Questions related to the physical instruments for astronomical observations.

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If we built one hundred 3m telescopes and point them to a single star what would be the final resolution?

We'll mount all of them in a same location and connect them to each other (like VLT) so they will combined all the results and will produce some staggering images however my question is, would they be ...
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16 views

Can ground based telescopes use a starshade in space?

1) Could a starshade in orbit be used by ground based telescopes? If so, what kind of orbit should it have? 2) Could the same starshade be used by two different space telescopes, or does the ...
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1answer
32 views

Is it possible to use the stars to determine the passage of time?

I'm writing a science fiction short story which involves a group of people being in suspended animation for a very long period of time, on the order of thousands of years. My question is, would an ...
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1answer
52 views

What kind of telescope do I need to see most of the Jupiter's moons?

I have a simple Newtonian reflector telescope. Using it, I am able to see the Galilean moons of Jupiter. However, Jupiter has much more moons than that (Wikipedia says 67 have been discovered this ...
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12 views

How can we see the Milky Way Galaxy when we are already in it? [duplicate]

How can we see the Milky Way Galaxy when we are already in it? I have seen lots of pictures of Milky way galaxy. Consider yourself being in a room, how can you see it from out when you are already ...
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1answer
60 views

How can a galaxy in-between our view and the galaxy behind it have a 'lensing effect'?

In this article, the author writes: This galaxy is so distant that it would have been invisible without the gravitational lensing effects of a large galaxy cluster called Abell 1689, located ...
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2answers
61 views

Nebula and galaxies using 70mm scope

Telescope: Orion 09843 SpaceProbe 3,3 inch aperture(76mm), 700mm focal length, eyepieces - 25mm and 10mm focal lengths. Please tell me whether it is possible to see nebula and galaxies.
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53 views

How do I soundproof a Meade ETX-90 telescope?

I'd like to start using my Meade ETX-90 this summer in my backyard, but I'm worried that my neighbors will start complaining due to high noise this telescope makes when operating. How do I soundproof ...
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2answers
61 views

Enhanced Star-Gazing with Special Glasses

I watched a video yesterday on how telescopes not only magnify images but also increase the amount of light entering into your eye, allowing you to see things not normally visible with naked eye. ...
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1answer
44 views

Telescope size to detect Ceres (Newtonian)

What is the minimum size telescope required to enable clear visual detection of Ceres?
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1answer
57 views

What is the typical resolving power of the largest optical telescopes?

I'd like to estimate the typical resolving power of the largest optical telescopes. I've calculated the theoretical resolving power of the VLA for 21 cm light, $$R=\frac{\lambda}{B}=\frac{2.1 \times ...
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1answer
34 views

How long does it typically take to make a telescope yourself for the first time? [closed]

How difficult is it to make a telescope oneself? How much time would it take for a first-timer? What are the typical pitfalls?
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20 views

What are the up- and downsides of spherical and parabolic mirrors in telescopes?

What are the up- and downsides of spherical and parabolic mirrors in telescopes? I was able to find small bits of information from the web but not a good comparison. Assume the telescope is a ...
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1answer
92 views

Difficulties in finding Jupiter

I am new to astronomy. Jupiter is now visible to the naked eye but I have difficulties in locating it with my (new Newtonian reflector) telescope. The lowest magnification I have is 36X, which I guess ...
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1answer
56 views

What kinds of technologies are required to directly image exoplanets

I have read that immensley powerful telescopes such as the European Extremley Large Telescope will be able to directly image the atmospheres of exoplanets, and even determine their rotation rates. I ...
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1answer
78 views

Hubble HST scheduling algorithm

NASA developed SPIKE: Intelligent Scheduling of Hubble Space Telescope Observations (HST) and this. My question is simple, is there a programming library, preferably in python or C#, to implement the ...
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2answers
198 views

How much magnification is needed to see 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 details of Jupiter what was expected. Instead ...
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0answers
52 views

Is there a cosmic, rather than technological, upper limit to what a telescope can resolve?

Space radio interferometers could have a baseline of millions of kilometers, but is there a point where a larger baseline doesn't improve the resolution anymore because the photons observed are ...
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1answer
43 views

PowerSeeker 114Q

I just purchased a powerseeker 114q by Celestron. This is my very first telescope. I believe I assembled it correctly however I can't see anything out of it. Well I can see a small corner of an image. ...
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1answer
34 views

When is Gamma Draconis closest to the zenith in London on April 4th

I am reading Roobert Hooke's paper An attempt to prove the motion of the earth from observations (1674, faksimile). Hooke writes The principal dayes of doing which will be about the 4 of April, ...
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3answers
780 views

Is it safe to view moon at daytime through telescope

I have a little 76mm Newtonian Reflector. I want to see the moon at daytime. Is it safe to look at sky at daytime when sun is shinning or there is any risk of sun.
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3answers
59 views

the initial astrometry calibration for a telescope

Generally a telescope can memorize how to point to a target with a particular RA&Dec. There is no need to calibrate every day. How can it happen? How to let the telescope(non-amateur) know the ...
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2answers
62 views

How do or could radio telescopes contribute to exoplanet studies?

Current and upcoming telescopes which find exoplanets and take spectra of their atmospheres seem to be optical or infrared. What about radio telescopes applied to exoplanets? They are larger and more ...
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1answer
125 views

Basic DIY Telescope

I am looking for a design of a cheap and easy telescope to build with my 9yo daughter with the only basic requirement being that I'd love to be able to see detail on the moon. Looking around, there ...
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1answer
64 views

Smallest body that can be observed from Earth?

What is the minimum size of an object that can be observed from Earth with our most powerful telescope? I understand that the answer depends on how far the object is from Earth. For the sake of ...
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1answer
64 views

Method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle?

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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1answer
50 views

Is it possible to steer the sight of a Liquid Mirror Telescope using a plain mirror scheme? If yes, why hasn't it been done?

I have read about Liquid Mirror Telescopes in a number of places, and according to these sources, a major disadvantage of these telescopes is that they can only "see" straight up. In a nutshell, the ...
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2answers
136 views

What are the nearest galaxies I can observe?

What are the nearest galaxies I can observe using my Telescope? Does it require to be out of the city lights?
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2answers
74 views

What range of exit pupils work for observing the full moon?

I'm observing the full moon, from a major city, with heavy light pollution and dust. The objective size is fixed, for this comparison, something between 4 and 6 inches. The question is about the ...
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2answers
126 views

What should I look for in an astronomy tripod?

I have a Celstron SkyMaster 20x80 binoculars, and a tripod — Vanguard 263AT with a SBH-100 head. The binoculars weighs 2.2kg, while the head is rated to a loading capacity of 10kg, and the legs to a ...
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1answer
78 views

Is there a theoretical limit on telescope's resolution?

Is there a theoretical limit on what we can see with a telescope of fixed size based on Earth's orbit or the Moon, that is in Earth's region of Solar system outside the Earth's atmosphere? Why not ...
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1answer
32 views

Tools for creating a multiwavelength view of the sky

Not sure that this is the correct place to ask this question, but here goes. I am trying to find tools to accumulate image data (preferably in FITS format) on a given (RA, Dec)-coordinate of sky. ...
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2answers
187 views

Selecting a Telescope for Viewing Planets

I hope to observe planets like Jupiter and Saturn, and moons. I am a novice when it comes to telescopes and I know images in magazines are not taken with at least 12-inch telescope in a middle of ...
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2answers
48 views

How do I find the RA of sunset and sunrise in a specific location?

I want to make some observations with a telescope in Hawaii on Mauna Kea but I am living somewhere else (not Hawaii) and I want to plan a night's viewing on the Hawaiian telescope. How do I find the ...
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1answer
114 views

What can a lunar-based telescope do?

What can a lunar-based telescope do? If the band is ultraviolet and it can do high time sampling exposure, maybe it can be used to get distance for a star with stable pulses. However, the star should ...
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1answer
71 views

Starting out in practical astronomy [closed]

I want to start observing the night sky, what advice would you give to get started?
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2answers
67 views

Telescope on polluted environment

this one bothering me,to buy a telescope. I live in a city,unfortunately with dust and polluted air, is there any affect in viewing a nice capture of our galaxy? Or i need to buy a special telescope?
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1answer
48 views

How to polar align an equatorial mounted telescope when you are close to the equator?

I recently moved to southern Mexico (16 degrees N) and I wonder what would be the best way to align my EQ telescope when the polar star is not visible?
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1answer
29 views

Collimator for Dobsonian, same as Newtonian?

I have been looking on line for Collimator for my Meade Dobsonian. The only Collimators I can find are made for Newtonian Lenses. It's a 8" mirror with a 1.25" lens. Will this work for my telescope?
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2answers
44 views

Distance between each dish in an array telescope configuration

In an array telescope configuration, like VLA and ATA, what dictates the distance between each dish?
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1answer
67 views

How do telescopes “zoom” and change angle of view?

Images from the Hubble Space Telescope have widely different angles of view. Is this only the result of composing multiple images, or can the telescope itself change its "zooming" optically, ...
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1answer
20 views

How to compare a Catadioptrics light asorbtion with a reflector?

I used to have a 6" Dobsonian reflector, and the next telescope I buy, I want it to have the equivlant of about a 11/12" dobsonian reflector. I'm looking at this Nexstar VX 9.25 , it says 235mm ...
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1answer
41 views

Alt-Az or Polar?

I have a Meade wedge that I am to install on one of their LX200 telescopes. Will I be able to align in alt-az afterwards? Is polar easier or harder to make an alignment? Any other tips welcome. Thanks ...
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0answers
59 views

what will be the exact position of the Thirty Meter Telescope [closed]

TMT will be put at Mauna Kea in Hawaii. It should be near Keck and Gemini. However it seems there is no place left at that site. What is the exact position?
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2answers
88 views

Schmidt-Cassegrain telescope

What is a Schmidt-Cassegrain (SC) telescope? We have Newtonian telescopes and also Galilean ones. How is SC telescope different from other optical telescopes? What is its construction detail and ...
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1answer
82 views

CCD in telescopes: Observation and Astro-photography

This is a Celestron CPC 800 XLT telescope. It doesn't seem to have charge-coupled device (CCD) attached. Can a CCD be attached separately to this 8" Schmidt-Cassegrain telescope even if it didn't come ...
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1answer
111 views

Any cheap (less than 100 euro) telescope for observing Jupiter? [closed]

The moon is not challenging. I would like to observe the big planets and their rings.
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4answers
181 views

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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1answer
121 views

Calculate telescope orientation based on RA, DEC and Lat/Long

I'm parsing FITS files for a project based on data from a telescope. These files include 'DEC', 'RA' and lat long values. I understand roughly the concept of celestial coordinates and I assume that ...
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1answer
117 views

What determines which frequency range a radio telescope has?

My simple understanding is that a parabolic dish focuses radio waves to a receiver. It is obvious that any parabola focuses visible light and heat, so I assume that it focuses all radio wavelengths ...