Questions tagged [space-telescope]

A telescope placed in space, typically for the purpose of avoiding atmospheric distortion, background light, and attenuation of light by the atmosphere.

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3 answers
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Why would the James Webb Space Telescope need adaptive optics outside the atmosphere?

Adaptive Optics is generally used with ground telescopes to correct for atmospheric distortions or seeing. Right now it is used mostly in the infrared but is starting to be used in longer visible ...
10 votes
2 answers
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Interesting diffraction pattern on JWST composite false-color image released today (July 11) at Biden preview - how does this arise?

There was an earlier question on the diffraction pattern in the Mar 16 test image that was mainly explained by the hexagonal shape of the individual mirror segments. Today's image has similar ...
8 votes
1 answer
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Why aren't off-axis reflector telescopes more popular for space telescopes? Have there ever been any?

It seems that: The light gathering capabilities would be slightly better without the blocked aperture (clear aperture is a premium for fairing-limited space telescopes) The diffraction patterns from ...
0 votes
3 answers
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How would a repair of the JWST proceed if it were ordered regardless of the cost and technical hurdles, depending on when/how it fails? [closed]

I have heard people speaking about how, unlike Hubble, the James Webb Space Telescope is "one of a kind", "not designed to be repaired", "not serviceable", and the like, ...
2 votes
1 answer
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Why a polar orbit for TWINKLE?

TWINKLE will use a 0.45 meter telescope to record spectra of stars transited by their exoplanets. By looking at tiny changes in the spectrum as the planet's atmosphere moves in front of the star, they ...
13 votes
2 answers
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What caused the JWST Instrument Radiator temperature to start cooling faster on day 34?

As shown on the temperature plots, the D-Instrument Radiator temperature was slowly dropping after sunshield deployment. Around day 34, however, the temperature started to decrease faster than before....
3 votes
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What can/do astronauts look at with the portable telescopes aboard the ISS?

I would like to know what will be the visibility from the portable telescope aboard the International Space Station. What could they potentially view, and what are (at least some of) the things they ...
5 votes
3 answers
686 views

Curvature of the JWST mirrors

The JWST has four mirrors. The large primary mirror made of 18 hexagonal mirrors The secondary mirror The fixed tertiary mirror The flat fine steering mirror I found very little information about ...
4 votes
1 answer
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When will the jwst python library have live data for the general public to work with in its data pipelines?

The Space Science Telescope Institute has put out a python library called JWST for science observations from James Webb Space Telescope. When will the general public be able to look at "live"...
4 votes
1 answer
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How does the James Webb Space Telescope take images with individual mirror segments?

It says here (and elsewhere) that during mirror alignment the James Webb Space Telescope will take $18$ “individual images” of a star, “one from each mirror segment”. I’m wondering how this is ...
37 votes
3 answers
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Why should the James Webb Space telescope stay in the unstable L2?

We all know that James Webb Space telescope is planned to be launched in 2018. It has been decided that the orbit of JWST will be elliptical around the Lagrange point L2, which has been declared as ...
2 votes
2 answers
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How can the proposed LUVOIR space telescope slew to different directions while keeping the sunshade in a fixed orientation? What compensates?

In this answer to Why does JWST have such a big Blind Spot? I mention that it moves as a rigid body; in order to change the direction the telescope is pointing the whole spacecraft slews, including ...
12 votes
1 answer
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Could JWST operate with failed or partial wing mirror deployment?

I have not found any information about contingencies for failed wing mirror deployment. Could JWST operate, and at least partially fulfill its scientific mission, with only the center core mirror, ...
9 votes
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Why the thermal imaging of Mercury's surface requires a telescope on a jet flying through an eclipse?

The NASA News Feature Chasing the Total Solar Eclipse from NASA’s WB-57F Jets describes two telescope-equipped NASA jets that will fly fast enough to spend about 7 minutes in the Umbra (totality) of ...
6 votes
2 answers
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What will happen to JWST after its 10 year mission?

JWST launched recently. https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Orbit JWST needs to use propellant to maintain its halo orbit around L2, which provides an upper limit to its designed ...
8 votes
1 answer
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Why have JWST in a Sun-Earth L2 halo orbit?

What is the main reason JWST will be in a halo orbit around the Sun-Earth L2 LaGrange point? There have been questions on this site that ask Why won't JWST deploy in LEO where it is potentially ...
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How will JWST see beginning of universe? [closed]

The light that is supposed to come from far away distance galaxy, that will reach James Webb Telescope, won't it have already passed earth? BBC puts out this explanation in this article. Won't the ...
5 votes
1 answer
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Are they already planning a successor to the JWST?

Hubble has been flying for 30+ years. JWST took 10 years to fund and build. But given its 10 year (if we're lucky) life expectancy, I assume its successor is already on a drawing board somewhere.
2 votes
1 answer
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For JWST's "29.5 days of terror" before orbital insertion, unfolding the sunshield is the scariest for me. When is this scheduled to happen?

At what date and time UTC is JWST's unfolding of its sunshield scheduled to begin? At what date and time UTC is confirmation of success expected if all goes smoothly?
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Where is this "clusters of pearls" design for a solar gravitational lensing telescope discussed in detail? Who's developing this?

In What might the first deep space telescope using the Sun or Jupiter as a gravitational lens be like? I speculated that the detector for a gravitational lens telescope would be a big array of ...
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What might the first deep space telescope using the Sun or Jupiter as a gravitational lens be like?

@SteveLinton's nicely written and sourced answer about using strong gravitational lensing by the Sun or even Jupiter as a kind of telescope to resolve the surfaces of exoplanets is really interesting, ...
5 votes
1 answer
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How are JWST tanks baffled to dampen slosh?

After JWST slews to a new orientation, it then needs to “settle” sloshing fuel in the tanks before Fine Guidance System (FGS) can acquire the new science target. The time needed for slewing, settling ...
9 votes
1 answer
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How would NASA confirm the James Webb Space Telescope is undamaged after the clamp release incident?

Would NASA point a space telescope at something far enough away in a clean room to confirm that the telescope is functioning correctly before launching it into space? Is there some optical technique ...
4 votes
1 answer
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Where can I read about the other 17 telescope proposals that NASA’s Astrophysics Explorers Program didn't accept in 2019?

Update: Per @DH's comment: Possibly nowhere, except for brief and oftentimes inscrutable summaries. The summaries have to be publicly releasable. Proposers often do their best to make the publicly ...
8 votes
3 answers
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Is it possible to create a geostationary surveillance telescope?

Is it possible to create a telescope in geostationary orbit, with real-time video from any country or area? Some applications could be: Monitoring of burning and deforestation; Residential/industrial ...
3 votes
1 answer
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What will Taiwan's NSPO put in orbit around the Moon in 2025? How will it get there? What will it do?

The Taipei Times article NSPO head eyeing 80% autonomy of satellite industry says: Following the six-satellite Formosat-7/COSMIC-2 constellation’s launch in 2019, weather observation satellite Triton ...
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1 answer
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International space station(ISS) viewed from planet earth

Is it possible to view International space station (ISS) using sophisticated Telescopes from planet earth?
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Can Interferometery be Used to Shorten the Solar Gravitational Lens Focal

The solar gravitational lens's focal is around 550 AU which is very far. Can we send a few telescopes that will stop midway (let's assume 150 AU) to collect the light and work as interferometry?
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1 answer
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Space telescope protective gear?

Is there any history of damage to space telescopes from meteoroids etc? If there is, would the James Webb be going up with any kit for detecting small bodies in near proximity (inside the L2 point) ...
5 votes
1 answer
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Are spacecraft star cameras ever used as scientific instruments for research?

There are quite a lot of spacecraft that have been up there a while and a lot of them have star cameras for attitude determination and for attitude control. Space telescopes (both heavenly and Earth-...
2 votes
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What are Spectr-R's major contributions to radio astronomy that could not have been done from Earth?

R. I. P. Spektr-R Spektr-R Spektr-R (37755, 2011-037A) is a Russian radiotelescope spacecraft in a very high orbit around the Earth. It's orbit is cis-lunar with ...
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1 answer
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Why was the Rossi X-ray Timing Explorer decommissioned in 2012? Why wasn't it deployed another ~100 km higher where drag would have been a lot less?

The Rossi X-ray Timing Explorer (1995-074A) was an incredibly prolific space telescope between 1996 and when it was decommissioned/deactivated on January 5, 2012. It reentered the atmosphere soon ...
1 vote
1 answer
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What is NEOCam's (now NEO Surveyor) strategy for scanning the sky? Need to consider in which coordinate system?

In Survey Simulations of a New Near-Earth Asteroid Detection System it can be seen that Infrared astronomer Amy Mainzer gave the scanning strategy of the horizon in a paper, but I am very confused ...
4 votes
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Telescope in a crater? How different are the bowl shapes?

When building large stationary single-dish radio telescopes, one of the constraints to location is that the landscape should already have approximately the right shape, cutting down on construction ...
1 vote
2 answers
387 views

Why has the Earth-Sun libration point L1 been chosen over L2 for NEOCam (now NEO Surveyor) to detect new NEOs?

above: Profoundly not-to-scale illustration of NEOCam in an orbit around the Sun-Earth libration point L1, about 1.5 million kilometers from Earth. Presumably Sun-shield and Earth-shield block light (...
7 votes
1 answer
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How was the Moon's first telescope used? (Apollo 16)

From Gizmodo's There's Poop on the Moon list of things left on the moon: This gold-plated telescope that was the first tool used to make astronomical observations from the surface of another ...
2 votes
1 answer
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What will (likely) be the first separately-orbiting coronagraph to be deployed in space?

Traditionally a coronagraph is something that blocks the bright disk of our Sun to make it easier to image the much dimmer corona. The first coronagraph is of course the Moon; during a solar eclipse ...
5 votes
0 answers
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Is the Hubble Space Telescope on its last legs, or "back to normal"?

Hubble was designed to accommodate regular servicing and equipment upgrades while in orbit. Instruments and limited life items were designed as orbital replacement units. Five servicing missions (SM 1,...
17 votes
1 answer
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Aren't the mirrors of the James Webb Space Telescope too unprotected?

I've looked at the design of the James Webb Space Telescope and I got curious about something, some years ago, it seems that the international space station was hit by micro-meteorites. I'm wondering ...
7 votes
2 answers
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What exactly gives a larger field of view to the donated "spy" telescopes that NASA may send to Mars? How much larger?

This answer to Could one of the interstellar probes discover Planet IX by accident? links to Space.com's NASA May Launch Donated Spy Satellite Telescope to Mars which says: An unexpected gift The two ...
5 votes
1 answer
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Will WFIRST and JWST be able to resolve each other?

The James Webb Space Telescope is scheduled to launch in 2021 and be put in a halo orbit around Sun-Earth L2 soon after. The plan for the Wide Field Infrared Survey Telescope is a launch perhaps ...
2 votes
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How bright would electrostatically suspended dust above the lunar surface be? Has it ever been measured?

@TomSpilker's answer to Is there any Scientific Benefit to the Lower Albedo levels on the Darkside of the Moon? mentions the potential effect of dust from the lunar regolith being slightly ...
3 votes
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Will the James Webb Space Telescope be able to see the Spitzer Space Telescope (assuming...)?

Space.com's NASA's Spitzer Space Telescope is no more. Here's what's next for infrared astronomy. says: The best infrared eye in the universe† has closed, and scientists will need to wait at least a ...
3 votes
1 answer
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Which spacecraft far from Earth have arc second resolution cameras that could measure Betelgeuse's position?

All hands on deck! We have to measure the distance to Betelgeuse ASAP because Recent headlines saying that Betelgeuse is much closer than we thought, and they point to Standing on the Shoulders of ...
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1 answer
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How will the "fleet of small asteroid hunters" proposed by the B612 Foundation & York Space Systems work?

The June 2018 news item in Science To find small asteroids that could hit Earth, private foundation embraces small satellites says: On 10 May, B612 announced a partnership with York Space Systems, a ...
2 votes
1 answer
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What is the name of the new NEO searching telescope "heavily based on" NEOCam? (now NEO Surveyor)

Space.com's NASA Wants a New Space Telescope to Protect Us All from Dangerous Asteroids quotes "Thomas Zurbuchen, associate administrator for the Science Mission Directorate" several times, ...
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How will NEO Surveyor manage 82 gigabits/day of data? How will it process it, what fraction will be sent to Earth and how it compares to TESS & GAIA?

Wikipedia says says: NEO Surveyorformerly called Near-Earth Object Camera (NEOCam), then NEO Surveillance Mission, is a planned space-based infrared telescope designed to survey the Solar System for ...
3 votes
1 answer
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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. ...
2 votes
1 answer
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Roughly what fractions of the time did Skylab spend in Earth-oriented and Sun-oriented attitudes?

The Introduction section of NASA Technical Memo TM-X-64628 Angular momentum desaturation for Skylab using gravity gradient torques begins: The Skylab Apollo Telescope Mount (ATM) experiments require ...
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What causes GAIA rotational axis to precess the way it does? How exactly is this accomplished?

The GAIA spacecraft rotates at 1 degree per minute about its axis, scanning two telescopes looking 106.5 degrees apart but imaging on the same focal plane around a circle every 6 hours. The rotation ...