The Hubble Space Telescope vs. New James Webb Space Telescope

Hubble vs. James Webb

I’ve recently found an interesting article over at MIT’s Technology Review about the James Webb Space Telescope and it inspired me to read up on the differences between the planned next generation telescope and the venerable Hubble.

The image above shows first the Hubble Ultra Deep Field (“It is the deepest image of the universe ever taken in visible light, looking back in time more than 13 billion years. The HUDF contains an estimated 10,000 galaxies.” — See here for a high-resolution picture) and in second a simulation of the performance of the James Webb Space Telescope. There’s a clear difference even to the untrained eye.

Hubble Space Telescope

Hubble Space Telescope

First lets look at the Hubble Space Telescope.

It was launched April 24, 1990, and NASA celebrated its 17th birthday recently with the following stats: “800,000 observations, 500,000 images and 100,000 trips around the Earth.” The main benefits of putting a telescope in orbit are that it’s images are not distorted by the Earth’s atmosphere, it is not affected by light pollution and it can observe frequencies of light that cannot be observed well on the Earth’s surface (f.ex. Ultra-violet light, because it is absorbed by the ozone layer).

Hubble Space Telescope #2
Credit: NASA and the European Space Agency, Public Domain image.

Hubble’s mirror has a collecting area of 4.2 square meters (46 square feet) and a diameter of 2.4 meters (94 inches). It can observe on the following wavelength: Optical, ultraviolet, near-infrared.

Hubble Space Telescope #3
Improvement in Hubble images after the first service mission. Credit: NASA/ESA.

The Hubble Space Telescope was designed to be regularly serviced. The first service mission December 1993 allowed the Space Shuttle Endeavour crew to upgrade Hubble as well as boost its orbit. As you can see from the picture above, the upgrade was worth it: The result was much sharper images.

There was at least 3 other servicing missions (see here) but they had less dramatic results than the first one.

The impact of the Hubble Space Telescope on astronomy, physics and science in general is immense: Over 4,000 scientific papers based on Hubble data were published in peer reviewed journals.

Hubble has helped to resolve some long-standing problems in astronomy, as well as turning up results that have required whole new theories to explain them. Among its primary mission targets was to measure [...] the rate at which the universe is expanding, which is also related to its age. Before the launch of Hubble, estimates of the Hubble constant typically had errors of up to 50% [...]

While Hubble helped to refine estimates of the age of the universe, it also cast doubt on theories about its future. [It] uncovered evidence that, far from decelerating under the influence of gravity, the expansion of the universe may in fact be accelerating. [...]

The high-resolution spectra and images provided by the Hubble have been especially well suited to establishing the prevalence of black holes in the nuclei of nearby galaxies. [...]

Other major discoveries made using Hubble data include proto-planetary disks (proplyds) in the Orion Nebula; evidence for the presence of extrasolar planets around sun-like stars; and the optical counterparts of the still-mysterious gamma-ray bursts.

One interesting fact about Hubble: “Anyone can apply for time on the telescope; there are no restrictions on nationality or academic affiliation.” But of course, competition for time on the space telescope is extremely intense.

James Webb Space Telescope

Now on to the James Webb Space Telescope, which is named after NASA’s second administrator, James E. Webb:

James Webb Space Telescope #1

The first thing that jumps at you is how different the design is. For lack of a better technical vocabulary, I’ll say that it is a very “open” space telescope. As you can see on the pictures below, a large part of the space telescope is dedicated to a solar shield. On top of it sits the telescope, and below are solar panels. The telescope will “turn its back” to the sun.

James Webb Space Telescope #2

James Webb Space Telescope #3
Images credit: NASA.

The James Webb Space Telescope’s mirror will have a collecting area of 25 square meters (269 square feet) and a diameter of about 6.5 meters (about 256 inches). It will observe on the infrared wavelength.

The mirror for the new telescope is made out of beryllium, one of the lightest known metals. The material has exceptional thermal properties that allow its optical performance to remain stable at a wide range of temperatures. It is also thermally conductive: that is, it conducts heat across the whole mirror, eliminating temperature gradients.

So the James Webb telescope will have about 5.8 times more mirror surface area than Hubble, and it will be able to observe on frequencies that Hubble can’t (though, on the other hand, it apparently won’t be able to operate on Hubble’s wavelengths).

It is currently planned to launch in June 2013 by a European Ariane 5 rocket. It will be constructed and operated by NASA with assistance from the European Space Agency and the Canadian Space Agency.

The [James Webb Space Telescope]‘s primary scientific mission has four main components: to search for light from the first stars and galaxies which formed in the Universe after the Big Bang; to study the formation and evolution of galaxies; to understand the formation of stars and planetary systems; and to study planetary systems and the origins of life.

Due to a combination of redshift, dust obscuration, and the intrinsically low temperatures of many of the sources to be studied, the JWST must operate at infrared wavelengths, spanning the wavelength range from 0.6 to 28 micrometres. In order to ensure that the observations are not hampered by infrared emission from the telescope and instruments themselves, the entire observatory must be cold, well-shielded from the Sun so that it can radiatively cool to roughly 50 kelvin (−220 °C, −370 °F). To this end, JWST will incorporate a large metalized fanfold sunshield, which will unfurl to block infrared radiation from the Sun, as well as from the Earth and Moon.

Unlike Hubble, the James Webb Space Telescope won’t be on an orbit that takes it around the Earth quickly (for Hubble, that a complete orbit takes 96-97 minutes). It will remain stationary with respect to the earth and the sun at about 1.5 million kilometers from the Earth (in the L2 Lagrangian point).

James Webb Space Telescope #4
The telescope’s location at the Sun-Earth L2 Lagrange point ensures that the Earth and Sun occupy roughly the same relative position in the telescope’s view, and thus make the operation of this shield possible. Credit: NASA.

Mission length for the James Webb Telescope if 5 years, with possible extensions. In fact, it is designed with these extensions in mind.

The James Webb Space Telescope program is currently in the preliminary design phase (Phase B).

In January 2007 nine of the ten technology development items in the program successfully passed a non-advocate review. These technologies were deemed sufficiently mature to retire significant risks in the program. The remaining technology development item (the MIRI cryocooler) completed its technology maturation milestone in April 2007. This technology review represented the beginning step in the process that will ultimately move the program into its detailed design phase (Phase C).

James Webb Space Telescope #5
Full-scale model of the James Webb Space Telescope with some of the people who have been working on it at NASA’s Goddard Space Flight Center in Maryland. Credit: Goddard Space Flight Center/NASA.

I can hardly wait until 2013 to see what marvels of our universe this new tool will be able to uncover.

If you are looking for more, you can read my other Science & Technology posts.


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50 Responses to “The Hubble Space Telescope vs. New James Webb Space Telescope”

  1. Arno Says:

    I would like to point out that both telescopes were built by Ball Aerospace of Boulder, Colorado.

  2. Link-o-rama! « The Sens-Dep Experience Says:

    [...] this is pretty cool. The new Webb telescope certainly has a sci-fi chic thing going on. I’m mainly [...]

  3. Pavan M Says:

    Yes, its indeed remarkable what the Hubble telescope has been able to do in spite of technical glitches. The James Webb telescope promises to be much bigger and better! Its exciting!
    The farther we look out into the space., the farther back we are traveling in time.. The new telescope promises much brighter, sharper and pictures of the universe no one has ever seen till now… The mysteries of the universe are gonna be slowly but surely revealed :)
    Best Wishes to NASA!
    As far as the Hubble is concerned, Good Job!

  4. Robin Says:

    Very interesting comparison write up, it’s short and sweet. The explanation is easy to understand.

  5. Qais Says:

    2013, would be a great year because of the telescopes release, thank you for the people working with the telescope and the efforts they are putting in..

  6. The Hubble Space Telescope vs. New James Webb Space Telescope « Michael Graham Richard « The Journal of the Browncoat Cat Says:

    [...] The Hubble Space Telescope vs. New James Webb Space Telescope « Michael Graham Richard The Hubble Space Telescope vs. New James Webb Space Telescope « Michael Graham Richard [...]

  7. thebrideofthemonster Says:


  8. overslept « blueollie Says:

    [...] Telescopes Here is a cool blog article about the Hubble and the Webb telescopes; there are some spectacular space photos as well. [...]

  9. suelapointe Says:

    Wow! How cool is that?!

  10. Razib Says:

    No wonder, this surely would help the human race to know the space better. – The lives of real people from Bangladesh

  11. The Hubble Space Telescope vs. New James Webb Space Telescope « let’s all blog Says:

    [...] 21st, 2007 Here’s a really interesting article on the new space telescope set to go up in 2013. Over the past couple years, I have enjoyed visiting the Hubble site and checking out all the [...]

  12. cerberus511 Says:

    That is definitely an impressive telescope, especially if the images come back like the simulation. Good article!


    Good Sharing.

  14. Nathalie Says:

    That’s cool.

  15. delusionofgrandeur » Blog Archive » :: Hubble Telescope vs. James Webb Telescope. Says:

    [...] writer Michael Graham Richard has an interesting story on his site comparing the Hubble Space Telescope with the as yet unlaunched James Webb Space [...]

  16. Aspetto « слушайте, космонавты Says:

    [...] comunque vi lascio questo: [...]

  17. Says:

    It’s a tough call. Does the James webb capture giant bees in addition to take great fotos of the cosmos?

  18. Top Posts « Says:

    [...] The Hubble Space Telescope vs. New James Webb Space Telescope [image] I’ve recently found an interesting article over at MIT’s Technology Review about the James Webb […] [...]

  19. Kaida Rose Says:

    What’s the difference between a solar system and a gallaxy? Nice pictures of a solar system.

  20. Treavor Says:

    Amazing. With all those galaxy’s out there, surely there’s life besides that which exists on earth.

  21. links for 2007-05-22 « Hic Sunt Dracones Says:

    [...] The Hubble Space Telescope vs. New James Webb Space Telescope « Michael Graham Richard At 13 billion years away, Hubble Ultra Deep Field (HUDF) contains an estimated 10,000 galaxies. With 5.8 times more mirror surface area than Hubble, James Webb telescope will be able to observe on frequencies that Hubble can’t. (tags: astronomy telescope hubble jameswebb comparison technology galaxy space universe) [...]

  22. A diversion into space telescopes « Lightwater Says:

    [...] occasionally wont to be diverted, see HERE, and THIS blog post falls into this [...]

  23. gaussling Says:

    It would be interesting to know just how close one has to be to L2 to get the benefit of L2. That is, how accurate does station keeping have to be at this position?

  24. yohanan1986 Says:


  25. Kristine Says:

    Sometimes one must just sit… imagine what one cannot see.
    A future awaits. Where? How? Who really knows?
    I think of the writers…dreamers all.

  26. felixwas Says:

    What about the possibility of the mirror surfaces being degraded by impacts from micrometeorites, etc.?

  27. Aquil Akhter Says:

    its all are very interesting……


    Looking well! thanx for sharing!

  29. James C. Webb Says:

    Very cool …
    I am James C. Webb (not the)
    And I approve this telescope.
    Do you say ‘GodSpeed’ for an unmanned space object?

  30. Bahtir Deliu Says:

    Very good, i love it, i wish i could c it for real.

  31. Phillip Coffman Says:

    With regard to Arno’s comment of May 20, 2007: Arno, ever hear of Perkin Elmer?? Ball Bros. had as much to do with the HST Optical Telescope Assy (OTA) as Perkin Elmer had to do with the Webb Telescope Assy. Namely; none! Ball did produce the temporary fix for the HST Optics problem known as the COSTAR. A trivial effort compared to the OTA.

  32. xp95 Says:

    wow with the teliscope going up we might be able to find new life out there. now that would be the day :)

  33. kyleisthebest Says:

    not gonna work

  34. catcherinthesky Says:

    I wish Carl Sagan would have been able to see it…. The Hubble was an amazingly successful project. We can only imagine the Webb’s impact on the knowledge of the human race. I wish everyone involved the very best of luck!

  35. BaTyA Says:

    На таких громких заголовках и подобной шумихе можно делать и не такие успехи :)

  36. spacedragon Says:

    i am rapt with the james webb space telescope. i have a deep interest in space and space technology, i am not a highly educated person but this is my passion and hobby. my family has no interest in space so i dont get to share with other likeminded people often. it is truly amazing what mankind can do these days and i feel i was born in the wrong era lol. 200 or even 1000 years from now would have done me fine but oh well lol. imagine what advancements we could have acheived in space if the human race was not so hell bent on killing each other. we could be light years ahead by now. imagine all the money invested in war instead invested in space wow. anyweay love the james webb and cant wait for the next era of secrets unraveled.

  37. spacedragon Says:

    on another subject has anyone heard anything new about the next generation shuttles or are they just gonna stick to the revamped appollo cans?

  38. spacehelper Says:

    I know this will help to our experts to know all space details and they may know the past of the galaxies and out universe

  39. haakon Says:

    hi there man

  40. guitargazer Says:

    Why does it have to be named James Webb? Nothing against the guy, it’s just that he is not very known, etc. Newton.

  41. gene k. norman Says:

    For all the knowledge of man common sence is nowhere, all the rocks, particles of dust,comets, planets with there moons, stars, black holes, galaxies in all the vastnest of space you can believe everything was once smaller than an atom. There is another answer, believable with common sence, making sence, logical, the creation of this universe as like all others is remarkable,but has happened before, will happen again and is explainable. We are to believe (even though light cannot escape a black hole beacuse of to much mass) everything was smaller than an atom, be for real, just how much can be compressed before you say hey that doesn,t seem right. How smart are we to look so stupid.

  42. John B Says:

    Just a couple of intriguing points:
    1. If HST can see back to 13 billion years ago, why is JWST so much
    larger – looking back beyond ‘The Big Bang’ perhaps ?
    2. At the L2 location it will be impossible to manually service this item – as every eventuality should be catered for, such as a mishap when
    being deployed, has a robotic ‘repairman’ been devised ?

  43. yahye Says:

    thats realy cool

  44. garywilson Says:

    Humankind can think and create such wonders, and understand and conceive of such wonders. Will we ever get past the horrors and cruelty we inflict on each other?

  45. bob Says:

    hi this is BIG BOB!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    i like the idea of a new space telescope but i do like hubble

  46. Atul Says:

    This is really exciting but i guess we are not going to see start of galaxy but we are going to face some new questions? which we never thought

    But this is some thing we will find out in 2014 till the time lets wait

  47. weldon Kirui Says:

    Im anxiously waiting for the launch of JWT in June 2014. the project is amazing. i am sure with JWT we will soon realise that we are not alone in the universe. there is life out there in those distant galaxies. Ever heard of Big Bag, big crunch and Big bounce. There was big bag,when the universe exploded creating the stars we see,in the big crunch, all the galaxies will collide and life destroyed. After this there will be creation all over again. Kudos to all scientists working on JWT.i am told that the tiny distant star that glows like firefly when see with naked eye will be magnified by JWT some 10 billion times!!!!

  48. New Space Telescope at Deep Space Telescopes Says:

    [...] Mouse here for Related LinksThe Hubble Space Telescope vs. New James Webb Space Telescope [...]

  49. Joseph Kent Says:

    Will the JWT be able to image extra solar planets; or will we continue to rely on the light-reduction methodology of Kepler?
    Joseph Kent

  50. Brojoh Says:

    Imagine the JWT needing a ‘Hubble’ type tweek to fix a minor problem; to improve its exact location or to clean up any micrometric damage as it ages; impossible with our current technology , so what will NASA pay for a solution to its servicing problem ?

    All this presupposes that the launch is successful.

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