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Hubble, shuttle, humans and future exploration

Jonathan Amos | 18:29 UK time, Friday, 23 April 2010

Happy birthday, Hubble. It's 20 years since the shuttle blasted off from the Kennedy Space Center to place the famous observatory in orbit.

The telescope's achievements are immense. Few instruments in the history of science have had quite the same "wow factor"; and anyone who looks at its iconic pictures cannot fail to question - just a little bit - their place and significance in the grand scheme of things.

As we've come to expect on such occasions, Nasa has released a suitably stunning image to celebrate the birthday.

The photo shows just a small portion of the Carina Nebula, a colossal birthing cloud for new stars in our galaxy. The pillars of dust and gas which dominate the scene are about three light-years long. Amazing.

Carina Nebula

The version rendered on this page uses data acquired by Hubble's Wide Field Camera 3, which was installed on the last shuttle servicing mission and promises a raft of further discoveries as the telescope moves into its twilight years.

How appropriate that Hubble was launched on the "Discovery" shuttle. Its commander for that mission was Loren Shriver, with whom I managed to exchange a few words this week.

The deployment mission sticks out in my mind because of the issue Loren and his crew encountered with one of the solar arrays.

These panels were supplied to Nasa as part of the 15% European contribution to Hubble and were manufactured in my home town, Bristol, at BAe.

So as you can imagine, there was much pride in that fact... but also a little consternation when the roll-out of one of the arrays didn't go quite as planned.

As Loren recalls, the problem had nothing to do with the arrays themselves, but rather an error in the software managing the unfurling process:

"It all came down to a sensor and a software routine. If the sensor sensed that there was too much tension being placed on the array when it was being unrolled then it would cut off the motors to try to prevent any damage to the solar array. It turned out the software routine was the culprit. It was getting triggered somehow and cutting off the motors when indeed there was no excess tension. Someone worked it out in the end, and a command was sent to the computer from the ground to bypass that part of the software; and then the solar array rolled out to its full extension.
 
"But you know, we had Bruce McCandless and Kathy Sullivan suited up in the air-lock ready to go out and do the job manually. They were almost at vacuum in the air-lock and another five minutes they would have been outside. As a consequence, of course, they missed the release of the telescope because we did it almost immediately."

I promised I would occasionally dig around in the BBC archive for items of interest, and on this special occasion I've pulled up the former BBC science correspondent James Wilkinson's report on this solar array roll-out incident. James catches perfectly the drama of the moment.

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The shuttle is inextricably linked to the story of Hubble. Without the shuttle, Hubble wouldn't have enjoyed the longevity it has; and there's no doubt the observatory has been one of the best advertisements for the reusable spaceplane's capabilities.

But both will soon become history. Hubble's last servicing mission should give it at least four years of further operational life. For shuttle, however, the end is even nearer, with the Discovery obiter itself due to make the last flight later this year.

Both space-borne astronomy and human space exploration are on the cusp of major change - although perhaps not on totally separate paths.

The great space observatories of the future will increasingly be sent a long distance from Earth, to the so-called Lagrangian Points - gravitational "sweetspots" in space where craft can hold station with relatively little effort.

Herschel space telescopeThe advantage of putting telescopes at these locations is that they enjoy very stable viewing conditions - none of the big swings in temperature and light endured by space telescopes positioned much closer to Earth, for example.

Indeed, in Hubble's early years, it had a job keeping still enough to take its snaps because those Bristol solar panels would wobble as they warmed and cooled (BAe Bristol made an improved set of arrays for the first shuttle servicing mission in 1993).

Europe's Herschel and Planck observatories were recently despatched to the Lagrangian Point 2, which is 1.5 million km from our planet on its "night side".

Europe's Gaia telescope will follow them in 2012; and then in 2014, Hubble's "successor" - the James Webb Space Telescope, a colossal machine about the size of a tennis court - will also make its way out to L2.

Just like Hubble, all these telescopes will experience wear and tear, and because they are not close to Earth and have not been designed for astronaut servicing - their missions are highly unlikely to last 20 years.

In the case of the far-infrared Herschel telescope, it's very probable that the observatory will go blind even before Hubble because its special detectors need to be cooled by liquid helium and this cryogen is rapidly boiling off.

All this raises the interesting question: if you gave future L2 telescopes a plug-and-play design like Hubble so they too could be serviced, would you ever consider sending astronauts that far to do the job?

Artist's impression of fuel depotIt's a question I put this week to John Grunsfeld, the astronaut they call "the Hubble repairman". John flew three Hubble servicing missions, including the fifth and final mission last year.

He broadly supports President Obama's new space exploration policy. One of its key features is the so-called "flexible path" idea, which envisages robots and humans going to ever more distant and challenging locations in space.

This might require special stations being set up in space where craft can re-fuel before moving off to their next destination.

John believes this sort of thinking could make L2 servicing missions achievable.

"The fuel depot concept, although I'm not very fond of it, it does require that you have a kind of servicing architecture, perhaps with space tugs that would allow you to go out to L2, robotically at first, and refuel the cryogens to cool the detectors, or fuel the spacecraft themselves to extend their lives.
 
"With Hubble, that's been the huge enabler. The hundred or a thousand-factor increase in the return of exciting science has been the ability to upgrade and repair the telescope. So I think in the future, we will incorporate these features into new observatories but only if the space infrastructure allows it. [The Obama plan] is our opportunity as we redefine that infrastructure for low-Earth orbit and beyond."

If you haven't yet caught our Hubble 20th anniversary audio-slideshow with Professor Alec Boksenberg, you can find it here. Alec is one of the UK's most distinguished astronomers, and was part of the team which designed the Hubble Faint Object Camera, one of the telescope's first instruments (parts also made in Bristol).

At the time of Hubble's launch I had a radio show in Cambridge, and Alec was a regular contributor to the programme. He would update us on the telescope's early performance and how Nasa proposed to deal with its flawed mirror.

We've also asked English Astronomer Royal, Sir Martin Rees, to pen a few thoughts on Hubble. You can read them here. In addition, I've attached another item from the BBC archive - a radio feature produced by my former colleague David Whitehouse. Broadcast on the eve of the launch, the feature looks at what Hubble might achieve.

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I think it's probably true to say the old telescope has exceeded everyone's expectations. Raise a glass.

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  • 1. At 10:19pm on 23 Apr 2010, Bennett wrote:

    Great article, and thanks for the video which I had not seen before. As an aside, it brought a smile to hear Maryland pronounced mary-land, as opposed to the stateside mari-lund. I know, I know, us yanks slaughter the king's English. :-)

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  • 2. At 09:03am on 24 Apr 2010, Ken Appleby wrote:

    Jonathan, you say the Herschel "cryogen is rapidly boiling off." This reads as if there is a problem with the telescope losing its liquid helium faster than expected. Is this the case?

    Also, it would be helpful if you could caption the smaller pictures in your article. I think the first one is Herschel but not sure of the second one.

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  • 3. At 09:03am on 24 Apr 2010, Tommy Jumper wrote:

    A marvelious piece of engineering! Wonderful pictures!
    I often wonder what a scientist or intelligent person living 100 years ago shown these pictures would think of how much we now know about the universe, and that goes for other things of today, we now know an awful lot, and are still learning! Things are also getting very strange, i.e; Quantum Physics!

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  • 4. At 09:35am on 24 Apr 2010, JoeBloggs_snr wrote:

    That picture of the galaxies rather than just stars, through the lens of time is mind blowing. I downloaded a large version of that some time ago and never tire of looking at it. It may not be as dramatic as the one at the top of this page but I think it is more arresting. Just how BIG the universe is!

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  • 5. At 09:41am on 24 Apr 2010, mdammer wrote:

    I was a huge critic of the project because of the high costs involved when Hubble was developed and launched 20 years ago. Now I have to say that Hubble stands out in the way it has made our place in space and the beauty of the universe so visible to everybody. Thank you Hubble !

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  • 6. At 09:53am on 24 Apr 2010, Jonathan Amos wrote:

    @Ken. There is no problem with Herschel; that's just how it works. I've likened it to a "21st Century steam engine". It is the process of boiling and evaporation which cools the bolometers on Herschel to with fractions of a degree of absolute zero, giving the instruments remarkable sensitivity. Read here for more details. So, there is no problem. A similar thing happened to Nasa’s Spitzer telescope. Its helium coolant also ran out over time and it can no longer do the science it was originally designed for (although it is now doing some very fine “warm” observations). On the issue of captions, the software doesn’t allow them! I know, I know. If we can send telescopes to L2, surely we can find a way to put captions on pictures? I shall pass the feedback to my Lords and Masters. Some browsers do allow you to see information retained in a picture’s Alt Tag. Sometimes, if you hover the cursor over the image, you will see a description. But, yeah, Herschel is seen in the test chamber in one image. The other image is an artist's impression of an orbiting fuel depot.

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  • 7. At 10:29am on 24 Apr 2010, aristotles23 wrote:

    AH,beautiful science,the images from hubble are astounding,I never tire of science and the discoveries made.The universe IS a beautiful place and I'm so glad that we can see these images.I'm also glad that scientists can learn more by attempting these miraculous projects.The colonisation of other planets being impossible does not detract from the science of space exploitation..I can only guess what resources we may harvest from space,planets and their moons,asteroids,gas clouds etc.Thank you BBC,more pics please!

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  • 8. At 11:34am on 24 Apr 2010, me wrote:

    The picture is of the eta Carinae nebula.
    Even NASA got this wrongly.

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  • 9. At 12:23pm on 24 Apr 2010, Josh Tumath wrote:

    Some people think that outer space is boring and is just a load of white dots on a black background. These people need to open their eyes.

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  • 10. At 12:32pm on 24 Apr 2010, AdrianC wrote:

    Sorry to be a pedant, but they a Lagrangian points, not Langrangian.

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  • 11. At 3:07pm on 24 Apr 2010, owl1976 wrote:

    Note that for the cost of a Shuttle Servicing Mission to the Hubble, you could build a brand new space telescope - both cost almost $1bn. For this reason, it makes no financial sense to repair either HST or a telescope at L2!

    The real success of HST is in their outreach budget - I wish all telescopes would spend large amounts of money showing off their results!

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  • 12. At 3:57pm on 24 Apr 2010, l33t_sh1tz0r wrote:

    The software induced pictures returned by this taxpayer observatory have indeed shown truly exciting images. The image of the Carina Nebula has pictures in it like those seen in clouds, or mountain faces. There can even be similaer "cloud pictures" found in microscopic images! Three scales, light years, miles, microns....

    The predominant pictures in the Carina Nebula image are of lupine or supine creatures seen from differing vantage points. Amazing to the nines. There are innumerable astronomics images which display "cloud pictures" as there are innumerable clouds...

    These cloud pictures can even be seen in physical scale, such as viewing particular art which has embedded "cloud pictures".... Very particularly interesting to say the least!

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  • 13. At 4:56pm on 24 Apr 2010, CSJP wrote:

    An excellent article! I remember the HST being launched when I was very young and have enjoyed growing up with its returns. I'm far from naive, however it's a shame that so many people apply a cost against endeavouring on such a project. The advancement of our knowledge as a species cannot be compared to a price. The people who condemn such ventures do not, I'm sure, devote all their time and money in helping others with less fortunate circumstances. Humans need to look both within and without in order to grow.

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  • 14. At 5:32pm on 24 Apr 2010, Jonathan Amos wrote:

    @AdrianC: Ah, if only I could spell. I'm indebted, sir, for your Hubble-like vision. I've corrected. All of which reminds me that I wrote an article about Herschel and Planck's journey out to L2 called "The world's most daunting parking job"

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  • 15. At 7:08pm on 24 Apr 2010, BLAZAR wrote:

    I LOOK FORWARD TO ALL THE DATA FROM TELESCOPES IN SPACE . THE DARK SIDE OF THE MOON WOULD BE MY PICK FOR A OBSERVATORY . IMAGERY FROM SUN WAS STUNNING . MONEY WELL SPENT .

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  • 16. At 10:40pm on 24 Apr 2010, The Eye wrote:

    Absolutely wonderful news! Now we can tell the millions of starving children not to worry that they have no food, medicine, education, clothing, or shelter because we have all these wonderful pictures for the text books they'll never see. The billions upon billions of dollars we've spent probably wouldn't have made a difference in silly things like food production, cancer research, or improving the quality of life on earth anyway.
    Is it possible that planet earth's population has distorted priorities? Is it possible that we should be exploring ways to improve the quality of life on earth with these resources before we look for other galaxies to pollute? Perhaps showing these pictures to a starving child will help that child sleep better tonight as it watches a sibling die of starvation. Silly me! I'm being too sentimental!After all, that kid will make good fertilizer for the grain that feeds the cattle that will provide the prime rib dinner for government officials that will enjoy the photos of space over their dinner conversation as well as provide a less depressing conversation topic than starving children.

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  • 17. At 10:57pm on 24 Apr 2010, brobof wrote:

    Some links to the magic mountain picture.
    http://www.nasa.gov/mission_pages/hubble/science/hubble20th-img.html
    http://www.spacetelescope.org/images/heic1007a/
    which *cough* ought to have been in your article Jonathan!

    Whilst I would like to see Hubble get its life extended there are some pretty cool (pun intended) telescopes coming up over the next couple of decades. Pretty PPT here:
    http://www.space.com/scienceastronomy/giant-space-telescopes-after-hubble-100423.html

    Finally the picture you included as a 'fuel depot' is in fact a nuclear powered lunar shuttle from the LUNOX program!
    http://www.nss.org/settlement/moon/LANTR.html
    "LOX-Augmented Nuclear Thermal Rocket (LANTR):
    To the Moon in 24 Hours"
    For the architecture the USA will probably be adopting see:
    [Unsuitable/Broken URL removed by Moderator]
    although all the papers listed under Exploration on
    http://www.ulalaunch.com/index_published.html
    are worth a read... especially the DTAL Lunar Lander!
    Finally whilst you are sorting out picture labels a proper comment editing package would be a help. It's positively medieval compared with the Stateside space blogs. Can you borrow the Grauniad's?
    TTFN

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  • 18. At 11:53pm on 24 Apr 2010, CSJP wrote:

    I'm glad I'm not alone in my opinion, so many people worried about the billions of starving children, they have time and money to post on this topic... As above, I'm sure they don't have technogy in their houses put together using exploited child labour. My point is the world is in a bad state, but we must act on all opportunities, not just those close to home, where science is concerned.

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  • 19. At 00:21am on 25 Apr 2010, Jonathan Amos wrote:

    @brobof. Well, my image library can't be much cop then! Let's try Boeing's instead. The link to the "magic mountain" was supposed to be the first three hyperlinked words "Happy birthday, Hubble", but I'm more than happy to include another link further down. Perhaps, given your two suggested locations, perhaps I should link to the version at "Hubblesite" on the words "photo shows just a small portion of the Carina Nebula". I find hot water and lemon, with a dash of honey, helps with a cough. Cheers. Keep coming back.

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  • 20. At 07:49am on 25 Apr 2010, brobof wrote:

    Oh sorry Jonathon missed that one. My sincere apologies! Perhaps I need some adaptive optics too :)

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  • 21. At 10:01am on 25 Apr 2010, SONICBOOMER wrote:

    To those who say 'what about the starving children' etc, you could axe all the space budgets in the world, but this would not make any difference to the less fortunate of this world.
    Their problems at root are political, most live under either oppressive regimes or ones that are not dictatorial but do have some misplaced priorities maybe, I'm thinking here of India, witness their recent launch failure and much more to the point, engorged military budget-WMD's included.

    Maybe direct your fire against all those African nations with grinding poverty but with leaders who have big swiss bank accounts, major property portfolios worldwide, private jets, because, as they see it, being in charge is 'our turn to eat'.

    Hubble and other science projects lift ALL mankind, I know of a NASA employee who devotes his own time to charitable work, including in Africa, he has found that nothing inspirers kids there to improve themselves through education - a key factor in much poverty - is wanting to be a part of science and space exploration.

    Rather ironic too that objections to science here are posted via the medium of computing, once thought to be just a bunch of eggheads wasting time, then got a massive boost by the need to crack enemy codes in world war 2.

    I would hope those appalled by the needless poverty in parts of the world donate a small nominal amount of their salary, every month, to a reputable charity, if most of us in the rich world did so their resources would exponentially be greater.
    I do, do you?

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  • 22. At 1:21pm on 25 Apr 2010, Jonathan Amos wrote:

    @brobof. The moderators took umbrage at one of your links, which was a shame because it looked like it was going to be an interesting read. Any chance you could put it through a Tiny link conversion and re-submit? Maybe it was the length they objected to.

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  • 23. At 1:24pm on 25 Apr 2010, aristotles23 wrote:

    To those who say that we should not spend any money on research/science etc.until there is not a single starving child on the entire planet..This presumes a concerted effort,a global agreement,co-ordinated and planned by a single international non-political institution.This body would need,up-to-the-minute,hourly,daily,weekly,monthly and annual reports from,in-the-field groups of highly-trained observers.These observers would obviously need full access to every inhabited area on the planet and a means of communicating instantly and reliably with their HQ.This already happens,in an inadvertent and yet sometimes deliberate way,by international journalists being in the right place at the right time.And governments and populations respond(Haiti)The failures of the wealthier countries to completely eradicate poverty worldwide,are more reflective of eternal,inherent,endemics of human existence,("hard-wired"behavioural norms),also,whenever we give as an individual,we inevitably give as a nation,and "we",do not want them to leave us all as poor as the recipients of our charity.Previous centuries saw little or no "social conscience"We've picked up the habit quite well,between the Americans and ourselves we already pick up the tab for the majority of aid/disaster-relief as things stand.I have worked as a professional fund-raiser for numerous charities,not an easy job I can tell you,and,I've had to convince people of the truth that,you cannot develop the science to combat cancer,aids,ebola etc.if you do not spend money on science.Having said all that I recognise that vested interests in this increasingly globalised world,usually seek to maintain a status quo,wherever that is maintaining profit.If we use the fact that so much was spent on blah by blah de blah,we can use that as leverage to ask for more poverty relief,as long as we can rely on the aid/relief getting to the needy and not some tin-pot dictator and his cronies.I suspect it will ALL be a tea-spoon's worth of water to an ocean of inequality...

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  • 24. At 10:45pm on 25 Apr 2010, Andrew Hudson wrote:

    To 'The Eye', your comments are clearly well intentioned but misplaced. The budget of NASA and other space agencies is peanuts compared to other budgets. However these images and all the research and exploration that goes with it allow us to place ourselves in the universe. The sooner everyone knows and realizes this the better. It has allowed us to find out things about our planet and how fragile it is that no generation before has been able to find out plus the study of the stars has led directly to what may be mankind's 'get of jail free' card, fusion power. There are lots of quotes out there about the issues you raise but I would direct you to Carl Sagan's quote of the 'pale blue dot'.

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  • 25. At 09:08am on 26 Apr 2010, Thor wrote:

    Hi,

    Last week I attended a talk given in honour of Hubble's Anniversary at the Dornier Museum in Friedrichshafen/Germany, where one of the speakers was Scott Altman, Commander of the last Hubble Servicing Mission.

    Getting a first hand account of that mission was quite something; especially when he described the problems they faced and how they were overcome:

    Imagine you are the guy in the space suit charged with literally crowbaring a stuck hold-down screw so one of the old instruments can be removed from Hubble. If you apply too much torque and snap the screw, that's it: Hubble's primary mission objective unachievable, billions of dollars in the bin, and untold man-years of work simply gone.

    And all that live on camera with the whole world watching... In the end they just got on with it and it worked out fine, but by then more than a few people would have turned blue from holding their breath.

    What I found great about his story was the fact that even in something as complex as manned spaceflight, where almost every move is governed by procedures, rules and timelines, a little old-fashioned elbow grease sometimes still does the trick...





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  • 26. At 09:34am on 26 Apr 2010, brobof wrote:

    My pleasure Jonathon. Perhaps it was because it directly opens up a pdf file which could be used to exploit a browser weakness.
    http://www.ulalaunch.com/index_published.html Provides the launching point :) for all sorts of spacey goodness by the ULA that reminds this space cadet of OASIS.
    The paper in question (pdf) is entitled:
    "Affordable Exploration Architecture 2009"
    under the Subheading Exploration.

    An 'executive summary' can be found on the NASASpaceflight.com website:
    http://tinyurl.com/qentut
    or http://www.nasaspaceflight.com/2009/09/ula-claim-gap-reducing-solution-via-eelv-exploration-master-plan/
    (Testing... Testing)
    Finally OASIS which IMHO was what they should have used the Shuttle for:
    OASIS the Images
    http://spacecraft.ssl.umd.edu/old_site/academics/484S03/oasis_docs/oasis_pics/
    OTHER FUNKY STUFF
    http://spacecraft.ssl.umd.edu/old_site/academics/484S03/oasis_docs/oasis_docs.html
    OASIS the PDF
    [Unsuitable/Broken URL removed by Moderator]
    (Testing, Testing)
    Glad to be of service!


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  • 27. At 09:45am on 26 Apr 2010, Stuart wrote:

    I fully agree that Hubble is truly one of the greatest space missions ever.
    But why has it never been pointed out in the debate re the future of manned space exploration at NASA that without astronaut intervention (Musgrave, Grunsfeld etc) it would have been $15Bn of space junk !

    In my opinion there has been, is and always will be tasks that are better/only able to be done by astronauts.

    The question is balancing robotic and manned missions correctly, not one or the other.
    It is clear to me that manned missions speak to the 'man-in-the-street' much more clearly (Hubble and MERs excepted) than robotic ones, which generally are for 'Scientific' purposes not well understood outside the immediate space science community.

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  • 28. At 10:49am on 26 Apr 2010, Thor wrote:

    As Aristotles23 others have said: Unfortunately we live in an imperfect world, and to expect to solve all the problems on the ground before we look up to the stars is simply unrealistic and unachievable.

    Why not see the whole thing from a different angle: I my opinion science in general and space exploration in particular are ideally suited to galvanise us into the global community we should strive to be (and in the process eliminate the terrible unbalance between the developed and undeveloped nations, even if it takes a long time).

    Regarding the complaint that money spent on space is wasted, I beg to differ. Look at how much of the wealth enjoyed by the developed/industrialised world is generated by arms and weapons technology.

    Now imagine if you were able to generate the same amount of economic turnover through the peaceful exploration of space. A concentrated effort to colonise the moon or to mine an asteroid, for example, would float entire idustries and in the long term bring untold benefits both on the ground and in space.

    That this sort of joint venture is extremely difficult to pull off is clear, especially considering that it would take generations to achieve. I wonder if mankind will ever become mature enough to realise that only long-term thinking like that will save us from ourselves...



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  • 29. At 10:52am on 26 Apr 2010, TasInParis wrote:

    Maybe 10 years ago I asked a Boeing rep if the James Webb Space Telescope would have a grapple fixture. The answer then was NO, we're are no going back to the Moon let alone the Lagrangian points. Maybe it's worth asking again giving new NASA's flexible path.

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  • 30. At 10:11pm on 26 Apr 2010, Twinkle wrote:

    Happy Birthday to Hubble, an eye on the universe that showed mankind amazing detail beyond our wildest dreams, definitely beats my backyard efforts hands over to view deep space. I love the slide show by Professor Alec Boksenberg, particularly the Orion picture, if you look carefully there is the faintest outline of an astronaut in white hiding behind the gas cloud. To all those involved in Hubble, NASA and any future space exploration I envy you all! What a great job....

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  • 31. At 10:59pm on 26 Apr 2010, brobof wrote:

    27. At 09:45am on 26 Apr 2010, Stuart wrote:
    Actually this has been thrashed to death on the boards I frequent. In truth it would have been cheaper to trash Hubble and build a new one or rather about three to six! That being the cost of mods/repairs _and the shuttle launches_. By building multiples or rather iterations, the cost would have fallen and to complete the savings: these disposable hubbles would have been launched using cheap EELVs. However the counter argument goes:
    - saving Hubble's vision also saved America's 'face.' Value unknown.
    - the budget then (and now) would never have supported a 'production run.'
    - America gained invaluable expertise in delicate on-orbit repairs.

    One final point to note is that Hubble was placed in a non optimal orbit so that it could be upgraded. However I am looking forward to the servicing of the JWST. Now THAT would be a mission!

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  • 32. At 3:12pm on 28 Apr 2010, ghostofsichuan wrote:

    We peek though the crack in the door and are amazed by what we see. One must wonder about the arrogance that humans show toward their won planet when viewing the comings and goings of entire systems. Perspective is something humans avoid.

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  • 33. At 3:18pm on 28 Apr 2010, Robert Lucien wrote:

    Very interesting article, but surely things like servicing missions or space tugs are the perfect place for nuclear thrusters. So in a way that first version of the picture of the tug was oddly appropriate. If only someone could point it out to Obama.

    I'm always one of those sad people arguing to go back to the old space vision. We point out that increasing factors of scale increase efficiency - a rocket that can lift a thousand people costs 10 times one that can lift ten people. A Mars mission using a nuclear rocket or Orion pulse thrust could be done for about thirty billion. -

    (Sorry this is a bit long but I just dug it up for another debate so I thought I'd put it here.)
    America could build an Orion system today. There are several treaties between America and Russia that stop the use of nuclear weapons in space, but a new agreement with the Russians isn't so difficult and the technology could be built as a joint project between the two. If it were hosted by another country like - Britain there would no direct impediment at all.
    Of course there is the NPT, the CTBT and the PTBT but there are ways around all of them - civilian space use could be written into each of them as a new provision. The NPT does currently forbid space use but its inherent unfairness makes it extremely weak and it already desperately needs rewriting anyway. (lookup why India refuses to sign it - over China.) The PTBT was written primarily to stop the surface testing of very large warheads that were putting nuclear material into the atmosphere, Orions pulse units are in a range 100,000 times smaller and actually smaller than some chemical bombs. The CTBT is a problem but is not yet ratified.
    The real problem as always is will, the technical and environmental arguments are mostly minimal - especially if the system is lifted by conventional rockets. In safety terms nuclear rockets including explosion pulse much safer than chemical. Safer, twice as efficient, half the price (for Mars and beyond 1/10 the price), and far more capable. If only most humans these days weren't so cowardly and risk adverse, they hear the word "nuclear" or "progress" and run like headless chickens. Sometimes I hate my species.

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  • 34. At 10:26am on 29 Apr 2010, frogmonkey wrote:

    Oh wow, fantastic article - I didn't know so many new telescopes were being sent up. It's interesting what you say about Herschel's cryogen boiling off thus giving it a short life-span. This seems like a bit of a waste! I'm sure there are many reasons why this design was used but in terms of cost/effort which would be easier: building telescopes that only work for a few years, or ones that can be repaired for many?

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