar Sails?

Planetary Society Deploys LightSail 2’s Solar Sail. What Does The Future Hold For Solar Sails?


where you can travel in space depends on
how much propellant you’ve got onboard your rocket and how efficiently you can
use it but there’s a source of free propellant right here in the solar
system the Sun which is streaming out photons in all directions you just need
to catch them and right now the Planetary Society’s new light sail 2
spacecraft is testing out just how well it’ll work solar sails are an ingenious
idea that were first thought of by johannes kepler back in the 1600s as he
imagined that sails and ships could be adapted to space travel of course he
didn’t fully understand the physics involved yet but with major discoveries
in particle physics and quantum mechanics in the early 20th century
scientists realized that light itself could act like a wind that blows a sail
in space although photons have no mass they can impart momentum when they
bounce off a highly reflective surface this is a light sail it’s not very much
but in the vacuum of space there’s no air resistance to slow down the sail
with enough photons and enough time a light sail can accelerate to incredibly
high speeds using a chemical rocket you could convert the entire mass of the
observable universe into rocket fuel and you couldn’t get a small spacecraft
going faster than 0.2% the speed of light but a light sail can theoretically
take you up to relativistic velocities traveling from star to star in human
lifetime since unlimited free propellant comes from the Sun and huge velocities
are possible why are there solar sails everywhere good question it’s a question
that the Planetary Society has been obsessing about for years and they’ve
launched a solar sail to try to figure out how well they actually work back in
2005 they tried to launch the world’s first solar sail cosmos one but rocket
failure destroyed it then they went back to work developing light sail one which
was launched in 2015 and successfully tested their solar sail
deployment in space and finally in 2019 the Planetary Society was ready to
actually try sailing in space on June 25th 2019 a SpaceX Falcon Heavy blasted
off from Florida’s Cape Canaveral carrying 24 spacecraft for the US Air
Force’s step2 mission this was the third time the Falcon Heavy had been launched
and we were all hoping it would successfully land it’s middle stage not
so much that’s still on the to-do list but that’s how what this video is about
anyway in addition to the mysterious Air Force satellites Falcon Heavy was
carrying the planetary society’s light sail to onboard its procs one carrier
spacecraft which are released at an altitude of 720 kilometres then on July
23rd 2019 the spacecraft deployed its solar sail it opened its hinged solar
arrays and then unreeled for tape measure like sail booms reeling out its
four triangular sails deploying 32 square meters of sail area it’s
important to note that this spacecraft is tiny with a weight of just 5
kilograms or 11 pounds about the size of a loaf of bread as it orbits around the
earth the spacecraft swings it sails into and out of the sunlight with each
period raising its orbit by a few hundred meters a day that sounds great
unfortunately light sail too doesn’t have the control systems on board to
control its angle carefully enough to remain in orbit indefinitely while it’s
raising its orbit on one side of the earth by several hundred meters a day it
can’t tilt the sails precisely enough to prevent lowering its orbit on the other
side of the planet eventually it’ll dip into the Earth’s atmosphere and burn up
but hopefully engineers at the Planetary Society will have finally learned how
practical a solar sail can be for space exploration it’s still in orbit at the
time I’m recording this video and sending back awesome pictures of our
home planet and I’ll put links in the show notes where you can download them
and turn them into your new phone wallpaper thanks to the Planetary
Society we’ve got their test of a solar sail arthur c clarke would be pleased
but there are some other interesting ideas for solar sails of the future and
i’ll get to that in a second but first I’d like to thank Denis Dattilo Ron
Stowe Brian gray the giant nothing and the rest of our 796 patrons for their
generous support they contribute so that you can see these videos and we can make
them freely available to anyone who wants to learn about space join our
community at patreon.com – universe today and get in on the action with the
Planetary society’s light-sealed – sending home data teaching mission
controllers to sail in space these will be valuable lessons for future missions
that might use this technology as an actual method of propulsion one mission
in the works is NASA’s near-earth asteroid scout or Nia scout this CubeSat
mission could fly as a secondary payload with the first test of NASA’s Space
Launch System the uncrewed em1 mission which could launch as early as June 2020
after deploying from the Orion capsule neoscope would unfurl its solar sails
twice the size of Lights Hill – and then spend two years traveling to a
near-earth asteroid to study it up close we don’t know the target yet but a
potential destination might be the near-earth object 1991 VG which was
discovered in 1991 shortly before it passed about the distance from the earth
to the moon away from us and they came back in August 2017 we’ll want to keep
an eye on this rock as a potential threat but also as a treasure trove of
metals and minerals that could help support future exploration of the solar
system another mission that could use a solar sail as Japan’s oversized kite
craft for exploration and Astronautics in the outer solar system or Okeanos
this would be a mission to the Trojan asteroids which are located at the l4
and l5 Sun Jupiter Lagrange points these are an ideal place to study asteroids
because Jupiter and the Sun’s gravity have trapped a large number in one spot
and a mission can easily sample many different asteroids Okeanos would have a
hybrid solar sail covered in solar panels which
all to use to provide electricity for its instruments and ion engine Japan was
one of the first countries to ever test a solar sail with their ocurro’s mission
which was deployed in 2010 and eventually gained hundreds of meters a
second of velocity using a solar sail Okeanos might even come with a lander
thanks to their experience with Hayabusa – and asteroid ryugu JAXA has learned a
tremendous amount about landing and collecting samples from tiny asteroids
if all goes well okay uh notes we’ll launch in the mid-2020s onboard an h2 a
launch vehicle using several gravity assists to make the journey out to
Jupiter and if the mission is really successful it might even bring a sample
of a Trojan asteroid home NASA is even considering adding a solar sail to the
deep-space lunar gateway at a special planning event for the deep-space
gateway in 2017 members from the Canadian Space Agency presented the
concept of a solar sail that could be added to the station the ongoing light
from the Sun would provide a constant thrust that the station could use to
maintain its orbit without propulsion held out on a Canadian robotic arm what
else a 50 square meter solar sail could save the station nine kilograms of
hydrazine a year which is expensive to carry up from the earth to the moon one
mission that you’re probably familiar with is the breakthrough starshot
concept instead of using light from the Sun as propulsion breakthrough starshot
hopes to use powerful lasers which will accelerate tiny satellites to
interstellar velocities these could be the first spacecraft that ever sent home
images from another star system and we’ve done a whole episode on this and
another heavier laser sail mission called Project dragonfly and I’ll put
links to these episodes in the show notes
unfortunately it’s taken longer for space agencies to incorporate solar
sails into their missions than I would have hoped it’s understandable they’re
complicated and fragile and require precise orientation it makes sense that
mission planners would use tried-and-true chemical rockets or
efficient ion engines to propel their spacecraft across the solar system but
as more and more solar sails are launched and tested engineers will
become more confident at the best ways to use them
as part of a mission I can imagine future when almost every
mission has a backup solar sail onboard just in case something goes wrong with
the main engine I’ve always been fascinated by the possibility of solar
sailing and I’ve watched each discovery and step forward with excitement
I’m really glad the Planetary Society has made it this far with their tests
they did the entire mission for 7 million dollars
funded by Planetary Society members private citizens and a Kickstarter
campaign so if you want to support this in future missions to help explore the
solar system go to Planetary org and find out more what do you think limitary
thoughts in the comments once a week I gather up all my space news into a
single email newsletter and send it out it’s got pictures brief highlights about
the story and links that you can find out more go to University datacom slash
newsletter to sign up and did you know that all of my videos are also available
in a handy audio podcast format so that you can have the latest episodes as well
as special bonus material like interviews with me show right on your
audio device go to Universe Today Viacom such audio or search for Universe Today
on iTunes Spotify or wherever you get your podcast and I’ll put a link in the
show notes and finally here’s a playlist

100 thoughts on “Planetary Society Deploys LightSail 2’s Solar Sail. What Does The Future Hold For Solar Sails?

  1. Wow, the fact that they were able to send anything into orbit for 7 million dollars is an amazing feat itself.. I didn't pay attention at the beginning, were they piggybacking on another mission or was it 7 million total?

  2. Fraser, love your videos. If space is a vacuum and no air resistance why do we need to make sure a space craft has sufficient thrust for extended periods of time? Wouldn’t just one “push” at the beginning send it on its way forever (theoretically) ? Thanks!

  3. Building up a lot of speed is great, but what would keep me awake at night while i travel on a ship making use of sails from star to star is the thought of the solar resistance met upon arrival at the destination not being sufficient to provide enough deceleration.

  4. Since ion engines work on compounding thrust, and solar sails work on compounding thrust, could they be used together for missions to achieve higher velocities, or am I misunderstanding something?

  5. Can solar sails work off reflected light (ie, the moon) or, say, Jupiter? Or does only the sun put out enough particles for the solar sail?

  6. what do you think of this as the most realistic interstellar craft we can build using current technology…. Very large solar Sail Craft, with a living space that has a large rotating section or sections. powered by a powerful reactor.

  7. Hey Fraser, can you do an episode on dipole sails ?

    https://www.centauri-dreams.org/2018/06/29/the-dipole-drive-a-new-concept-for-space-propulsion/

  8. Was waiting for IKAROS to come up. With all due respect to the planetary society they're late to this party

  9. Hey Fraser, love the videos, I have a question: if space is bone chillingly cold, how does hot gas like from a planetary nebula stay at such high temps? You would think just being in cold space would cool it off fairly quickly.

  10. 1:09 Is space truly a vacuum, nothing at all? With all the area this sweeps as it goes faster & faster what is the drag?

  11. If a sample of an asteroid or Mars were returned to Earth and found to have life on it, and it was proven that it wasn't just contamination, would we have to return the sample back to its homeworld? How will we deal with alien bacteria should they be discovered?

  12. Hey Fraser I have a question . How large are the LaGrange points? The stable area of it has to be much larger than a literal point. I believe you said points 4 and 5 are the most stable, if you put an object near the edge of one of the LaGrange points but still Within, will it still be stable? Also, how great was the Mass Effect Trilogy? Pretty dang great I would say.

  13. Anton from what da math just talked about a paper which suggests that theia may have deposited all of our water when it impacted and created the Moon. The paper suggests that the object was 10% the size of Earth but the Earth is 70% water. That math doesn't seem to be adding up to me

  14. Hi Fraser, a question about the moon: Which of these images is an accurate representation of viewing the Earth when you're standing on the moon? Image 1: https://external-preview.redd.it/cQTITiNkxLgd5xyGL8Nmumllo71oS_I2Dme5YOQGtZ4.jpg?width=640&crop=smart&auto=webp&s=d83ccb204df406fb0bdfb0afb14371bc0e2361ba Or image2: https://img.posterlounge.co.uk/img/products/450000/441328/441328_poster_l.jpg Thanks.

  15. Solar sails are one of those concepts that is so awesome, it's almost inevitable that it will be a thing one day.

  16. For me , Solar Sails will take time to become effective but i like both Sun and Laser acceleration used for acceleration .

  17. Asteroids/Moons will be very useful in future to build satellites , equipments , machines , probes in space itself so that we don't have to carry much in space from earth altogether and It'll soon happen I believe .

  18. I think we should deploy more into Moon's research , our moon and other planets Moons which possibly can support some form life like Europa etc. Our Moon can be efficient base to launch .

  19. This topic is really interesting. I’m impatient to seeing what the final results will be for this spacecraft.

  20. I don't understand. Photons and charged particles from the sun radiate out in a straight line directly away from the sun and they don't "bounce" off a solar sail like the wind does on a watercraft. This means you can't "tack" like a sailboat does on the sea. I'm thinking that re orienting the "sail" on the spacecraft will only change the speed of the spacecraft, not cause it to change course. What am I not seeing?

  21. to set the context, let's say some thing or assembly of things were traveling straight towards earth either faster than light or through a wormhole as to expedite its distance to us faster than light. if we were to be observing it with a telescope the entire time what would we see? would it look as though its relative time was at some astronomically multiple of our percievied time when moving faster than the speed of light? would it appear to teleport in time had it gone through a wormhole since it's now in front of the light of the "past"? would we then see it in the "past" after it arrives to earth? I appreciate the consideration of response and moreso an actual response if you see this. ♥

  22. If you want to know who is going to be on a manned mission to physically unfurl a solar sail then check out this photo: https://www.flickr.com/photos/suitable4framin/19964975733 #2pac

  23. For deploying a large low mass/area mirror in space I came up with inflation insituform in which the structure is made of materials that either harden or degrade on exposure to UV. It can take launch forces and then inflate and harden while shedding parts needed only for launch protection and inflation. Would be perhaps useful for solar sails. Obviously the problems with the James Webb drive me crazy.

  24. The number 1 problem with solar sails is not their very low acceleration, but the nonexistant deceleration. Its always going to be a one-way crash mission cos there is no way to "sail" back home. You cant just turn around the sail. Maybe they carry extra propellant for the journey home, or beam back their data, or do complicated gravity assists. However, gravity assist methods take a long time and will still not be enough to get the craft home. The solar energy also gets exponentially weaker the further you get away from the Sun, so you would need bigger and bigger sails the further you want to travel. They might be ideal for Voyager type missions, but not for boosting SLS or ISS, cos they will need gigantic solar sails whose weight will be more than just using propellants. Just my few thoughts people, Im not trying to throw shade at the sails lol 🙂

  25. All passive systems are impractical for human use. They're too slow and they always will be. By the time solar sails are ready fusion, ion, electric sails, etc will be advanced enough to go much faster much quicker

  26. Correct me if I'm wrong, but doesn't e=mc squared imply that photons do indeed have mass?
    re: 1:00 "Although photons have no mass…"

  27. When you say "can launch it at Interstellar velocities," do you mean that it will go as fast as Matthew McConaughey, or as fast as Jessica Chastain?

  28. I remember giving a very modest contribution to the first Planetary Society attempt, then life became complicated…. Thanks for the update, and reminder of their good work. I think a, belated, membership renewal is in order.

  29. Solar sailing is such a romantic and economic way for space exploration. We need to make it practical.

  30. https://youtu.be/mrjpELy1xzc Hello,do we need this much rocket to reach Mars in single stage? Is this rocket launch animation Video legit?

  31. Hi Fraser, I thought of a simple way you could explain Dark Matter. Imagine a phonographic record, with deep grooves, and marbles being free in those groves. Gravity is if you push all of those marbles at the same force, in the same direction. Dark Matter is like turning on the record player, and the outer marbles will seemingly go faster, and travel most the distance. In outer space this could be the Dark Matter moving, like the record. Or it could be a force that is pushing the record, sort of like a hand pushing the record around. Could it be that Dark Energy is adding that force causing the pressure, we detect as Dark Matter?

  32. Great video, I too see great promise with sails doing good things in the realm of space exploration. Culminating in the exploration of other stars, and finally the one thing all of us plebs could get a little glimmer of hope in someday having/ our own personal mini sail ship, yep that's right-we can dream, i owned a sailboat for years/this would be a great lvl2/ Star Trek anyone? They had a personal solar sail craft in i believe deep space 9? Anyhoo, thanks for the vid, Planetary Society getting things done/the future is bright.. -Cheers

  33. I'm looking forwards to Cody's lab dosing him self with mars level radiation. that show you and Pamela did on that topic was a serious misrepresentation of the papers from Nasa you claimed to be talking about. Science educators who just make shit up are worse than useless. How long did it take Pamela to work out she can't ski jump to escape velocity off Pluto?

  34. You say that if you converted the entire Universe to fuel you could not get a small spacecraft upto 0.2C!, that is simply incorrect, it would be quite easy in fact, assuming a space based launch.

  35. Lasers strong enough to propel a craft to interstellar speeds having to go through the atmosphere… Can't imagine that being a long term project. Let alone the amount of energy you would need for every launch.

  36. Actually the first ever solar sail was deployed by the russians during the mission Znamya 2. But at that time they restructed their sail into some kind of mirror to reflect sunlight onto earth. But the constructure was absolutelly 100% a sail prototype.

  37. Could make enough solar sails big enough to block the sunlight hitting Venus cooling it down and in the mean time get enough power to do it

  38. What really grinds my gears is that we'll literally never know the level of technological development that humanity has truly reached within black budget military projects. Money, resources, and ethics are not problems at all at that level of fuckery.

  39. Does the moon gravity disturb the satellites and space telescope deployed at L1 and L2 lagrange point??

  40. Hey Fraser

    will the interplanetary space ever be cleared of dust? is it a matter of time or is dust always added?

  41. does the Solar Wind help? protons from the Sun must have more energy than photons and almost as continuous? Perhaps they may damage the sail but there is no turning them off.

  42. The sun can also be used for attitude control. Mariner 10 demonstrated that way back in 1974. https://solarsystem.nasa.gov/missions/mariner-10/in-depth/

  43. Using a solar sail is only good for one way! But even for a round trip, it would cut the cost of fuel and fuel containment in about half!

  44. Hello Fraser,
    I have few questions that i would very much like to see you make a dedicated video, with more info than just a Q&A.
    I am fascinated by earth like planets, but i can't find proper videos considering my questions, i think there are no videos, because it's very tricky to make such a video in answer to those questions.

    Here are my questions:
    1. How many planets have we found, that are in the goldilocks zone around their suns ?
    2. How many criteria are there for a planet to be called earth twin ? (Can you provide list ?)
    – I am not talking about planets like Kepler-186f that people call second earth. Just the fact it's most likely tidally locked should make it fall out from the list. I mean planets that are exactly like our earth.
    3. How many of those criteria can we confirm from earth and how many we can confirm only after sending satellites to those planets ?
    4. How many of those planets that are in the goldilocks zone have all the criteria that we can confirm from earth ?

    In short, let's say we have 5000 planets in the goldilocks zone, and there are 36 criteria for a planet to be called earth twin, and we can confirm only 25 criteria from earth and 11 we can confirm only after sending a satellite. So any idea how many planets have those 25 criteria ?

    I know it's a tricky topic.. but can you answer ?

  45. Solar sails will probably only realize their full potential when we get space based manufacturing but advancing the technology has so much potential as photons are basically the best possible propellant traveling at c itself!

  46. If neutron stars can crush protons into electrons and form neutrons, is it possible to split neutrons into protons and electrons?

  47. Hey Fraser,
    I am a big fan. So everyone knows that all distances in the universe are based on the redshift of all objects. My question is how do they know how much of a shift equals a certain speed of recession? I have never seen it explained anywhere, and I am sure they are right, but I would like to know how. Thanks

  48. I am still waiting for someone to send a lightsail to the sun, unfurl the sail and see just how fast it could be by the time it passes earth. It would be an excellent example of acceleration and control to changing direction, etc, during the mission. It would answer questions regarding how to change course while in mid flight, etc.

  49. I think that the Planetary Society is a good place to donate money to. I wish they were more politically neutral but still, they're doing a lot of good advancing science for all.

  50. I hate to point out the obvious…. sure you can travel far at great speed, but how do you slow down? Please don't say "by flying directly into photons of the other star" All

  51. I love this concept! Can we potentially use solar sails for sending capable orbiters, landers and rovers to Mars, Europa, Ganymede, Titan, Enceladus, Triton etc. ? May be combined with Ion engine for outer solar system destinations. What about Magnetic Sails … any upcoming experiments on that?

  52. Good day Mr. Cain! These LightSails got me thinking about the Oort cloud surrounding our solar system and how they would have to navigate through it if we would want to reach another star. Do all solar system have Oort clouds or is that unique to ours? Also, Is there a way to know if the Oort cloud was a single planet or multiple destroyed ones. Thanks!

  53. I have been excited about the Breakthrough Starshot concept for a while. The idea of sending any sort of craft to an interstellar target, and receiving return data (and pictures!) in my lifetime is a heady one. However, my question is, if the proposed craft are only a few centimeters in size (minus the light sail, of course), how are they going to have a powerful enough antenna and transmitter to get an intelligible signal back to Earth from light years away? I read the proposed camera resolution would be about 2 megapixels. Can you imagine how long it would take to receive a single image at the rate of one (hopefully) error corrected bit every ten minutes! Also, with such a small size, any onboard camera is going to have a very small aperture and sensor size, making it really no better than a cell phone camera, suffering from the same fundamental design limitations that require ever more post processing (read: making up fake detail to fill in the missing or faulty real information)

  54. With a sail of this size the aerobreaking at very high altitude would be significant. I wonder if it will parachute down rather than burn up.

  55. First a space raft (Apollo 11) now a space sail. Yeah I think we are on the right track for deep space exploration, like say higher orbit? To me real space exploration and real space ships are something like you already past pluto and you remember you forgot you glasses and come back to earth to get you glasses and resume the mission without any issues whatsoever. That's real capability in space exploration.

  56. Why did you say all the matter in the universe if used as rocket fuel couldn't propel a rocket faster than 0.02%C? Gravity of the fuel alone would stop time lol. What about a nuclear powered ion drive, that would match the sail I think, no?

  57. Thanks! "Our chief engineer is trying to deploy a makeshift solar sail. We have high hopes that this wiII, if successfuI, generate power to keep us alive." [Star Trek IV] I'm one of those who vehemently believes in the idea of including multiple options for powering a spaceship – particularly a manned one. It is absolutely vital that astronauts (or whatever we call them when they're shooting around the Solar System!) have things to work with & to choose from. Me? I'd want a Mr. Fusion at the back of that thing! Sure – throw in some banana peels! I've been feeling a bit sorry for myself lately, in that – even though we are finally venturing into space now (better late than never, I suppose) – it's going to take a while. People who want to go to Mars first – bypassing any hope of learning survival skills on the Moon first – are loud enough that even if they don't win, they'll delay the whole process. I was born in '65, and I'm keenly aware that we should already be there*. But that can't be helped now, of course. And while I will get to watch us take these first few (if belated) baby steps out there into the larger universe, I won't get to see most of it – unless I live to be 100+. (Not likely!) But then I had a thought: I'm at least in good company. So many of my heroes are gone now, & many of them were sci-fi writers, astronauts, scientists… none of them will get to see even as much as I will. The big 3 of sci-fi got to see us go to the Moon, & the start of the space shuttle program. That's it. Now, with (seemingly) the whole world racing into space, it's a sure bet *somebody will get there – and stay there. I guess I'm luckier than I thought. I vow to enjoy what I can, & to keep in mind that – politicians aside – this is all of humanity's victory – no matter who gets there first. Amen. tavi.

  58. @Fraser Cain

    I had some ideas about making solar sails…. a few thousand times larger. It'll take some scientific advancement from where we are today. Mostly in cheap aerospace-grade mass production methods of large sheets.

    You can start by making the sail thinner. By using a material like graphene, or <1micron reinforced Kapton (2.5x as much stretch as Mylar, exceptional dielectric), or some other material that can be sewed together into a massive oragami like pattern when folded up (without cold welding or static cling!)… make an assembly-line mirroring process that uses thinner than a 100nm layer…. Then you can make the deployment of the sheet much faster, like using small offset-thrust ion or gas thrusters to pull out each of the 4 corners of the sail thousands of times farther than with extendable support arms…. You can use the build up of electric charge via photons hitting the mirror or the 'sewn' in support structure to provide a stiffening force that helps straighten and extend the solar sail… You can also find a way to compress it slightly while folding it so that it has a natural spring pressure to help it unfold.

    Might be able to make it to where its as big as texas after half an orbit (hopeful guesstimate), and it would need to be launched into an eccentric or hyperbolic/ transfer orbit so one corner doesn't dip into the atmosphere. As it is being flattened out into its final size, the center will have received more push from the sun so it will start to look like a supremely massive white-silverish umbrella. Figure out how to keep it perpindicular to the solar flux, since the starting umbrella shape might make it tumble (should flatten out over time, and if in a bodily shadow shrivel up a little). The denser atmosphere will cause it to rotate clockwise if in a retrograde orbit, counterclockwise if in a prograde orbit to the earth's spin, along the normal-antinormal axis, unless at a strange deployment rotation. ..Assuming the overall stiffness is high enough, and the other forces low enough to not screw it up like a piece of seran wrap in the wind.

    I don't really like the idea of unfolding methods that require rotation, probably because of the sheer amount of velocity it would have to pick up on such a large scale (and the size of the counterweights), though you could enginner it to where the center structure slows down and turns the rotational velocity into sail/shield expansion pressure, assuming it comes to a stop close to the end of the final deployment size, maybe 20% margin. Still, idk about if the film would be able to tolerate that without rippling and doing weird stuff like spin becoming off-axis as it processes through the orbit.

    Not sure why you would want it to deploy to such a large size (eg texas) so early except to try and act as a solar shield in an emergency situation, or to make use of the free solar acceleration to boost the trajectory of the massive sail before the sail floats into the shadow of the earth. Maybe its more economical that way and its already heavy enough, who knows.

    If you have any better ideas, please I'd love to hear them…
    #scienceisawesome #lightsail2

  59. I've heard about cameras that are the size of a grain of sand which can take pictures at 250×250 pixels. Would this be a viable camera for breakthrough starshot?

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