Questions tagged [telescope]
Questions related to the physical instruments for astronomical observations.
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How powerful a telescope would allow me to view the astronauts aboard ISS do a space-walk?
This arose from a comment posted against a question elsewhere on the stackexchange
How powerful a telescope/binoculars would allow me to view the astronauts aboard the ISS do a space-walk? Aperture? ...
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Why are we building larger land-based telescopes instead of launching larger ones into space?
This question is a follow-up to Do bigger telescopes equal better results?
How much bigger does a ground-based mirror have to be to match what a space-based one can do? I guess I'm asking primarily ...
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What will succeed the Arecibo Observatory?
Just a few minutes ago, I got a notification from Space.com stating that the Arecibo Observatory will be, sadly, decommissioned due to extensive damage to its structure. So, with the loss of one of ...
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Why did it take so long to invent telescopes given glass was used 4000 years ago in Mesopotamia?
Is a telescope difficult to make? Does glass have to be polished and shaped very precisely? Or is a device using two or more lenses to magnify things just not obvious?
user50918
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Is it possible to mount a telescope on a plane? Is it beneficial?
I was wondering if any planes had mounted telescopes with the intent to observe the stars. I understand that the atmosphere itself can warp and hinder incoming light and even completely obscure views ...
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How much magnification is needed to see the planets of solar system?
I have a 3inch Newtonian reflector telescope with 300 mm focal length. I can use highest magnification of 75x using a 4mm eyepiece. But in 75x I can't see the details of Jupiter what was expected. ...
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What would happen if someone had a telescope and watched Betelgeuse when it goes supernova?
Would that person go blind?
Neutrino detectors and the abundance of Neutrinos would detect the upcoming visible show about 3 hours before any visible signs, so there would be time to point certain ...
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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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Was Galileo expecting to see so many stars?
Beginner amateur here. I see mentioned many times that Galileo was surprised to see the moons of Jupiter and all that their existence proved, i.e. the Earth not necessarily being the center of ...
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Shouldn't this cause a fire?
This website shows a telescope projecting the sun onto a blackboard: https://astronomyconnect.com/forums/articles/2-three-ways-to-safely-observe-the-sun.21/
Why isn't the board catching fire? You ...
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Is it possible to do planet observation during the day?
Keep in mind I'm just a newbie. So.... I have a new Newtonian telescope. It has 150mm opening and 1400mm Focal Distance on top of an equatorial mount. I have 25 and 10 mm eyepieces... and a 2x Barlow. ...
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What detail can Hubble see on Mars?
I'm researching a scene for a sci-fi novel in which the near-future protagonists observe earth through a station-mounted telescope in Mars orbit. My goal is to understand how much detail they ...
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Why is Starlink polluting the night sky a big concern if we have space telescopes?
There's a lot of concern in the Astronomy community over the deployment of Starlink satellites. For a good discussion, see the related question How will Starlink affect observational astronomy?
But ...
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Please check my Mars photo
Hi built my own newtonian telescope for the first time. Up until that point I had never used a telescope.
Can you please look at the photos attached and tell me if this is what Mars should look like ...
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Why are wavelengths shorter than visible light neglected by new telescopes?
The diagram below, which I stole from this post by @HDE226868, shows that angular resolution as a function of wavelength suddenly drops by three orders of magnitudes from visible to UV-light. The ...
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How can telescopes see anything at all?
I'm impressed that we have any telescope imagery at all. Take the images we have from the "Pillars of Creation".
The Pillars of Creation is in the Eagle Nebula, some 7,000 light-years away ...
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How can we focus radio telescopes on a star when the earth is spinning?
Reading about the Star KIC 8462852, it has been said that the SETI project turned its radio telescopes towards the star to search for extra terrestrial radio signals as the star had strange ...
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Should I focus more on Aperture or Focal Length for a telescope?
Let's assume there are three types of telescopes with the following specifications:
...
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Could we detect the light of cities at night in other solar systems?
Would it be possible to see electric lights on distant planets using current telescopes?
user48394
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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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Why are almost all modern telescopes reflectors?
I've noticed lately that reflector telescopes are used much more than refractors. The majority of telescopes I see in telescope shops or featured by people online are reflectors. Even the Hubble and ...
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Determine the moons of Jupiter through a telescope
I was doing my own "space exploration" last night with a telescope. Being a space noob I can't visually determine stars or planets (I know the moon, though), but I focused on one particularly bright ...
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Is there any telescope on Earth that can see the lunar rovers on the Moon?
If I have the right numbers, it seems to me that even the Hubble telescope might barely be able to make out a carcass of a blue whale on the surface of the Moon, which puts objects as small as the ...
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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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Why different specifications for telescopes and binoculars?
Sorry for the noob question but I don't seem to be able to find the answer on the internet.
I've been looking through some telescopes and binoculars and noticed that shops typically give different ...
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How do satellites impede current telescopes?
As we send up more and more satellites, it stands to reason that our view of the universe becomes more and more obscured. I would certainly expect for example that a large telescope such as the LSST ...
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A good telescope for the viewing of Nebulae, Stars and Planets
So, I am a 15 year old interested in astronomy. My father used to have a reflector telescope, but was never so serious about it that he could recommend me a good telescope. I am looking to buy a ...
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Space telescope located in outer solar system
I want to pose a question from someone who's astronomy knowledge would fit neatly onto a single piece of paper so please bear this in mind with any comments or answers. I am interested and want to ...
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What telescope is Polish astronomer Kazimierz Kordylewski holding in this April 1964 photo at the Jagiellonian University Observatory in Krakow?
The following questions touch on Kordylewski clouds
Can dark matter accumulate at Lagrange points?
Are dust-dust collisions necessary to explain Kordylewski clouds at Earth-Moon L4/5? Aren't the ...
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How Does a Refractor Telescope Work?
As I understand it, the difference between a reflector and a refractor is that a reflector uses mirrors on the back to reflect the light to the secondary mirror then the secondary mirror reflects the ...
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Why are telescope mirrors made of glass?
Optical telescope mirrors are typically made from endlessly polished glass surfaces that have been aluminised to provide a very smooth surface of reflective aluminium.
But why the need for glass at ...
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What was the largest telescope ever fitted with an eyepiece
Serious modern telescopes use CCDs to capture the results. This makes it convenient to process or display the results halfway around the world. However, there is something visceral about looking ...
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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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Using the Sun as a Gravitational Lens
Can the Sun be used as a gravitational lens to achieve better telescopic viewing? Can this effect be practically used to view celestial objects?
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Is it possible to figure out your location in the Milky Way if you are suddenly wormholed to a random, distant location in the galaxy?
If you were flying along in your spacecraft somewhere in our solar system and then a large, stable wormhole suddenly opened and you flew into it and were whisked away to some distant location in the ...
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What are the next planned space telescopes?
We've had hubble for two decades. Its become the most famous space telescope, and lately Kepler seems to be running for the second place. Are there any more powerful, better telescopes planned for ...
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After Oumuamua passage, has an "urgency" telescope time request procedure been set up?
During the rapid passing of ʻOumuamua through our solar system, it was difficult to get instant telescope time. Usually, formal requests and a review process are necessary before telescope time is ...
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What limits the usable focal length of telescopes currently?
What barriers - of technology, physics and possibly economy (things that would be possible technologically but are simply too expensive) sets the upper bound on quality of telescopes for observation ...
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Are there plans to detect life on Earth from the outer solar system?
This has been kicking around in my head for a while. We've been detecting planets for decades by observing regular dips in starlight from many light years away as a planet transits its host star. I've ...
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Why are telescopes positioned in Lagrange points?
In this Wikipedia article about the list of space telescopes to be launched (which I assume is exhaustive), of the 11 telescopes yet to be launched, 6 will be positioned at the Sun-Earth L2 Lagrange ...
user30617
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Recording Spectral Lines at Home
I was wondering if it would be possible to record the emission/absorption spectra of stars without expensive spectroscopy equipment. Would it be possible to somehow utilize diffraction grating? I own ...
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What visual artifacts are expected from the JWST?
What visual artifacts should we expect from the images that will be released from the James Webb Space Telescope? Specifically, do we expect 3-pronged diffraction spikes (any preview how they would ...
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How does a telescope measure parallax angle?
I know how stars' distances are measured by using parallax, but I want to know how the actual telescope measures the parallax angle. Any helpful links/ explanations are needed.
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What is the highest resolution image of the moon taken from Earth's surface?
According to this article:
https://www.theguardian.com/science/2018/jul/26/star-spotted-speeding-near-milky-way-black-hole-for-first-time
the Very Large Telescope is "powerful enough to see a tennis ...
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Does the Reflection Method for Looking at the Sun Work For Refractors?
I own a newtonian reflector and occasionally use it (using the reflection method with paper) for looking at the sun. I happen to also own a refractor, but I'm not exactly sure if the reflection method ...
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Method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? [closed]
What is the method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? (Not from occlusion but actually visible on its own.) Further, ...
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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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Why can't we build a huge stationary optical telescope inside a depression similar to the FAST radio telescope?
So first we'll have to find a natural depression or we should create one. I understand you can only see a single portion of the sky since it can't be moved, so my money is on creating an artificial ...
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Why are segmented mirrors lighter than monolithic mirrors?
Everywhere I look, it is recited as a quasi-mantra that "segmented mirrors are much lighter than monolithic mirrors", and I can't manage to find an explanation anywhere no matter how hard I ...
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Could we parallax measure stars just based on the Earth's size?
Imagine two major surface observatories, perhaps the "northermost" and "southernmost" such (ideally on a similar longitude).
For nearby stars, could they each take a photo at the same time, and ...
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