This website is kept for archival purposes only and is no longer updated.
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| ||||| Thursday, February 07, 2002 - 04:24 am hello u batty boys | |
| ||||| Monday, February 11, 2002 - 06:03 am I don't like it | |
| ||||| Sunday, February 24, 2002 - 10:02 am This is a great time to be alive with all the history that is being made about space. | |
| ||||| Friday, March 01, 2002 - 02:07 pm thank you inspiring me for a skool scins project! | |
| ||||| Friday, March 01, 2002 - 03:52 pm I read to day in my magazine here in Finland,about the fine improvements you are to do with the Hubble,hope it will succseed and that the radiaton dosnot go thrugh the astronouts dresses. Fantastic and fine Good luck! Gitta | |
| ||||| Wednesday, March 06, 2002 - 01:29 pm I would like to know if the Hubble telescope has bionocular vission? If not, can it be fitted with a new pair of glasses. I would also Like to Know if the distortions caused by inner space debris between galaxies can be remedied by Two telescope at a calculated distance apart? | |
| ||||| Wednesday, March 06, 2002 - 03:02 pm you guys are doing a good job keep it up. | |
| ||||| Wednesday, March 06, 2002 - 03:28 pm what are the chances of a spacewalker being hit by a small particle of space debris or rock while servicing the telescope and how is the outer shell of their suits designed to protect them? | |
| ||||| Wednesday, March 06, 2002 - 05:05 pm About binocular vision, no. HST does not have that, nor can it be added. Micrometeorites are always a possibility. One of HST's high gain parabolic antennas has a hole in it due to this source. Past insulation blankets brought home also showed damage like someone shot pellets at the HST. Space suits are designed out of fabric to help keep these hits out. http://www.edcheung.com/job/sm3b/sm3b.htm | |
| ||||| Wednesday, March 06, 2002 - 05:37 pm The chance of a space walker getting hit by debris or metoeroid is inversely proportional to the size of the particle. That is to say the chance of getting hit is higher the smaller the particle. As an example, estimating a typical spacewalker has an area of about 1 square meter and assuming an eight hour walk chances are good (close to 1 in 1)that he could be hit by a particle of 0.015mm diameter. This number is conservative in that it assumes that the astronaut is by himself in space and does not account for any shielding from the shuttle or telescope. Luckily, such small particles are relatively easy to stop. Large debris (>10cm) is typically mapped and tracked. If debris is identified that will pass too close to the shuttle, the shuttle will do a colision avoidance manuever to maintain a minimum safe distance. As for the debris resistance of the suits I suggest you try http://www.spaceflight.nasa.gov/ | |
| ||||| Wednesday, March 06, 2002 - 08:43 pm I was wondering about how Hubble's modular components were designed. Do engineers use "reality checks" like wearing space suit gloves when designing the layout of the components and their connectors? | |
| ||||| Wednesday, March 06, 2002 - 10:22 pm A great number of "reality checks" are done, including full mock-up simulation by astronauts in neutral boyancy tanks (under water). Astronaut ergonomics is a critical part of all design elements for HST since it was designed to be serviced in orbit. | |
| ||||| Wednesday, March 06, 2002 - 10:22 pm yes indeed! a significant part of the effort in designing the HST was spent on making its parts astronaut friendly and replaceable on-orbit. the parts that were so designed are referred to as Orbital Replacement Units or ORUs. i can't remember right now how many ORUs there are on HST, but it's fewer than one would think (like 50 or something). unfortunately, because of budget constraints and other non-technical issues, not all of the parts on HST are ORUs. the PCU fits into this category, and was not specifically designed to be replaced on orbit. it turns out that we can replace many parts that were not designed to be replaced by designing special tools, hard training, and careful planning. | |
| ||||| Wednesday, March 06, 2002 - 11:40 pm Well stated, evil-ed. NASA engineers are to be commended for the their continued ability to make a case for on-orbit servicing. The work arounds by the crew, the excitment of the installations, and the hoopla for a job well done clearly overshadows the outstandlingly expense necessary to design and build the hardware, test it for compatibility with a Host recipient in orbit, pull a shuttle off of the space station assembly, and temporarily transport hundreds of Marylanders to our fair city for the mission. I have heard numbers as low as $100 million per mission and as high as $500 milion per mission. But wait, why am I complaining, my pizza business has not been this busy since December 1999. Go Hubble Go, and keep those Federal monies rolling into Texas. | |
| ||||| Friday, March 08, 2002 - 02:37 am Is the repairs to the telescope something that was expected to wear out or unexpected over the years since it's launch? I would appreciate an e-mail answer from persons read this. | |
| ||||| Friday, March 08, 2002 - 03:30 am Some of each. The solar arrays were expected to be replaced from time to time. Solar arrays on all satellites wear out over time. The Power Control Unit (PCU) was not an item that was expected to need replacement. The Reaction Wheel Assembly was an item that were expected to wear out also, and this is not the first time one one has been replaced. The Hubble instruments were always planned to be replaced over time, not because they wear out, but because new detector technologies make the old ones obsolete -- telescopes on the ground and constantly replacing their instruments, so Hubble needed to do that too. So the Advanced Camera for Surveys (ACS) is the latest in this series. The NICMOS Cooling System (NCS) is a new item, which is in some sense a repair to the NICMOS instrument. The NICMOS cryogenic system used solid nitrogen to cool its detectors, and the solid nitrogen ran out sooner than planned -- the NCS will put the NICMOS back in operation. | |
| ||||| Friday, March 08, 2002 - 04:28 am I am wondering, if some time in the future the Hubble will become obsolete due to technological advances .... and what will then happen to the Hubble thereafter? I aslo wonder what is the cost to keep this project running ... and ultemately is it worth the cost? | |
| ||||| Friday, March 08, 2002 - 06:36 am According to current plan, Hubble will be fetched by a shuttle in 2010 and returned to Earth. I guess you might call that planned obsolescence. Who knows, maybe it'll end up in a museum. I don't know the cost -- the FAQ on hubble.nasa.gov says it cost $1.5 billion to develop the telescope, but I'm sure the project has spent more by now. Hopefully someone who knows the answer to this question will chime in. I guess everybody has to decide for themselves if they think it's worth it. But I might make a few comments. Ground based observatories aren't cheap either -- Hubble costs more, but perhaps not as much more as you might think. And Hubble is capable of things that cannot be done in any ground-based telescope -- in fact, all research done with Hubble is required to be things that can't be done any other way. So what we got for our money so far is over ten years of advances in astronomy and astrophysics that otherwise wouldn't have happened. | |
| ||||| Friday, March 08, 2002 - 06:54 am I live in Atlanta and i viewed the ISS float by. Please advise if the Hubble and the Space Shuttle are floating at a much lower level as it passes by? | |
| ||||| Friday, March 08, 2002 - 07:05 am I would expect that, if you saw the shuttle and Hubble, they would be much closer to the horizon than the ISS. To see when Hubble next can be seen from your location, see the "Where is Hubble" page on this site. | |
| ||||| Friday, March 08, 2002 - 09:56 am Could a second Hubble like telescope be launched to orbit the moon staying in the dark side or at least at the shadow region. When combined images are compared a greater dimensional image should be achieved. Sort of like triangulation, better yet a third (obviously not upgradable version) launched around mars. The cost and weight as well as life expectency would need to be considered, but if hubble stays as main these are lesser child, maybe even specific color spectrum, telescopes it could be feasible. | |
| ||||| Friday, March 08, 2002 - 10:41 am There are some plans, still at a pretty early stage, but multiple satellite telescopes like you suggest. They are called optical interferometers. Some examples have been built and tested on Earth; it will be much more challenging to make them work in orbit. Some more specific comments -- it's not really necessary to keep a telescope out of the sun, because the existing technology for light shielding (like Hubble has) is already plenty good. Also, triangulation was a great technique early in this century, when it was used to gauge distance to the nearest stars. It was done by taking two pictures six months apart, when the Earth had moved about 180 million miles (because of its orbit). Taking pictures from Mars could improve on this technique, though even so there would still be plenty of stars even in our own Galaxy that would be too far away to gauge the distance to this way. | |
| ||||| Saturday, March 09, 2002 - 08:01 am Thank you for this response. The information about orbital delayed photography was so obvious, but it had not ever occurred to me because of earths orbit I didn't think we could see the same objects. But, now with a little thought that just makes too much sense. On a similar note though, many of the Hubble photos taken are with multiple exposures, how far apart are these taken, in respect to time? Many of the images are taken with diferent gasses or temps are these shot within minutes of each other or six months, or because of Hubble's instruments are they taken all at once? Thank you for your time, Keith | |
| ||||| Saturday, March 09, 2002 - 10:15 am Please talk more about The NICMOS Cooling System for Hubble. Being very cold in outerspace why would you need a solid nitrogen cooling system? | |
| ||||| Saturday, March 09, 2002 - 12:03 pm Use Hubble to take a look at the moon and show the lunar rover, lunar module launch pad, flag, and whatever else we left up there in order to show naysayers that we were indeed on the moon. | |
| ||||| Saturday, March 09, 2002 - 01:07 pm Go to this thread:Alot of people don't think you guys really landed on the moon why don't you guys use the hubble to show pictures of the hardware left there. There are a bunch of messages which address this question. | |
| ||||| Saturday, March 09, 2002 - 07:51 pm To Holly, Loosely speaking, in space, you assume the temperature that approaches the object that you are looking at. Thus in full sun, the object can get very hot, viewing deep space, you can get quite cold, and viewing the earth, you can get to around room temperature (that is why the Shuttle usually flies Bay-to-Earth so that the Cargo Bay achieves a manageable temperature). Since even the anti-sun side of HST sees Earth regularly, it is not possible to guarantee a spot on HST that is real cold. Science instruments do not like that. Their performance depends on temperature, so to get predictable images, you need to keep the imager at a constant temperature. In addition, imagers are the most delicate part of the instrument, so you want to enclose them to protect them from damage by micrometeorites, debris, aliens, etc. They are connected to lots of electronics and that would get in the way of them seeing deep space all the time. What you need is a piece of equipment that 'pumps' the heat out of the imager, making it cold, and that 'dumps' this heat out the cold part of HST. This is exactly what the NICMOS Cooling System does. http://www.edcheung.com/job/sm3b/sm3b.htm | |
| ||||| Sunday, March 10, 2002 - 01:38 am I noticed that the end cover on the HST appeared to be in the opened position while the Shuttle was still very close. Is there any danger of cotamination from the shuttle. | |
| ||||| Sunday, March 10, 2002 - 08:08 am Good observation. It is a consideration for close proximity operations. As long as the business end is pointing away from the Orbiter, it is ok. This was more of a concern during the previous mission (3A), as we could have had insufficient gyros to keep HST steady. It is expensive (propellant wise) to go all the way around HST. http://www.edcheung.com/job/sm3b/sm3b.htm | |
| ||||| Sunday, March 10, 2002 - 10:32 am Is there a site where I can go to that will show how the tests went for the replacement parts that were installed. Did all the self test work, were there problems left uncorrected, how well is the new power unit working and when will the first images be available for public viewing? | |
| ||||| Sunday, March 10, 2002 - 09:30 pm Thanks for the info Edward. Looking forward to seeing the New and Improved Images. | |
| ||||| Sunday, March 10, 2002 - 10:40 pm Where did the shuttle launch from? and what was the mission of the shuttle? | |
| ||||| Monday, March 11, 2002 - 01:50 am When are the first pictures from the new and improved scope expected to comeout? | |
| ||||| Monday, March 11, 2002 - 01:15 pm curious, the Space Shuttle always launches from Kennedy Space Center in Florida. This mission is to repair the Hubble Space Telescope. | |
| ||||| Thursday, March 14, 2002 - 05:47 am Hi everyone, I got a question about hubble's replacement.. according to a CNN report; the next one will be placed a million miles out... if that's the case, "How?" are we going to do the same kind of maintenance/repairs on that one as we've just done to hubble? | |
| ||||| Thursday, March 14, 2002 - 10:34 am NGST will have a rocket motor to insert it into its orbit. Due to its location, servicing will be out of the question. Waaaay to far. http://www.edcheung.com/job/sm3b/sm3b.htm | |
| ||||| Thursday, March 14, 2002 - 12:17 pm Inventor, Strictly speaking there will be no replacement for Hubble. For one NGST will primarily look in the infrared spectrum (Hubble looks mostly in the visible) and NGST will not be serviceable. There are no plans to have any serviceable missions after Hubble is brought back. You can find all the space missions that NASA plans at http://spacescience.nasa.gov/missions/index.htm What NASA means by replacement is that NGST will be a large multi-purpose telescope like Hubble. It will however not have the same features as Hubble. | |
| ||||| Thursday, March 14, 2002 - 02:11 pm So many people insist there are U.F.O. aircraft zipping about in space...in all of the Hubble pictures, has there ever been any question of unidentified flying objects? | |
| ||||| Friday, March 15, 2002 - 11:16 am None that I know of. | |
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