Questions tagged [telescope]
Questions related to the physical instruments for astronomical observations.
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Is it possible to observe strong gravitational lensing with amateur telescopes?
Strong gravitational lens systems like the Cosmic Horseshoe have been imaged by scientific space telescopes, but have any amateur astronomers accomplished this?
Or are amateur/small ground based ...
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How are non-visible electromagnetic waves detected that originate from space?
How are non-visible electromagnetic waves from space detected and interpreted by the receiver? Is it in the same manner, as say radio waves produced on Earth, where the EM wave interacts with the ...
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Is Cosmic Ray Astronomy a thing?
Historically astronomy has been the regime of visible light, looking at distant objects in the visible spectrum and later taking photographs in the visible spectrum.
In the past century radio ...
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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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Hypothetically, could a civilization in a solar system near a supermassive blackhole use the blackhole as a huge gravity lens telescope?
I have heard of various proposals that use the massive gravity of stars to sort of focus light at and observe with a suitable telescope placed at such a distance, and I am assuming here that bigger ...
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Plotting Equatorial coordinates to X,Y plane (simulating telescope/camera view)
I would like to simulate a telescope camera view, projecting (RA, Dec) coordinate sets to a 2D plane. So effectively the need is to convert Equatorial coordinates to (x, y) coordinates, when we can ...
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Convert apparent magnitude in a filter to a luminosity
I have data in Johnson B & V filters and I would like to convert the observed magnitudes, m$_x$, into luminosities, L$_x$, over a passband where I already know the distance, d, to the object. x is ...
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What to do in case of concentric circles that are not aligned with the cross after collimation (Picture inside)?
I have been collimating my newly bought first Newtonian telescope for a few days now, but I can't get the center of the circles to align with the intersection point of the spider's reflection. I have ...
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How did I flip some mirrors around in the dark at 3 AM and change the focal length of a 24 inch Boller and Chivens?
Current answer(s) to How do telescopes "zoom" and change angle of view? are "they don't", but traditional large genera-purpose observatory telescopes do sometimes (often?) have ...
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Are X-ray telescopes with glancing angle surfaces basically "funny-looking" Cassegrain telescopes mathematically?
In this answer I included the image below of a reflective X-ray telescope. It is made from two elements; the first is concentric shells of glancing (high incidence) angle paraboloidal surfaces, and ...
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Size of crosshair
TL;DR: Does anybody know the width of a single crosshair as a fraction of the full field of view on a Skywatcher 1.25 inch 12.5mm illuminated reticle?
Explanation (in case there's a different question ...
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What happens to the Fourier Transform of the Measured Spectrum?
What happens when you double the width of the entrance slit of a spectrograph, in turn letting in twice as much light, would there be an improvement in the Fourier transform of the measured spectral ...
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Limiting magnitudes for different telescopes
I live in an extremely light polluted place. On a new moon night, magnitude 3.5 stars are at the limit of naked eye visiblity on clear nights, and the Orion nebula is visible as a smudge through my ...
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Spectrograph Arrangement, Noise, and Fourier Domain [closed]
If the transform of a line profile extends out to the Nyquist frequency such that we cannot see the noise level, what could we change in our spectrograph arrangement that would allow us to see the ...
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What is the gain of a telescope?
What is the gain of a telescope? How would I go about calculating the gain from a flatfield image?
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Please Help Me With Choosing my 1st Telescope
I'm going to buy my 1st telescope. With the budget, I've shortlisted some. Tried with the YT videos, reviews and guide. Few things still bugging me. Hope somebody can give me any advice on this. There ...
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Telescope showing high chromatic aberration
Hi i have made a telescope with 1100 mm focal length objective lense and 21mm plano convex as eyepiece. Both these lenses are not achromatic. But when is looked through it , the images were completely ...
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Can you attach an old Vixen model to a celestron tripod?
I would like to know if I can put an old Vixen VMC model (15 years old) onto a celestron 4se tripod. I am aware that some adaptations must be made, but I want to know if it's even possible or if it ...
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Diameter of the moon from the diameter seen in the telescope
I'm reading a chapter on convex lenses and it has this diagram:
The chapter explains that triangles ABC and ADE are similar. Thus, ratio of CB to DE is equal to the ratio of BA to AD.
Does this mean ...
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Why telescope mirror glass shipped as randomly broken chunks of a constant size in cardboard boxes?
The video MIRROR LAB: Preparing for Casting GMT's Mirror 6 shows the unpacking several hundred boxes full of broken glass from OHARA, packed in styrofoam.
The glass chunks are a fairly uniform size of ...
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Tradeoffs "upgrading" from a 60/900 refractor to a 150/1200 Dobsonian?
My current/previous telescope is a Skywatcher 60/900 refractor on an equatorial mount. I am now looking at a SkyWatcher 150/1200 "Classic" Dobsonian reflector.
How can I compare the two in ...
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Convert Object Intensity to Pixel Intensity
If I have an object of some size and spectral radiance, and it's some distance R from a camera, how would I calculate its digital count value in an image? I'm sure there's an equation out there, but I ...
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Benefits to adding a 32mm Pössl to my Celestron AstroMaster 130EQ's eyepieces?
I am getting a Celestron AstroMaster 130EQ soon. I have heard that its eyepieces aren't the best, so I am considering a 32mm Pössl.
For such a choice, what would be the arguments for and against? How ...
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Maritime telescopes: Stabilisation requirements for optical vs. radio telescopes?
SOFIA stands for Stratospheric Observatory for Infrared Astronomy. She says:
My telescope stays stable with a spherical bearing, shock absorbers, and gyroscopes.
I suppose a similar system would ...
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Celestron uncommon DC long barrel connector
I have tried to connect a 12v DC adaptor and also a battery pack to my telescope unsuccessfully. Sadly it seems Celestron DC jack needs to be around 2mm longer than common 5525 DC ports.
I was ...
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What are recent discoveries with Earth-based radar telescopes?
The Wikipedia article on radar astronomy lists a few important discoveries using radar technology in general, i.e. also using space-crafts:
The following is a list of planetary bodies that have been ...
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Can I see Jupiter, Saturn, Mars and Venus with the Spectra Optics Telescope 600x50? [duplicate]
Is it possible to see Jupiter, Saturn, Mars and Venus with the Spectra Optics Telescope 600x50? And even the moon?
This is the description of the telescope:
User-friendly and easy to install with ...
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Can I see Jupiter, Mars and Saturn through the National Geographic 76/350 Dobsonian Telescope?
Is it possible to see Mars, Jupiter and Saturn through the National Geographic 76/350 Dobsonian Telescope? It's the most affordable telescope I can get at the moment. Also, what about the moon? Will ...
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Is sky-glow affected by height?
I'm an architecture student and my graduation project will consist of building a research center for outer space, my question is whether or not height would affect sky-glow or not ? Thanks in advance, ...
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How to connect my phone to a motorized telescope via a cable?
Some motorized telescopes (e.g. Celestron NexStar Series) have no WiFi by default. Can I connect my phone to them to be used as a hand control via a cable? The telescopes have AUX port and phones USB ...
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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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Can the "haze" of a mirror telescope be quantified?
When reading Why was StDr56 discovered only now? and its answers and comments, I realized that refractor telescopes, and in particular the Dragonfly Telephoto Array are a great tool to find nebula and ...
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What eyepiece to use for moon?
I'm using a 95mm f/8.4 telescope. What's the best eyepiece that I can buy for a very close look at the moon or even planets? I'm a beginner in this field so please help me.
Thank you.
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Can we visually perceive exoplanet transits with amateur telescopes?
Is it possible for an amateur astronomer to visually perceive an exoplanet transit by the change of brightness of the star via observations spaced over time, or is the variation of the brightness too ...
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Fresnel lenses for a makeshift Galilei telescope?
For a kindergarden (pirate) party, friends of me want to build together with the 4 year old kids a functional pirate's telescope for each of the kids. On the web I found full constuction sets, e.g. ...
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How do we differentiate between a star or planet and noise introduced due to equipment?
I understand that differentiating between celestial bodies and noise due to equipment is a fundamental problem in astronomy. I also understand that we solve this problem by looking at something called ...
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Using a refractor telescope 5" aperture, 900mm focal length for terrestrial viewing
Can I use a refractor telescope 5" aperture, 900mm focal length on an equatorial mount for terrestrial viewing.
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Understanding energy loss in a telescope aperture due to atmospheric dispersion
I'm trying to understand energy losses due to atmospheric dispersion, given the plot below from the Keck telescope.
For a typical seeing I'm told that there's 80% encircled energy in 1". The ...
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Telescope lens problem when cold
We are having a problem with our scopes on cold nights. (-10F is about average here.) One poorly aimed breath means that the eyepiece lens fogs. We have to remove the lens and keep it under our arms ...
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Upgrade tripod on a cheap telescope
I got a cheap refractor as a present - my intro to astronomy. I think it’s not great, but I’m having plenty of fun looking at the moon and planets, and who knows, maybe some other objects soon.
The ...
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Is it possible to use Photolithography for telescope image sensor?
The current largest digital CCD camera is the Vera C. Rubin Observatory, which has a whopping 3.2 gigapixels with a pixel size of 10 micrometers. In contrast, Agfa 10E56 holographic film has a ...
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What is the size of the image sensor in the largest optical telescopes?
What image sensors (imaging electronics) are used in telescopes? Like CCD, is that the best option?
What is the typical physical size and resolution of the photo-sensitive surface of the currently ...
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How difficult is it for an amateur to discover a new exoplanet or astronomical object?
I recently read about precovery, where plates or images of an object predating its discovery are used to precisely determine its orbit. It occurred to me that it might be possible that some objects ...
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Limits of space telescope?
Watching this video describing the "next generation" space telescope, it seems like the biggest mirror will be ~6 meters in diameter.
Theoretically, if a telescope was built in space instead ...
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Is there a common metric to measure telescope power?
It is rather hard for me to compare telescopes due to the various numbers used.
600mm focal length and a 50mm diameter and eyepiece is a 12mm.
VS.
Focal length of 500 mm and the objective diameter is ...
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Question about telescope eyepieces
I have a Celestron 60LCM refractor telescope. It has a 60mm aperture and a 700mm focal length. It came with two eyepieces. One is 25mm and the other is 9mm. They are marked only with their focal ...
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How to estimate my eyepiece FOV?
As a follow-on to my question about seeing Jupiter and Saturn at the same time in my scope, I'd like to ask how I might determine the Field of View (FOV) of my eyepieces. More specifically, I'd like ...
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Will I be able to see both Jupiter and Saturn at the same time in my Astromaster 114?
I have a Celestron Astromaster 114 Newtonian reflector telescope. The specs:
aperture: 114mm
focal length: 1000mm
focal ratio: f/8.77
I also have a t-ring so I can connect a Nikon camera to it.
Will ...
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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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Sky-Watcher Dobsonian 16 Inch Synscan Go-To [closed]
What is the best way to buy Dobsonian telescope 16‘? Where can I buy it new or used? What I will need to have in advance? Which negative sides it has? Please, share any information you have about this ...
