Questions tagged [telescope]
Questions related to the physical instruments for astronomical observations.
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What are the technological advancements that made it possible for modern large telescopes to work with alt-az mounts instead of equatorial mounts?
The video Earth's Rotation Visualized in a Timelapse of the Milky Way Galaxy - 4K (linked below) and discussion below this answer to Why does a timelapse video of a stationary Milky Way make the ...
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When might Rowan-Robinson's planet be discovered or disproved?
A month ago Michael Rowan-Robinson discovered three dots on old images of the sky which may or may not be an undiscovered planet (that's not identical to Brown's and Batigyn's hypothetical planet). I ...
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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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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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What should I look for in a first telescope for a child?
I'm in a situation that I think many parents find themselves: my son has said that for Christmas he wants "a telescope so that I can see the planets". Which is cool, and I certainly would ...
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New to Astrophotography
I just had a quick question on my telescope I recently purchased.
I have a Canon Rebel XTi and I paired that with the William Optics Guide Star 61 Guidescope.
The Specs on the Scope are:
Guide Scope ...
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Could someone explain what is wrong with my telescope, and what should I be able to see with it?
In January of 2016, I received my first telescope, through Astronomers Without Borders. It was and is my first telescope: an AWB 130 Newtonian tabletop telescope with a 650mm focal length and a 130mm ...
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How big would a telescope have to be to get a good look at the nearest neutron star?
It's my understanding of observational astronomy that the size of a telescope limits its effective angular resolution, which is why scientists needed to use radio telescopes all over the globe to look ...
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Which one is better for both the beginner dad and the 7-yr old? Sky-Watcher 130P or Celestron StarSense Explorer 114AZ
I am looking for a beginner scope for myself and my 7-yr old. She has been asking for a telescope for some time but I don't know how immersed she would be, once bought. So, I want something which can ...
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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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How is resolution defined?
So I'm looking at a 1 meter square object in my digital camera. What size of pixel is considered fine enough that the object is considered to be resolved? Obviously a pixel size of one meter squared ...
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Would a telescope substantially away from the ecliptic plane improve TNO detection?
There have been lots of new TNOs found in the last decade.
Would a telescope far from the ecliptic plane be useful to image them, and spot new ones?
What about planet nine, assuming it exists: would ...
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How has the price of an amateur telescope 8-inch, f/8 finished, aluminized mirror varied over the last fifty years?
During a discussion in The Observatory I was remembering that an 8-inch telescope mirror, polished and aluminized, cost something like \$100 to \$200 US in the mid 1970's.
Just now I've seen an add in ...
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How does eyepiece exit pupil diameter affect image clarity and viewing experience?
This answer to Not Able to View Objects with Barlow Lens includes a calculation of exit pupil diameter as a way to address the limits of useful magnification when observing planets with a small ...
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Not Able to View Objects with Barlow Lens
I am new to using a telescope and am having a hard time using a Barlow lens. I was able to find Jupiter multiple times using a 6mm lens with a telescope that has a D = 60mm and FL = 700mm. I am very ...
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How exactly does NEOSTEL's fly's eye telescope's secondary mirror array split the primary beam among sixteen cameras?
Wikipedia's NEOSTEL says:
The Near Earth Object Survey TELescope (NEOSTEL - also known as "Flyeye") is an astronomical survey and early-warning system for detecting near-Earth objects sized ...
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I'm considering buying a telescope, which type should I choose?
I am considering buying a telescope for amateur viewing. I am planning to view the stars from my backyard, which is in an area with reasonable light pollution (most of Orion's primary stars are ...
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Advice for next steps with astrophotography
Over the last year, I have started to take up the hobby of astrophotography. At the moment I have been focused on planetary astrophotography. Up until now I have been using a Celestron 5SE telescope (...
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How come I can point to two places with telescope and have the same coordinates?
Absolute beginner here. I read through the telescope manual, watched many videos, and got a pretty decent understanding of DEC and R.A.
However, I don't understand one thing (where theory doesn't ...
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If Proxima Centauri was replace with a quasi-star, would our telescopes be able to see it in fine detail?
Quasi-stars, if they ever existed, were stupid big and stupid bright; many times bigger, brighter, and more massive than any star supported by fusion can be. There's no question that it could be seen ...
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Can large scientific telescopes observe the Moon without being damaged?
When I look at the full Moon through my 10cm telescope, it is so bright that it hurts. Can large scientific telescopes observe the moon at all? Does that require special protection equipment? Or ...
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Tracking deep sky objects
I have a Celestron Astromaster 130Eq. I saw all the planets in our solar system and quite satisfied. Now I am in the hunt for DSOs, but living in a city is a disaster for tracking some good-for-...
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Schmidt corrector plate on a Newtonian = Schmidt Cassegrain?
Went on with a wide range of telescopes and its mechanics. To my understanding, the only change in the optical function in Schmidt Cassegrain telescope is a Schmidt's corrector plate in front of an ...
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Not getting quality images in telescope
I have a Newtonian telescope (Celestron 130 eq) with 5.2 inch (~132 mm) aperture with 650 mm focal length, Spherical mirror. And having 4mm, 10mm, 12.5mm, 20mm,20mm (erecting eyepiece), a 3x and 1.5x ...
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What is the difference between a Cassegrain telescope and a Gregorian one? Which one is better?
Of the three giant (or 'Extremely Large') new telescopes being built, the Thirty-Meter (TMT), the the Giant Magellan (GMT) and the Extremely Large Telescope (ELT), only the Magellan, from what I ...
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How to determine the color term for a filter with a systematically bluer offset than the standard
This is a hypothetical scenario in an attempt to test my understanding of the color term when performing photometric calibrations:
Imagine we are observing stars through a B filter with an offset ...
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Would Atlas Pro's prediction about the color of plant in Kepler-186F work as a biosignature to search for life?
The Atlas Pro video that prompted this question is this.
Tl;dr: it is argued that due to the different spectrum of radiation emitted by Kepler-186 and what is known about the evolution of ...
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Can you advise on the construction of a large segmented primary mirror (hobbiest)?
I am interested in experimenting with the building of a large parabolic primary mirror constructed from 4" hexagon mirrors mounted on a "rough" parabolic surface with either 3 screw ...
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A new (radio) neutrino telescope in Greenland?
I just stumbled upon ScienceMag news from July 14th, 2021 which says:
By placing hundreds of radio antennas on the ice surface and dozens of meters below it, they hope to trap elusive particles known ...
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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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If the visibility function is the Fourier transform of the sky brightness distribution, why do you need the dirty beam and dirty image to find it?
In radio astronomy, the dirty image is equal to the inverse Fourier transform of the uv-plane coverage times the sampled visibilities. The dirty image is also equal to the convolution of the "...
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Is there a complete guide on how to use telescopes?
tl;dr As said by @uhoh in the comments, is there A Big Book of Telescopes? i.e: Is there some kind of media that gives a complete treatment to telescopes?
I am relatively new to Astronomy.SE. I wanted ...
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What can I see with different apertures?
I'm looking to buy a telescope, and every mainstream website says that aperture is the most important factor, and buy the largest telescope your budget can afford. However, a website I found offering ...
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How common are telescopes with the finder scope on the right side?
Are there telescopes where the finder scope is mounted on the (upper) right of the body? Are they common? If not, are there any ways around this (e.g. can I mount a lightweight telescope "...
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Can a hydrogen bomb explosion be seen from every distance?
When we use the strongest optic telescope available, how far from Earth can a hydrogen bomb explode in space and be visible for this telescope?
Is there a fundamental limit to this distance? Even for ...
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2001 VB - when will it be reacquired?
2001 VB's orbit is poorly known but has a two-in-a-billion risk of a collision with the earth in 2023.
Assuming that it were on a collision course, when would it be likely to be reacquired? Which ...
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Can the transit of satellite in front of Sun be visible in 10-inch telescope?
I have 10 inch Sky-Watcher telescope and I would like to know if a satellite passing in front of Sun can be visible. Suppose that satellite's angular diameter is 1˝. Yes, I know the formula $\theta=\...
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Would a possible accretion disk around a primordial black hole 500 au from the Sun be visible in present telescopes?
If the hypothetical two-inch black hole 500 au from the Sun had an accretion disk, might current telescopes detect it already or do we have to wait till the Vera Rubin Observatory starts work?
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Why did the famous Multiple Mirror Telescope (MMT) get rid of them and become the Massive Monolithic Telescope?
Popular Science's 2016 article The silliest names scientists have given very serious telescopes... Ranked! says:
Arizona’s MMT Observatory used to house the Multiple Mirror Telescope. In 1998, ...
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How much of M87 can i see with an amateur telescope?
I was reading about M87 and how it is possible to see it's relativistic jet with an amateur telescope.
About a year ago i impulse-bought a telescope (model: Celestron CE21049 powerseeker 127EQ).
I'm ...
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Can we get a picture of Oumuamua with Hubble Space Telescope?
Can we get a picture of Oumuamua with Hubble Space Telescope?
If not, what are the reasons?
Answers why other telescopes might fail to get a picture of Oumuamua are welcomed as well.
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Safety while using a telescope to view a total solar eclipse
I have an 8-inch reflector telescope and a solar filter that goes on the front aperture to view the Sun (most recently to view the transit of Mercury). If I were to use this telescope during a total ...
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Do telescopes exist that reflect the incoming light more than three times along their length?
Refractors only use the length of the telescope once, reflectors twice, catadioptric telescopes like those of the Schmidt-Cassegrain design three times. Have telescopes been built that reflect the ...
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Do triple or more times reflecting telescopes exist?
Refractors only use the length of the telescope once, reflectors twice, catadioptric telescopes like those of the Schmidt-Cassegrain design three times. Have telescopes been built that reflect the ...
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How do I design a good telescope to observe nebulae and other deep sky objects [closed]
How can I make a good telescope that is powerful enough show nebulae and other deep sky objects ? (consider low budget build)
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Given telescope diameter and focal length only, how can I find the size of a produced image?
I'm new to astronomy and I'm struggling to understand this concept. For example, A 20-cm diameter telescope with a focal length f = 2 meters produces an image of the moon 1.7 cm in diameter. How large ...
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Telescope on drones to escape light pollution?
Would it be possible to mount a telescope on a high quality drone and fly above the light pollution to get better star shots (if the wind allows it of course)?
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Why do small mirror imperfections matter with modern computers
Modern telescopes go to great lengths to have perfectly shaped parabolic mirrors. My question is, why go to the trouble of having a perfect mirror? Why not take a mirror roughly the right shape, and ...
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How to reduce magnification and increase FOV of a camera attached to a telescope?
I am a beginner in astronomy.
I have a Maksutov telescope (90mm/1250mm). Generally I do observation with a 25mm wide angle eyepiece, but sometimes due to light pollution I can't see many stars.
So I ...
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Where can I find Arecibo's data archive?
Does anyone know where I can find Arecibo's historical data? After much searching, I can find neither hide nor hair of it. It doesn't help that the search results are completely dominated by the news ...
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