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Questions tagged [hubble]

The Hubble Space Telescope (HST) is a space telescope in low Earth orbit with a 2.4 meter main mirror capable of observing near ultraviolet, visible, and near infrared light. It was launched in 1990 and remains in operation (following five servicing missions) as of 2015.

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Can James Webb see Kuiper Belt Objects like 2014 MU69 (Ultima Thule)?

In this paper, we learned that Hubble is the only telescope in the vicinity of Earth that can detect Ultima Thule directly. Hubble will eventually fail, and will be somewhat replaced by James Webb. ...
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How do Hubble, Compton, Chandra, and Spitzer compare in bytes of data collected?

The Great Observatories is a NASA nickname for the four largest space telescopes to date. Each covers a different portion of the electromagnetic spectrum: The Hubble Space Telescope, the most famous ...
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Hubble's one-gyro mode; how does it work for attitude control, stabilization, and slewing?

Space.com's Hubble Space Telescope Apparently in 'Safe Mode' After Gyroscope Failure says: "It’s true. Very stressful weekend. Right now HST is in safe mode while we figure out what to do. Another ...
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Could we see someone walking on Mars from Earth?

Can any telescope be capable to see some one walking on Mars? How much time dilation would there be? What is the theoretical best resolution?
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Why are so many space telescopes placed in LEO instead of at Lagrange Points? And why do we hear about Hubble more than any Langrange-orbit telescope?

Here is the list of every space telescope launched by different space agencies - List of space telescopes. Most of the listed telescopes are placed in Lower Earth Orbit (about 95% of them). It's ...
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What were Hubble's jerk and jounce limits? Did JWST have the same?

From Wikipedia: In physics, jerk is the rate of change of acceleration; that is, the derivative of acceleration with respect to time, and as such the second derivative of velocity, or the third ...
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Hubble gained weight while in space; Which components account for this extra mass?

NASA lists hubbles masses: At launch: 11,110 kg After the last service mission: 12,247kg. That's a 1137 kg increase, about 10%! Which parts are responsible for this increase ? And is there a ...
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2 Hubble telescopes looking at each other in time [closed]

Hubble A (or a huge mirror) is 30 light minutes away looking at Earth and Hubble B. Hubble B is near Earth looking at Hubble A. A laser projector(similar to a movie projector) on Hubble A sends a live ...
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Would it be possible for SpaceX's BFR to return the Hubble Space Telescope to Earth in the future? [closed]

Ever since the Space Shuttle retired, there was an unpopular decision to leave the Hubble Space Telescope until it eventually stopped working, since there was going to be no way to return it to Earth. ...
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Does the Hubble telescope use a “simple” PID-controller for its pointing control system?

I am wondering whether the Hubble Space Telescope uses a "simple" PID controller like this: Or is it using another type of control system that may be much more complex?
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How do those little dish antennas sticking out of the HST track their target independent of telescope pointing?

Almost all the photos I see of the HST show the two small dish antennas at the ends of the two long, opposing booms with the "top" one pointed straight ahead at 12-o'clock, and the "bottom" one at 3-o'...
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Why is there a lid on the Hubble Space Telescope?

What is the lid on the Hubble Space Telescope for?
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What are the economics of upgrading versus refueling satellites?

It is sometimes suggested that fuel produced on the Moon or on asteroids could be launched more cheaply to dock with and refuel for example communication satellites in GEO to extend their operating ...
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Space Shuttle fuel

As I know, Space Shuttle used the same amount of fuel for every mission. And used OMS for finishing orbit. Then how it is possible that, for example STS-1 which hadn't payload and was in roughly 266km*...
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Could the spherical aberration of Hubble have been solved using only software techniques?

When the Hubble space telescope was originally launched, there was a significant error in the way the main lens was ground, causing major spherical aberration. A repair mission was scheduled and the ...
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What savings allowed James Webb telescope to be lighter than Hubble?

Wikipedia states: The telescope has an expected mass about half of Hubble Space Telescope's, but its primary mirror (a 6.5 meter diameter gold-coated beryllium reflector) will have a collecting ...
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Why did the frequency of TLEs for the Hubble Space Telescope drop by a factor of 3 in 2009?

I noticed that the TLEs for the Hubble Space Telescope (HST) are posted almost twice a day. Then I looked back in time and saw that this rate varies quite a lot! The plot shows the time interval ...
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What viewing angles does the Hubble Space Telescope use during its orbit in LEO, avoiding the Sun and Earth?

HST is in Low Earth Orbit. It can of course not look through Earth which at that low altitude covers almost half of the sky. As far as I know it is also never pointed even remotely close to the ...
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Is the Hubble's orbit larger than that of the moon?

I have seen this picture: from "Hubble telescope Photos" and was wondering how they managed to get both the moon and the earth in the same frame for a shot (a relative position/orbit circles would ...
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How is the Hubble main mirror protected from debris?

The Hubble Space Telescope recently hit 25 years in space. It orbits at ~550 km altitude (limited by the altitude the shuttle could reach to service it) and has sustained minor/trivial exterior ...
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Does Earth get in Hubble's way?

Hubble takes very long exposures for its images so that it can collect enough light to see very distant objects. These exposures can be several hours, or even several days, long. I often read that the ...
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Was Hipparcos Satellite really necessary? Can't Hubble do everything that Hipparcos did?

I've been reading about the Hipparcos Satellite recently and it seems it was the first big telescope with precision-measuring devices to accurately pinpoint a star's location in the sky. I know ...
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Could Orion repeat any of the Hubble Space Shuttle servicing missions?

I have a distinct feeling that there's some apparent no-go on the question in the title, but currently can't put my finger on it; For the lifting mass to Low Earth Orbit (LEO), let's assume that SLS (...
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Could the Hubble mirror be used to create a laser to propel solar sails?

Would a space based magnifying lens (such as Hubble) be more efficient than a space based parabolic mirror to propel solar sails?
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Could the Hubble HST be saved by docking with the ISS?

I'm sure it cannot because I've never heard it suggested even on the pretty imaginative space flight communities on line. But the question is why, what makes it a bad idea. Some orbital data I find ...
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The JWST - What happens if/when it breaks?

The James Webb Space Telescope (JWST) project could be fantastic, It has the promise of seeing farther than Hubble, almost to the beginning of our space/time. But, orbiting at L2 - while closer by ...
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Accumulated environmental damage to Hubble main mirror

I'm interested in understanding what effect does long-term radiation and microdust exposure would do to the surface roughness of a high-precision mirror like the one on the Hubble. Since it has been ...
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What is the purpose of Hubble's aft vents?

What is the purpose of the 4 vents at the aft section of the Hubble Space Telescope? The spacecraft is operating in vacuum and the interior of the telescope is devoid of any gas, so venting seems ...
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Why were Nix, Cerberos and Styx discovered later than Charon?

Charon, a moon of Pluto, was discovered in 1978. Today we know that Pluto has three additional moons, but they were discovered 3 decades later? Also, Hubble Space Telescope was in operation since 1990 ...
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Was Hubble really related to spy satellites?

Around the launch of the Hubble Space Telescope, I remember comments in the media that the Hubble may be related to certain espionage satellites. The Hubble was designed and built around the time that ...