What impact will Discovery's mission have on the US space programme?
The crew on board the space shuttle have conducted inspections of Discovery's belly and repairs to the shuttle have also been carried out.
Stephen Robinson has begun a unique spacewalk, going under the orbiter's belly to remove two ceramic strips sticking out between heatshield tiles. Nasa engineers are concerned the strips would cause part of Discovery to overheat as it re-enters the Earth's atmosphere.
Discovery had been due to return to Earth on 7 August, but Nasa has decided to extend the mission by an extra day.
What do you think of the mission so far? How do you feel about the mission being extended? What do you think about the repairs? Send us your comments.
This debate is now closed. Read a selection of your comments below.
The following comments reflect the balance of opinion we have received so far:
The money that is spent by the American government on space exploration could be much better spent on healthcare and education. This would be much more beneficial to the American people than Discovery's mission.
Carolynne Burkholder, Vancouver, British Columbia
I cannot believe that the crew had to cobble together a hacksaw. A small box of tools from any DIY shop would have done the job. Also removing a gap filler between the tiles exposes a gap. Surely the wind can get in and potentially lift a tile causing a fatal problem.
Norman West, Truro, Cornwall
Whilst I can see that advances may be made through this work, I saw two items on the news last night - one about children dying because they haven't got a few quid, the other about spending millions on keeping the shuttles going in and out of space. Priority check please.
Mark, Didcot, England
Space travel is dangerous, pioneers are going to die, but it is worthwhile. What is needed now are new spaceships to let us travel between planets. At the moment all our eggs are in one basket, we need to find other homes on other worlds. We have made this one nearly uninhabitable. I would go into space whatever the risk.
Maybe if all the countries stopped being so petty and pooled their resources, we'd have superior technology and fewer incidents like this. We don't need to race against each other anymore to try and prove who's superior; instead we should look to a future of co-operation.
Gaz, Cardiff, UK
I will never understand why we waste so much money on primitive space stations and shuttles which clearly have no function for the human race at this time. I don't know why we don't get all our experts and fund them in coming up with unmanned technologies and technology in shuttles that could take us to planets not to a tin can in the sky which is over expensive and serves no function to the mass population.
John Gearing, St. Helens, UK
Fascinating a Brit would ask the question why the US is sending people into space. As the Brit, George Mallory said in 1924, "because its there". Mt Everest killed Mallory and we remember him for his quest. In a similar quest, the US will continue to go into space - because its there.
John B, Windermere, Florida
Do some of these contributors have no soul? What could be more magnificent than seeing human beings taking risks to explore the unknown; triumphing over the problems they meet along the way; opening up new horizons for the rest of us? Yes let's invest in a new space transportation system, and more manned flights, and unmanned probes and a bigger, better space station. But to claim that stopping the current flights is sensible shows no faith in the species at all. Stop looking down at the ground and start looking up at the stars.
John R Smith, UK
Please, armchair scientists, let the experts at NASA do their job making the risk calculations. They've got the know-how and the tools to make the decisions. Not you or me.
This is the most ridiculous expenditure of precious funds in a time of great national travail. NASA is an anachronism, a patronistic pet rock that has no justification whatsoever, especially in the current environment in which civilized societies are fighting for their mere existence. The irresponsibility in launching this mission in the face of known deficiencies is appalling.
C. A. La Varre, Newport, RI USA
Why-oh-why does the media take such a negative view to what the men and women on sts114 are doing. The media paints such a doom and gloom picture of what is happening above us. We as a united world should watch and praise these people who are up there performing the most fantastic things known to mankind. Yes there is a difficult time coming on returning to earth but the crew at this time seem very positive about it. May I suggest that you all watch Nasa tv on the web for real live happenings.
Phil, Hampshire, UK
NASA is undergoing drastic changes. I think the US should pause and take stock of what's happening to their Space missions. Give it a break, sort out problems and return 10years later. I wonder how the US ever landed man on the moon? Did they really? I wonder!
Errol, Dubai, UAE
Space flight is still in its infancy. So the fact that an astronaut was able to make a repair to the shuttle in space is a great triumph. NASA should look on this feat in a positive light, not a negative one. We know in the days of sailing ships as they travelled the globe to discover new lands, there were many times when sailors had to climb up masts in storms to make repairs, so is repairing space craft in flight any different?
Leon Aarons, Petach Israel
Another piece of space theatre, justifying manned flight. Unmanned craft can put payloads into orbit much more cheaply, as well as exploring other planets.
Martin, Dubai, UAE
I've just seen a picture of the tool, held together with strong tape that the astronauts used. It's great to imagine that a billion-dollar aircraft can be saved by a bit of strong tape and some elbow grease! It's that sort of thinking that's saved astronauts in the past. Good luck to them, hope humans carry on going into space for many more years.
Dave, Manchester, UK
This spacewalk and repair demonstrates two things. Firstly, the courage and initiative of the astronauts, secondly, the importance of retiring the ageing shuttle fleet and building a modern spacecraft. Electronics and materials technology have advanced tremendously in the past 30 years, but the shuttle is still using outdated technology.
Gordon McStraun, UK
So, the offending piece if gap filler from between a couple of heat shields. I'm no NASA expert, but doesn't this mean that the is now a gap between these tiles?
Michael, Bucks, UK
I think it is fantastic that Discovery has launched and its mission is going well. A lesson has been learnt from Colombia, and indeed, Challenger. The astronauts are all volunteers, they know the risks involved, and that is why I praise and thank them. They are incredible people.
Kirsty, Cambridge, UK
So what if the filler problem has to be fixed with a jerry-rigged hacksaw? This type of ingenuity has been saving lives since the age of tall ships and can only reflect well on the tenacity of the Nasa engineers and astronauts. Remember when the Progress hit Mir? Apollo 13? We need the experience of these problems to give us the know-how to survive in space and give us the confidence in our ability to solve problems on longer, bolder voyages.
Tim Parker, Edinburgh, Scotland
I work with Remote Operated Vehicles in the Oil and Gas Industry. I am amazed that the crew of the Discovery need to cobble together a makeshift hacksaw to carry out a job on the tiles. The shuttles are old and things will go wrong so you would expect a decent tool kit to be onboard.
James, Paderne, Portugal
Why are the Americans still sending people into space? If they want to explore they should be thinking of unmanned flights with intelligent technology which can spend decades in space. This should help the ozone layer repair itself. More is needed to be done to explore and catalogue this planet and its systems, this will be of more benefit to mankind and our home than space travel.
Haz, Nottingham, UK
Is going up in the Shuttle much more dangerous than sailing unknown oceans a few hundred years ago in wooden ships? Thank goodness that throughout history not everyone has wanted to sit at home in comfort in their own small world.
Simon, Manchester, UK
With so many comings and goings to and from ISS, would it not be sensible for just the bare minimum of crew to return in this shuttle and send up a half-empty shuttle to collect the rest of them? Why take unnecessary risks?
Fraser Irving, Sheffield, UK
Until now, the shuttle missions have been routine, like taking a walk in the park. But the reality of danger with the loss of two shuttles has almost brought the space program to its knees. Should it continue? Of course it must go on because too much is at stake. Closing the space station, and not looking into space is the worst we can do. Life on Earth is becoming dangerous. We must look to the stars if humanity is to survive.
Walter, Chapel Hill, NC
I think - and hope - this flight is one of the safest ever. My guess is the problems have appeared simply because they have been looking for them far more carefully than before. However, there's no doubt a replacement spacecraft is needed. The private "Space Ship One" has a slow re-entry, avoiding thermal problems. Is this possible from orbit? And a separate, unmanned cargo vehicle seems a "no-brainer".
Pioneers always take risks so that everyone else can eventually follow. It must be frightening for the astronauts but the space programme must prevail. Updated technology is definitely needed. Unmanned missions are a good idea, but ultimately there is no substitute for human actions and reactions.
Interesting to note that the two shuttle losses have not been due to design or engineering flaws in the shuttle themselves, but rather the propulsion system. For 30 year old vehicles, I think the shuttles are doing pretty well, and I am sure they will continue for a long time.
Space exploration is dangerous and the crew knows this better than any of us - and they still volunteered for it. My view is that we need to continue to explore space and the shuttle repair should be seen as an experience that needs to be faced at some time. Let's not be weak about this.
What NASA has done is simply awesome. NASA is the adventurer of our era, looking at and investigating things that are far bigger than us. I say ground the space shuttles, but do not skimp on quickly building bigger, better, and safer spacecraft to replace them.
SK, Ithaca, NY
The few people who mock space projects should not use anything connected with space technology as a protest! I bet hardly anyone would manage it or really want to. Space technology is too integrated in our daily lives now; we all enjoy the advantages we get from it. Nasa TV via the net alone shows me how wonderful space is.
Peter Byrd, Worcester
I have just returned from Florida where I was privileged enough to witness the breathtaking launch first hand. It seems as though there are increasing difficulties using these shuttles. Are the lives of 7 astronauts each time it takes off a risk that is worth taking?
Given the loss of Columbia and the uncertainty of this mission, NASA should scrap the shuttle programme. Luck prevented previous disasters and it would appear NASA's luck has run out. What makes them feel confident that they can repair in space what they failed to repair in two years on the ground? My thoughts are with the families of those on the ISS.
Phil, Bracknell, UK
The problems with Discovery must have been encountered with all the previous shuttle flights. It appears that each time it took off, it was Russian roulette as to whether it would return safely. This program should be abandoned until a new and safer means of transporting the shuttle into space can be developed.
Even if the pieces sticking out are pulled or hacked, will the resulting depression between the tiles create a possibility of a chink in the armour? Even a depression can alter the aerodynamic behaviour (as in golf balls). This will create uneven heat distribution.
K Chowksey, Bangalore, India
From the idealists point of view we really should not be thinking about costs here. Space exploration is vital, not only to our technological development as a species, but also in terms of our wider understanding of the universe. The whole NASA infrastructure is quite frankly awesome. Every endeavour has its risks and we've seen the tragic consequences of those risks with the previous accidents.
We need to explore space; when you go to hospital and have a CAT scan or an MRI, that technology has come from the space program. There is nothing wrong with the shuttle - the problem is with the way it is maintained. They need to do better, I don't know why don't they paint it again, and seal the foam.
Carol, PA, USA
The saddest thing for me about this mission is that the next time the ISS is visible from England on August 11th, the shuttle will have already left. Hopefully we'll get to see the shuttle during the next mission. After the moon, the ISS is the brightest object in the night sky.
John Airey, Peterborough
Major advances need to be made to the whole concept of effective re-entry heat-shield technology. Even before lift-off, I looked at the images of the underside of the shuttle and thought that it looked like really bad bathroom tiling. Initially, I expected it to be a smooth, seamless surface, but it was a patchwork of light and dark areas with patches that looked more raised than others. I assume that tiles are the best option at the moment, but in future this issue needs to be solved completely.
If NASA has decided to just rip out the relatively small strips protruding from between the heat shield tiles, then why can't they ask astronaut Steve Robinson to take his experimental repair kit out with him and fill the gaps with the mastic gum that they used to 'fix' the tiles in their earlier experiments?
Paul Greer, Gothenburg, Sweden
I worked as an engineer on Skylab in the 70s and I consider this NASA debacle a disgrace. Unknown risk is one thing, but gambling with lives on known problems with solutions is unacceptable. I say: bring some crew home in Russian capsule, leave the rest of the crew up there, fix the foam on Atlantis (and everything else possible) and then send a rescue mission. Then ground the antiques and use modern technology to build new spacecraft.
Rich Dusek, Orchard Lake, MI, US
Bruce from Huntsville says it's not a trivial engineering problem and he's probably right. But that doesn't alter the documented fact that NASA has sent people into space against the advice of contractors who have told them that certain aspects aren't safe. If shuttles are prone to bits falling off then they shouldn't be flying.
David, Chelmsford UK
Why do people expect space travel to be perfectly safe? Look at any picture of launch and remember the orange tank is full of fuel and both white rockets once started can't be stopped. Man in space is an essential part of our future. The Earth cannot sustain us forever particularly its natural resources. I also think people should recognise that Nasa don't build all the parts and therefore an outside company may be partly responsible.
The problems with the Space Transportation System are a classic example of what happens when whole-life costs are not taken into account during early design phases of the system. Congress chose to buy Shuttle on the cheap, opting for solid fuel boosters and a disposable fuel tank instead of spending extra money upfront to design a fully-reusable fly-back first stage to take the Orbiter into space. The result has been far higher operating costs and, tragically, the loss of fourteen astronauts. Will it be too much to hope that senior agency managers and politicians will learn these lessons in defining our future access to space? In Europe as well as the USA.
Phil, Bath, UK
So far this particular mission has been very worrying for relatives of the Discovery crew. Any venture into space is a risk, but this one seems to have gone ahead knowing this risk factor was much higher than usual. Why are these missions so important? The risk factor is too great to risk innocent lives. Stop them now.
Jose A Holmes, Loughborough, England
I wish the crew a safe return but am sorry to see resources wasted on a manned flight with little real value for essentially political and PR reasons while much more scientifically valuable unmanned work is scaled back to pay for it. This is all about the advancement of the USA, not science.
Julian, London, UK
The debris issue has been present in the shuttle programme from day one. The tiles themselves are so fragile you can break them with one hand. The space shuttle is a wonderful vehicle, but sadly owing to it's bizarre design, is inherently dangerous and needs to be replaced soon. As Richard Feynman said after the Challenger disaster, "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled."
Chris Dyer, Bristol, England
I, like most people connected with astrophysics, think that the immediate future of the space program will be best served by robot missions for at least the next twenty years. It's not taking a step backwards; it's about developing and testing new technologies which will eventually be applied to human spaceflight. For the same amount of money you get much more science done with robotic missions because you don't have to worry about the fragile humans.
Dr Malcolm Fairbairn, UK/Sweden
As an aerospace engineer, in this particular instance I am not worried about Discovery. All indications are that the debris did no damage. Long term, though, it could be a problem. The space shuttle has never fulfilled the promises that were made for it. It is an expensive vehicle of very limited utility. It consumes resources which could be better used elsewhere in the US space program.
Andrew Ogilvie, Modesto, California, USA
Robert Heinlein said it: "The Earth is too small and fragile a basket for humanity to keep all its eggs in." The only safe place to be when disaster comes (an asteroid for example) is somewhere else. Well done, Discovery. Keep it up.
John Fielder, Workington, UK
There are a lot of negative comments on here by people who really have not done their research. There are so many inventions that have come to be due to space travel most are indirect, technology passed to the public after it has been created to aid NASA and the like in various projects.
Adam Ransom, Birmingham
Space flight is one of the things that most excites me. It breaks my heart that foam broke off the insulation again. Apparently, the design has a basic flaw; the vulnerable heat shield is exposed to a bombardment of debris falling of during take off. In the more old fashioned designs, the heat shields were protected during take off.
Jehuda Arieh Veenman, Haifa, Israel
It seems to me that the logical fix for the launch system would be to mount the shuttle higher relative to the fuel tank. The coldness of the fuel is always going to be a problem in causing freezing of water and air in and around the foam insulation. Since that is the nature of the beast, get the shuttle out of harms way above the possible falling debris
Nigel Dandridge-Perry, Los Angeles CA, USA
Good luck Discovery, I look forward to seeing a safe flight back to Earth.
There is no progress with manned missions. It's more of the same. While unmanned missions are discovering lakes of water on Mars, landing on distant moons and exploring planets, the manned missions are trying to work out how to stop foam falling off the fuel tank. Leave floating around in orbit to the Chinese and get exploring.
Matt, Amsterdam, The Netherlands (ex. UK)
Those who fly orbiters know the risks and accept the challenge. The shuttle programme shows the greatness the human race can achieve when we focus. A commitment should be made to give it whatever financial support it needs to continue. NASA TV shows Discovery's latest mission is gripping. We owe it to those astronauts who have lost their lives in space exploration, to carry on the work that they couldn't finish.
D Ward, Portsmouth
I have become addicted to NASA TV over the last few days, and find myself staring into space, thinking of Discovery up there somewhere...looking back on our little planet from a distance. I am surely concerned about the debris; remember NASA did not think this would be a problem for the ill-fated Columbia crew either. They have spent two years and thousands of dollars on this problem - so yes, I think we should be concerned, not only about the debris' implications, but also that NASA got it wrong again.
Verity Worthington, Bewdley, Worcestershire
Hundreds of years ago people were afraid that they could sail off the edges of the earth. Thank heavens there were brave sailors then willing to push the limits of courage and technology, and thank heavens we still have them today. I'm also grateful that there are still those willing to fund such expeditions.
Rob G., Kansas City, USA
The disaster 2 years ago, and these recent problems with the shuttle show that NASA really need to get on with developing the next generation of re-useable shuttles. Technology has moved on so much in the nearly 30 years since it was developed with computer technology and new lightweight materials. If they don't, then the private space firms will take over, while NASA keeps flogging a dead horse.
Tane Piper, Edinburgh, UK
We are all with you, looking forward for success. God be with you. No surrender no retreat.
Martin Madulu, Moshi - Tanzania
I am more worried about the apparent loss of a tile than the foam. If any of the tiles were damaged, the mission is in jeopardy. After the Columbia disaster, I read an article published in 1980 calling the shuttles 'death traps'. Considering that we've already lost half the fleet, I think it is high time NASA invested in a different, more robust technology.
Istvan, Detroit, USA
My family and I were vacationing in Florida at the time of the launch. We saw it speeding skyward from the car on our way back home. I am an aerospace design engineer specializing in Flight Dynamics. My concern really lies with the inadequacy with which NASA has dealt with the foam/tile problem. The safety of the crew should be of utmost importance, not launch schedules.
Only those at NASA who have looked at the images of debris falling will have the best idea. The crew's safe return is just our concern but it's their mission.
Venkat Maruthamuthu, Urbana, IL, USA
Why was this problem not resolved after Columbia two years ago? It is very wrong to send yet more people up there without being absolutely sure that it's safe. Perhaps space travel should wait until we have progressed far enough that we are not relying on tiles that can just fall off?
Catherine, Cheshunt, Herts
Great to see the shuttle soar again. Our future lies not on Earth but out there somewhere. No matter how you argue it, in the future this planet will die and so will all those life forms still on it. If the human species is to survive, then it must do so elsewhere and this sort of technology is the first step towards that ultimate goal.
Ian Jordan, Wokingham
This is not a trivial engineering problem as some have implied. There are two types of foam: a lightweight foam covering the large areas of the tank and a dense ablator foam covering areas exposed to aerodynamic heating. The foam is exposed to supersonic airflow at about 27000 km/h (17000 mph) during launch. There are shock cones coming from the orbiter, the connecting struts and solid boosters which impinge on the tank. There is also a lot of vibration. The foam formulation was changed in 1996 to comply with the Montreal Protocol and eliminate the Freon propellant. Most of the foam issues started after this change and may or may not be associated with it. The shuttle is due to be retired in 2010 and solving this problem is important for future spacecraft design.
Bruce G, Huntsville, USA
Why can't the return module be encased within the main take off rocket? This would prevent bits flying off from damaging it.
Tony Lee, Telford
We were on vacation in Orlando, and had tickets for the Astronaut Hall of Fame to watch the original scheduled lift-off on 13 July. We had such a good view, but with about an hour or so to go, the launch was cancelled. We were gutted to have missed such a spectacular sight! We watched it on television back here in Ireland, but felt we had a special bond with STS 114 - Return to Flight. We just hope now for the safe return of the shuttle and its crew on 7 August. Good luck to them.
Hutch Family, Ireland
One day when someone is sipping cocktails on Saturn's lunar resort, whilst looking back at the Earth and the distant Sun, they'll thank these brave people for risking their lives. Let's keep our nerve, and not look back.
Chris Phillips, Chelmsford, Essex
I used to work at one of the Nasa Centres (in Maryland) and I hope that space exploration continues. As a scientist it is an inherent part of our nature to explore, discover and find out about the unknown. I was overjoyed to see the launch of Discovery and hope, beyond all hope, that they make it safely home. As Nasa have said - "exploring space is not for the faint hearted' - it's a huge undertaking". The astronauts know that, we all know that. These are very brave people and I wish them, and Nasa, well with their endeavours.
Caroline, Edinburgh, UK
Watching this made me feel giddy. Now hopefully we can complete the ISS and get on with the business of colonising space. The spirit of adventure lives on with Discovery and her crew.
David Mills, Ballymena, UK
We were very privileged to be able to see Discovery launch when it flew mission 105 and the impression it left us with was 'it was amazing to see'. We believe that the crew and the engineers will be able to work together and face the challenge of bringing back this magnificent ship. Instead of shrinking from the challenge we should rise up to it just as they did in 1970 for Apollo 13, it is only by stretching our knowledge such as in times of emergencies that we reach beyond our capabilities. Good luck and best wishes to the crew and engineers.
Julie and Robert, Manchester, England
Congratulations to NASA on another successful launch. However, I would like to see the shuttle retired and replaced with a newer and more capable fleet of vehicles. Not only will it be safer and hugely beneficial to space exploration, the project would provide thousands of jobs, contracts to companies and benefit the global economy.
People seem to forget that manned space travel is still very dangerous and those brave astronauts know the risks. Foam has been falling off fuel tanks for nearly 25 years now. Perhaps money should now be invested in developing better glue and a more efficient reusable manned space travel system.
John Ellis, Nottingham
Statistically, if commercial flights carried the same risks as spaceflight, there would be about 500 airliner crashes per day. One therefore has to applaud the courage and determination of those people who accept this degree of risk in pursuit of our quest for knowledge. We are an inquisitive species, in this case pushing the boundaries of what is possible. I wish those seven brave souls a safe return.
I've been following the 'space race' since Sputnik and the Mercury missions, and I can't think of anything more exciting than a successful launch. But why don't we stop racing against each other and form stronger international collaborations to make space travel safer?
J Forman, Los Angeles, USA
It amazes me how many observers believe they are more of an expert on shuttle safety and capability than the engineers at NASA. The fact is, the men and women who work at NASA are at the top of their field. If they say the shuttle is safe to fly, it's safe to fly.
James, Los Angeles, USA
It was a beautiful launch. The Space Shuttle program has been remarkably successful despite the previous disaster. Nobody can engineer absolute perfection, but this was very close.
H Neil, South Texas, USA
I am very concerned about the damaged tiles on Discovery, especially in light of NASA's apparent slowness in acknowledging that the take-off incident with Columbia caused the disaster upon return. There is an option for the crew of Discovery - to wait on the space station for rescue. How can we even contemplate risking their lives? If the problem is serious enough to ground the fleet, Discovery too should be 'grounded' immediately.
Sharon, Dallas, Texas
I once saw a presentation on how the Challenger disaster came to happen and how it could have been prevented and it made my blood run cold. Suffice it to say, I have nothing but the most profound admiration for the courage of the crews of the shuttle. I'm not a religious man, but I just hope to God they all get back safely.
Tragic as the Columbia accident was, the astronauts died doing what they loved - exploring space, a privilege only the select few get to do. They also died at the end of their trip so they got to enjoy being in space, unlike the Challenger crew. Before the Columbia accident, I would expect that the shuttles got through intact in much worse condition than Discovery. I am not that concerned, although I will follow the investigations with great interest.
The shuttle has been up and down into space about 50 times before the Columbia incident. I cannot believe that bits of foam from the fuel tank didn't come off during these trips. Aren't Nasa being a bit super cautious about this problem? Can't they encase the fuel tank in some sort of wire mesh in order to prevent the foam from breaking off? In such a high tech programme, it seems ridiculous that it is being jeopardised by something so simple.
What exactly are they doing out there that they have not had the chance to do before? First of all get a new ship and then go somewhere else than the moon! That impressed my grand father, it will take more to impress me!
Mathieu, Gatineau, Canada
Bits of foam have probably been falling off the shuttle since the first launch, but it's only since a piece of that debris caused the destruction of Columbia two years ago that anyone has noticed! Only now we have cameras watching every single part of the craft do we see what may well have been happening all along. Carry on as normal.
Simon, Peterborough, UK
I remember watching the first ever shuttle flight as a kid. I watched the launch the other day and got the exact same feelings of awe and excitement. The shuttle launch is a wake up call to everyone. Sure the world has problems right now but despite those problems, look what we're capable of! My message to Nasa, the ESA and all the other agencies? Keep going people. Take us there!
Andrew K Jones, Wrexham, UK
I watched the launch live on the internet and was overwhelmed. We won't know of the mission's success until 7 Aug, but what surprises me is the US way of making everything BIG and the huge overhead costs. It's all show and little substance. After having spent $1 billion and 2.5 years on the debris falling cause, they are back to square one and the shuttles are grounded again! On the other hand the Russians are making safe manned space missions with pinpoint accuracy every 3-6 months at a fraction of the cost.
Rakesh, London UK
I read once that spending on cosmetics in the USA dwarfs the NASA budget. Let's get things in perspective. Without space exploration we would not have computers, hi-technology materials etc, all of which were a by-product. If more is learned about our planet and its self-destructive population on each mission then we should keep it going. Come home safe guys!
Jim Kirk, Basildon
Does anyone know why debris falls off a multi-million dollar spacecraft? Can't some sort of outer layer be put around the fuel tank insulation to stop it disintegrating? I'm not an engineer - I need someone else to explain it!
Rather than risking the crew and the shuttle, if it is damaged, why don't they leave it up there as service vehicle and bring the crew back in another shuttle at a later date? If NASA wants to survive they need to start making people believe in them again. Good luck Discovery!
The space shuttle was under funded during its design and construction and the compromises mean it will never achieve its true potential. The sooner it can be replaced with something newer and simpler the better.
David Patrick, Reading
Trying to make space exploration 100% safe is just nonsense.
My heart sank when I heard the news that tiles had once again fallen off the space shuttle. If the cause of the tiles falling off is simply the vibration and air flow, then I wonder what will be the effect of the searing heat of re-entry.
Roger Campbell, England
Having watched the space shuttle launch on TV, it is good to see such a majestic craft finally back to what she was meant to do. Well done NASA for getting the space shuttle flying.
No-one made that big a deal when tiles were missing from the OMS pods after Columbia's maiden flight in 1981. When designing this vehicle they must have made a risk assessment to determine safety parameters, and unfortunately the loss of Columbia has made them refine these parameters further.
Tim Parker, Edinburgh
We watched the launch from our beach, about 90 miles away. It was spectacular. There are many more cameras watching the exterior shuttle craft than ever before which have alerted to the problems. The engineers working for Nasa are tireless and will get the current crew back safely one way or another. The space programme will continue. The only unknown is manned flights. The Mars rovers are still sending pictures and information long past when they were suppose to. Nasa will continue on and I believe has more government funding this year, or is due for an increase. Private companies are currently working on safe space travel for human passengers in the US and abroad I believe.
Joan York, Daytona Beach, Florida USA
I have witnessed the launching of space shuttle Discovery on television screen. Nasa's team on the ground and the astronauts in the space are doing a great job for the mankind, as their experiences in the space will benefit the entire world. I pray for the safe return of the astronauts and happy landing of the space shuttle. As a human being, I am equally concerned about the debris which has fallen at the time of its blast, but hope that the space shuttle will not face the same problem as it did in the past. The safe return of Discovery will boost the moral of Nasa's team, who had worked day and night to make the space shuttle's mission possible.
Syed Mateen, Karachi, Pakistan
Any country with ambitions to have manned missions to space would be more than happy to have a craft as good as the space shuttle. If there is a cheaper way to break away from earth than I am all for it but I am not sure how much safer it will be. Exploration has always been a dangerous business.
Erik, Ft. Collins, U.S.A.
Manned space flight is a dangerous and expensive anachronism. Look at the success of Hubble, the Mars rovers and the Cassini/Huygens mission. You can do 10 times as much real science for half the cost and no risk to life by concentrating on unmanned space exploration. And tell me, weren't the pictures of Titan far more exciting than anything the crew of the shuttle are likely to get up to?
Max, Abu Dhabi, UAE
I read some of the comments here with disbelief. Yes, we all know that there are problems in some areas of the world, it doesn't however mean that everything has to stop because of that. I can think of a lot more things which are more of a waste than space exploration. I'll bet half the people complaining about NASA being wasteful drive gas guzzlers and don't bother to recycle. The shuttle mission is vital to all areas of science and I'm glad it is flying again. The space shuttle is not an old machine; Discovery has only flown 30 times before. Most commercial airlines fly that often in a week!
Dave, Slough, UK
Many congratulations to NASA. As a teacher I teach children who are fascinated by space. It is good that the space missions continue. It allows children to hope and dream that they might reach the stars themselves, one day!
We all know that it costs millions of dollars to support the Space program. One could argue that money could be better spent elsewhere. The fact is we as human beings need to understand in order to learn new technologies and Space exploration is just one of many things that need to be understood and conquered. There will always be many arguments for and against the Space program. All I can say right now is well done to NASA and my best wishes for a truly successful return to space flight for Discovery.
Andrew Howlett, Cape Town, South Africa
Good luck and a safe landings to the crew of the Discovery. There are some here that would have the USA quit funding the space program until all the worlds' problems are solved. Will you tell your children to wait for that day before pursuing their dreams?
Michael Rosenbaum, San Francisco, USA
A plane crash or 9/11 does not stop air travel, so why should the Columbia 2003 disaster stop space exploration? I'm sure Discovery will make it back safe and the astronauts will be given a well-deserved pat on the back.
The Shuttle might be old but it still works, and has done the world a huge service towards on earth and in space exploration. Those who complain are clearly members of the flat earth society, and yet I bet they use technology every day? Someone has to push the envelope. GO NASA GO!
Phil W, UK
Good launch. Let's just hope she comes back in one piece.
The shuttles are aged dinosaurs that need to be "moth balled" before more lives are lost due to fragmenting Styrofoam. Perhaps we should all consider shifting funding away from NASA and put it towards alternative fuel sources. It would be revenue better spent.
Kurt Stuchell, Cambridge, USA
Scuttle the shuttle! Obsolete equipment supplying a pointless lab. Much fanfare about increasing aid to Africa by $25B but US military budget $400B makes you ill!
Gordon, Auckland NZ
I cannot stand the mentality of myopic people who would rather we abandon the natural impulse to explore our surroundings, and instead focus on futile efforts to tackle every mundane earthbound problem. Surely, the sight of the shuttle blasting off into orbit is the most poignant statement of mankind's destiny.
Kevin, Charlotte, North Carolina, USA
With so much bad news in the media: terrorism, war, poverty... it's wonderful to see what we as human beings can achieve, when we put our minds to something positive. We have the potential to achieve great things. The crew of this shuttle mission are from different countries, cultures and backgrounds; proof that if we work together, we can produce something that makes us all proud.
Charlie, Newcastle, UK
To all those who claim the space programme has helped advance medicine and technology..... think how much further along in those fields we could be if all the money wasted at NASA went into development.... let alone feeding the poor. Shameful waste of resources. I don't want my tax dollar to be spent this way.
P. O'Donnell, Rotorua,N.Z.
There are always small-minded people who are terrified of exploration. If we had their way, we'd still be living in trees afraid of the dangerous savannah! Thankfully we've always had a few who have done their best to pioneer new territories and worlds.
Digby Knight, Henley-on-Thames, UK
I would argue that Nasa is somewhat of an anachronism. The "glory days" of the space race with Russia are over. Instead, space exploration should be run by the National Science Foundation. There, private and public money can be better organized to fund missions. The NSF already runs most of the science stations here on earth. Why should space be any different?
Greg, Alexandria, VA
Space exploration *is* a waste of money. Had the billions been invested directly in more down-to-earth technologies, we would have seen the same spin-offs in medicine, IT, and transport.
I can't believe the childish reactions to space exploration from folks like Mike and Anon, UK. Grow up, guys. Space exploration represents humanity at its most amazing. You're obviously just bitter because the US is leading the way. Typical.
Shawn, Washington, DC, USA
Exploration, of all kinds, has always helped man push the boundaries of technology. The space programme is no different. For this reason alone it is invaluable.
Jason, Detroit, USA
Looking at the shuttle I am always reminded of those creaking old 50's and 60's airliners you still see rattling around developing countries. Good in their day, but now so ropey and tired that they just scream "death trap". It says it all about the shuttle that despite all the delays and expert checks, something still fell off it on take off. It's high time this heap was scrapped, and a replacement worthy of the 21st century was introduced in its place.
Dan, Yateley, UK
So the new UFOs are Unidentified Falling Objects?
Phil Jones, Frangy, France
If you watch the film of the launch the piece of debris that falls off after the booster rocket drops off does not come from the shuttle it comes from the giant fuel tank, which is 'disposable' anyway.
John Nichols, Brackley, Nnorthants, UK
How would Brits feel if Americans were talking about how Britain should spend its money?
Michelle, Raleigh, NC
I think that NASA is still too hurried in launching the shuttle when the debris problem still exists. Maybe they should solve out the problem wholly before doing any thing else. But the fact still shows that NASA has succeeded in launching the shuttle into space. Maybe that's an incredible luck, although we still don't know about the return of it. But I believe it will succeed, too. God's will give luck to the crew.
Nguyen Hoang Giang, Hanoi , Vietnam
It was an excellent feeling seeing discovery go like that yesterday. I am really happy for NASA and I just pray she makes it back down ok, that will be the icing on the cake.
Seun, London UK
Oh dear! The USA are off again trying to show how they can spend billions on space exploration, meanwhile trying to flex its muscles all around the world causing chaos- unbelievable!
Mankind is not content with polluting the earth! It now wants to pollute space as well! How sad! Millions starve while the USA burns dollars - what for? It truly is a sick world we live in these days!
To Anon, UK - the fuel is clean and non polluting - just water produced. And as for waste of money - tell me about the Dome and the London Olympics. Longer term, I know what is more valuable!
I'm so glad to see the space programme resume shuttle launches. Space research is costly, but it's like buying a lottery ticket - you never know what you're going to get back from it, but once you go out there, there's a chance you might win big. And we already have - people have cited the benefits that have come from the space programme. Here's to more exploration outside our atmosphere!
Tony, London, UK
I felt privileged to have been in Florida for the launch. It went off on time and from what I gather from reports, was perfect. It's something to tell the grandkids one day.
Space travel fires the imagination! To all those that criticise that the shuttle is old and the fact that its had two failures should perhaps think again the next time they board a 747 on route to their holiday destination.
Tim Goodchild, Surrey
Absolutely fantastic pictures from discovery, especially when the external fuel tank was detached from the shuttle with the curvature of the Earth in the background. Overall great launch, well done NASA.
Paul, Coventry, UK
The American space programme is a great achievement and it is important that it continues. The human race is capable of great things and it is not in our nature to keep still.
Terry, Crewe, Cheshire
My gosh! The people saying the space program is a waste of money?! The commercial products used now as a result of NASA are staggering. CAT scans, dialysis machines, materials in your athletic shoes, water purification technology, cordless power tools, cool suits for firefighters, physical therapy equipment. The list goes on. The program is invaluable!
Most of the people on here with negative comments do not realise how much space has done for humanity. Many medical experiments have been conducted in space which was the only place that it could be done. The results of these experiments have saved thousands if not millions of lives. I think its well worth the effort and money to sustain humans in space.
Carl Lennon, Northampton, UK
Although America has proven itself to be the world's best engineers, NASA is living on past glory. Many of its best scientists and engineers have left, it is no longer in the public limelight unless it has a disaster, and it is grossly underfunded. America should reinvigorate the program with major new investment and ambitious new goals or shut it down. As the EU space agency has recently learned, you can't explore space on the cheap. This old technology and this antiquated worn out hardware needs to be retired along with the mediocre management which has taken over.
What a novel way to distract your nation from the real problems at home and abroad. The cost doesn't matter since the nation is paying the bill.
There are those who say space exploration is a waste of money. On the contrary, space travel forces society to stretch and reach further in order to solve highly complex problems associated with putting man into space. The solutions to these problems are broad and serve mankind in many ways. The space program enables us to move forward faster than we otherwise would. Without such large goals our advancement slows and we become lazy.
David, Philadelphia, USA
Come on people, of course sending people into space is dangerous and expensive. That doesn't mean we shouldn't do it though. Even if space exploration did not lead to technical advances and practical application, it would still be worth it. Why? Because it's cool. We put a man on the moon, that's pretty impressive considering just prior to WWI a man could only travel as far as a horse could take him.
Stu, St Paul, USA
The view from the fuel tank at over 14000mph was fantastic! Why aren't other space agencies doing this for the public? Engage us!
Rod Aries, Glasgow
Every time I see a rocket launch I think that Newton made it possible; his equations are still used to calculate the orbit. How many other things in use today were invented over 300 years ago?
A sense of pride mixed with concern. I live near the Johnson Space Center and have relatives that have worked in the program as far back as Gemini and Apollo. The space program is much more than a news story to us. To those who think the space program is a waste of money: there is so much innovation and research that goes on behind the scenes that you'd change your opinion if you took the time to look at what NASA has accomplished over the years and continues to accomplish today.
Paul, Houston, TX
Well, I'm relieved it's up there. But they still seem to have this gung-ho attitude to safety. I couldn't believe that after killing two crews they are still happy to launch with a known serious fault.
Chris Hann, Bay Area, CA, USA
Congratulations to NASA on a successful launch. I'm glad to see that some nations still recognise the value of dreaming and aspiring to do great things and inspire their young people. The money spent of spaceflight is miniscule compared to the many benefits. It's sad here in the UK that people are so ignorant and short-sighted with regards to space exploration that we can't see the good that can from it - and then we wonder the younger generations aren't interested in science, medicine and technology.
Victor, Birmingham, England
I watched the launch and was overcome with pride. All the people involved in this great feat have overcome extreme obstacles. This launch showed the world what can be accomplished with great teamwork, ambition and determination. Congratulations Discovery!
D Soni, Nuneaton, UK
Mankind needs a vision. Interplanetary travel is necessary to achieve that end.
Stuart Haines, Calgary, Alberta, Canada
It's time to junk the space shuttle and perhaps "rethink" this whole business of manned space flight for the time being. Think about it, other than as a showy display of national pride, what benefits do any nations get at this time from sending humans into space? Perhaps in the future when we have real goals and reliable "safe" transportation we can start wasting our time and money with such "propaganda flights", but now isn't the time and place for such foolishness.
Charlie, Niagara Falls New York
People always complain that Space programs are too expensive, but do people appreciate how much safer the planet is with them? We can monitor dangerous weather, asteroids, and send TV, Radio, and telephone signals via satellites. Space programs really have helped the planet excel in a positive way, and I'm glad the Discovery is finally continuing what has already been a remarkable feat of engineering.
Tim Hunt (16), Plymouth, England
In these days darkened by the spectre of global terrorism, we seek hope and strength in many places. The fog of war and the wind that whispers the question of "Why are we fighting in the Middle East?' diminish our confidence in our government. Today's launch of the shuttle Discovery renews our hope and faith in our abilities to overcome tragedy and defy adversity. We owe the entire NASA family a debt of gratitude for restoring our faith in the human spirit.
Paul Telfer, Franceville, Gabon
I wish the crew well on the mission, but the shuttle is old and just like any aircraft, it has its life expectancy and this bird has reached it. We need a new way of going to the stars and to ditch the big firework approach to it.
Clive, Dartford, UK
Sure, okay. Maybe the shuttle programme is old. Maybe it should be scrapped for something better. But, it is all we have at the moment. And to all of you here who keep telling us to get rid of it, I haven't heard one of you say anything about putting up any money with us to fund a new programme.
Jon, Atlanta, USA
What Nasa needs is a real life Scotty character to sort these technical issues out.
Paul Collier, London, UK
The truth is that the shuttle concept has proved to be too expensive and technically complex to be the way forward in space. I am pro-space exploration but the shuttle has slowed this to a crawl, and all the best work has been done by probes boosted by rockets e.g. Mars landers, Titan probes etc.
"Space is expensive!" cry the critics. I wish they would angle their criticism at a truly scandalous target. The entire space programme to date has cost less than what the world spends on arms every year. I know which I think is better value for money.
Bernard O. Quinn, Barcelona, Catalonia
The shuttle is expensive, outdated and despite NASA's assurances, its safety is still uncertain; but it's the only game in town. The exploration of space will continue with us or without us; to sit on the sidelines and watch others go up would be unthinkable for an America that prides itself on being a superpower.
Scott Westwood, Port Orchard, WA, USA
Space exploration is essential for the future of all humans. Flying over the Atlantic was at first a risky endeavour and now it is done by millions every year without a thought for the early pioneers and the planes that never arrived.
Colin , Croydon, UK
I do not understand all these people saying that America should scrap the shuttle, and spend it on 'the world'. The US is already the single largest contributor of foreign aid. The US space program has helped everyday life for billions of people around the world, and churned out invention after invention for the world.
Bill Zimmer, Seattle, WA
Congratulations to all those involved in Discovery's return to space! To all the naysayers, next time you are browsing the internet on your PC, take a moment to find out what drove the development of semiconductors that power your PC. Yes, the space exploration that you think is a waste of money!
We were in the parking lot facing east, waiting and whispering to each other. The first person to see the shuttle clearing the trees threw up their hand to point it out and some of the men started yelling, "Go, baby, go!" and cheering. Tears came to my eyes and I held my breath. The Space Program has done so much to improve our lives in the fields of health and science, they further our knowledge of our environment and how our magnificent planet works.
Colleen, Orlando, FL USA
Go Discovery! The future of humanity is in space. As an American living abroad, the lift-off of Discovery is the first event that makes me proud to be American since leaving my country. I hope that this success will lead to the completion of the ISS and the continued exploration of space.
Daniel Valenti, Canberra, Australia
People forget that we belong to this planet Earth, in that our physical bodies are perfectly adapted to survive only on the Earth. We could never survive on other planets without extensive artificial aids. As many have already pointed out, there are many, many more pressing needs requiring resolution and funds should be redirected where they are most needed for our survival on our home planet.
Whatever the administration in the US, it's only NASA that keeps public morale up and at same time keeps the defence lobby in good humor.
Arun Mehta, Mumbai