Questions tagged [space-telescope]
Questions regarding telescopes in orbit around Earth, such as the Hubble Space Telescope.
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How (the heck) does an astronomical Celescope work? And how did it get its name?
Here's an exceprt from the recent question
The claim may refer to the band labeled U4 in the Celescope Catalog of Ultraviolet Stellar Observations, which refers to a filter with a spectral response ...
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How will China's Xuntian space telescope use its Terahertz capability? THz Spectroscopy? Imaging? Something else?
An Update on the Chinese Space Station Telescope Project Hu Zhan, National Astronomical Observatories, CAS, KIAA, Peking University, On behalf of the CSST Team, ISSI-BJ Workshop: Weak gravitational ...
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Did this satellite streak past the Hubble Space Telescope so close that it was out of focus? If so, how close was it?
The new Nature Astronomy paper The impact of satellite trails on Hubble Space Telescope observations (Kruk et al. 2023) describes an AI-based object classification method used to find satellite trails ...
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How would the "Fluidic Telescope (FLUTE)" next generation telescope make and control a smooth, correct concave optical surface figure in microgravity?
The January 10, 2023 NASA Ames Research Center news item Fluidic Telescope (FLUTE): Enabling the Next Generation of Large Space Observatories discusses a proposed project to study the feasibility of a ...
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Is there enough data in light coming from distant exoplanets for Earth-orbiting telescopes to take a high-resolution photo of it?
NASA’s James Webb Space Telescope has taken very blurry "photos" of exoplanets around distant stars, such as the exoplanet HIP 65426 b, in different bands of infrared light:
My question is, ...
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How does the James Webb Space Telescope achieve a focal length of 131.4m?
How does the James Webb Space Telescope achieve a focal length of 131.4m ?
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Has NASA released any JWST images of Trappist-1? If not, why?
According to JWST weekly schedules (found here), the Trappist-1 system was among the telescope's targets during early July.
The only JWST image of an exoplanet in the Trappist-1 system that I've ...
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How often and for what reasons does Hubble use two different instruments at the same time?
A comment under this answer to ** links to Hubblesite.org's Hubble Shoots the Moon The image, its description and credits are shown below.
As explained, the purpose of the observation was to record a ...
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Does an umbrella reflector telescope exist?
I searched for use of an umbrella mechanism for a reflecting telescope but have not found anything. I was imagining that use of enough actuators on enough umbrella arms would allow fine tuning an ...
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How did this artefact end up in the SIMBAD sky map?
I was randomly looking through the SIMBAD sky map when I came across this artefact. It looks like the projection of a telescopes secondary mirror mount to me but I am wondering how that would end up ...
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Which (if any) space telescope would have worked longer if it hadn't simply run out of helium?
In this answer to Why is the hot part of Webb's MIRI cryocooler in the 300K area? and comments below discusses the helium refrigerator used for cooling JWST's Mid-Infrared Instrument or MIRI.
A ...
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Why is infrared the ideal band to detect the earliest and most-redshifted galaxies? [duplicate]
Was infrared chosen for the James Webb Space Telescope's mission to detect the most-redshifted galaxies and stars in the universe because most detectable galactic radiation emits most strongly in the ...
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Why use a large separate starshade instead of an occulting disk?
The New Worlds Mission proposal has a large occulter on a different spacecraft from the space telescope to block glare from a star to reveal its planets. What is its advantage compared to a disk on an ...
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How does JWST position itself to see and resolve an exact target?
Let's say the James Webb Space Telescope wants to move from observing the Andromeda galaxy millions of light years away to looking at the Trappist-1e planet some dozens of light years away, what ...
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What percentage of visible stars will JWST be able to survey over the next 10 years?
The James Webb telescope is projected to stay operational over the next 10 years. During this time, what percentage of the visible universe/stars will it be able to survey? Of course, technically the ...
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What is the large dim feature near the center of the first James Webb image (of SMACS 0723)?
I was intrigued by the large dim feature (highlighted below) in the center of the first James Webb image of SMACS 0723. Is anything known about it?
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Orientation of the optical telescope assembly in the Hubble Space Telescope
What is the orientation of the optical telescope assembly with respect to the direction of motion of the Hubble Space Telescope? If it happens to be in the direction of motion, does the primary mirror ...
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How did NASA choose "James Webb" as the name of the telescope?
How did NASA decide to name the telescope "James Webb" and not some other name like Copernicus or Ptolemy? The wiki page mentions controversy over the name in the past couple of years but ...
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What is stopping Event Horizon Telescope the size of the Earth’s orbit?
There is a proposal to include a radio sensor in a telescope going to the Sun-Earth L2, getting 120x improvement in angular resolution to EHT. Knowing nothing about interferometry, it seems pretty ...
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How are the occurrence and nature of micrometeoroid impacts on JWST optics identified?
There are been recent news about a larger-than-expected micrometeoroid impact on the James Webb Space Telescope's optics. Apparently this was one of several impacts that have already been observed.
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How far above the galactic plane would a telescope array need to be in order to image the whole galaxy?
I hope this isn't a stupid question, but Google searches are turning up nothing relevant. I was just thinking about how it's difficult for us to determine the true shape and composition of the Milky ...
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What do the letters WHL and LS stand for in the description and name of Earendel star, and other distant objects?
Earendel star's official name includes the abbreviations WHL and LS, as do some other very far-off objects....
What do they stand for?
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How exactly does SPHEREx implement 96 spectral bands with a linear variable filter across its focal plane?
JPL's mission page for SPHEREx says:
The mission will create a map of the entire sky in 96 different color bands, far exceeding the color resolution of previous all-sky maps.
Wikipedia's SPHEREx ...
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In what measure James Webb Telescope "exceeded expectations"?
It is in all the news that the first images of James Webb Telescope "exceed expectations", but in what features? resolution?
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What is "Charged time" in JWST ERS proposals?
In the Early Release Science proposals for the JWST such as this one, there is a "Charged Time" rubric. What is it? What is done during this time?
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JWST First Image With Star 18x - Which image is from which mirror?
The James Webb space telescope first image showing the same star 18 times with the unaligned mirrors is great.
How do they tell which image corresponds to which mirror?
see Photons Received: Webb Sees ...
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How many pixels could an image of Proxima b taken by James Webb have?
I know it's very difficult for the James Webb Space Telescope to image the exoplanet Proxima b without an external coronograph (I have been told by NASA scientists that they don't know yet whether ...
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What does the celestial sphere look like in thermal IR?
The Space SE question JWST detector heat load asks
...what is the heat load from the collected radiation of the main mirrors on the detector, and how does that vary depending on what objects or ...
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What is the smallest (brightest) magnitude that the JWST can safely observe?
Similar to Can JWST be damaged by looking at a bright star?. I'd like to know the brightest magnitude that the James Webb Space Telescope can safely observe without damaging any of its instruments.
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Does a star shaped mirror present problems either optically, or in signal processing over a more nearly circular mirror?
Pure speculation about a future replacement for the JWST that I almost certainly won't live to see.
The JWST's mirror (and then some) would fit unfolded and flat into the Starship's 8m diameter ...
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How does IXPE measure polarization, and why does it have three identical X-ray telescopes?
From The Observatory:
Anyone who missed any of the AAS 239 press conferences can see them on the AAS Press Office's YouTube channel! Here's the full program.
From there I found the Monday, January ...
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Which JWST instrument modes are compatible with observations of the bright trans-Earth planets Mars, Jupiter, and Saturn? Which aren't?
My comment says:
...answers to the Space SE question Can James Webb take pictures of our solar system? In what ways will they differ from/compliment those from Hubble? suggest that at some point JWST ...
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Will the James Webb Space Telescope need re-alignment of primary mirror segments?
I couldn't find an answer to this question.
James Webb Space Telescope will align primary mirror segments and secondary mirror in space.
Question is whether these will need re-alignment during the ...
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How many asteroids were discovered via GAIA? Is there a list?
The ESA Science & Technology video Gaia's asteroid discoveries shows trajectories for hundreds of asteroids that were seen by GAIA, but as far as I can deduce from the extensive notes there, only ...
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Are there any space-based observatories that use interferometry?
Ground-based interferometers such as ALMA have enabled many discoveries. It seems like sending a fleet of small telescopes would be feasible (smaller telescopes are easier to send into space than ...
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Why do satellites appear as streaks in telescope images?
Can you explain me in simple words why the satellite in this telescope image appears as a streak? The exposure time is 1 second.
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Detection of the existence of any extraterrestrial life
We can't see things in "real-time" but we see the "past versions" of the things because it takes time for the light from that object to travel to us. So looking far away means ...
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What new fundamental knowledge could a very, very large optical telescope bring? [closed]
Very large baseline radio telescopes bring many mysteries of the cosmos to us. We build them because they are feasible.
Say, in the future, we could build very large optical telescopes in deep space, ...
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Telescope/s functioning from underground mines
Theoretically and Practically,
Can a Telescope function for the astronomer observed from underground mines? By "telescope" I mean the instrument used by astronomers to observe stars, planets ...
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Why do space telescopes have GRISMS? Why a grating AND a prism for cross-dispersion in slitless spectroscopy?
https://hst-docs.stsci.edu/wfc3ihb lists the page 8.2 Slitless Spectroscopy with the UVIS G280 Grism which contains details of one of the GRISMs of the Hubble Space Telescope (GRISM = Grating + Prism)....
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Why is the Nancy Grace Roman Space Telescope's field of view shaped like a PacMan "ghost"?
The Curious Droid YouTube video NASA's Mega Hubble - The Roman Space Telescope illustrates the shape of the telescope's field of view and the outline has a smile or frown shape. For whatever reason it ...
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What is the nature of the "blind spot issue" in asteroid detection systems?
From Wikipedia's "Asteroid impact prediction" article:
Performance is improving in detecting smaller objects as existing systems are upgraded and new ones come on line, but the blind spot ...
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How much are the benefits of installing a telescope in orbit?
I know that our atmosphere acts like a protective blanket letting only some light through while blocking others. We send telescopes to orbit to get a clearer view of space objects.
I want to know that ...
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What kind of space telescope could best take advantage of orbiting far from the Sun?
While Hubble has provided an astounding amount of science from low Earth orbit, one of the reasons it was put in LEO was to be readily accessible for service and upgrades by the Space Shuttle.
JWST ...
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What would it take to view "the whole EM spectrum"?
I know the EM spectrum goes off both ends, but nearly everything anyone has bothered to use it for has wavelengths between $10^8$m (ELF) and $10^{-12}$m or so (gamma rays). So for the purposes of this ...
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Do telescope measurements (in meters, usually) measure in a straight line, from edge to edge, or follow the curve of the mirror?
Somehow, no site or book or magazine has clarified this question for me....
Perhaps I am an idiot, but,
Is the parabolic primary mirror on the new James Webb Space Telescope (JWST) 6.5 meters from ...
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Why aren't there any images of Sun-orbiting bodies by Spitzer?
Why didn't the Spitzer space telescope shoot images of (dwarf) planets around the Sun, or did it? Even though its primary goal was to detect (the characteristics of) exoplanets, it could have revealed ...
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Can (neo)WISE detect the coolest Y-dwarfs?
The WISE telescope discovered some Y brown dwarfs already. Is the neoWISE mission able to detect even the coolest ones (such as Y9 dwarfs) within five light-years distance? If so, the telescope would ...
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What (if any) capabilities of Hubble are unique and irreplaceable? What can it do that can't be done by any other ground or space-based telescope?
It's impossible to summarize in an SE post the depth and breadth of the contributions to science made using the Hubble Space Telescope.
Above the atmosphere it has
access to an extremely dark and ...
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When thermal infrared space telescopes spot asteroids, are they seeing the body's own thermal emission, or reflected TIR from the Sun?
From the Space SE question Why has the Earth-Sun libration point L1 been chosen over L2 for NEOCam to detect new NEOs?:
above: Profoundly not-to-scale illustration of NEOCam in an orbit around the ...
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