Questions tagged [telescope]
Questions related to the physical instruments for astronomical observations.
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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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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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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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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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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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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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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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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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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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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 ...
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Is Sahara desert a good place to build radio/optical telescopes?
At least Atacama Desert of northern Chile is a good place to build telescopes.
VLT and ALMA locate there.
What about Sahara desert?
http://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array
http:...
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Please Guide me to buy my first Telescope [duplicate]
I am a beginner and I've planned to buy a telescope(Newtonian reflector)for viewing planets and deep sky objects. As far as I know the most important factor to get a brighter view is that the ...
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Which type of telescope should I make?
I am not very much interested in observational physics but I just like to look at the night sky. It gives me a lot of inspiration. So, i was thinking about making a telescope for basic observations. I ...
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First night on a telescope questions
So I recently got into astronomy and I am using my fathers old Meade EQ1-B reflector telescope. This is my first night using it and I have come across a few questions. To begin, the telescope was left ...
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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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What is the bluest narrow band filter mounted on ground based telescopes?
If we want to check a QSO's lyman alpha narrow band image, could a ground based telescope do that?
I mean under the circumstance that its lyman alpha shifts to 3300A.
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What is meant by Electronic Beam Steering and how is it achieved?
I recently came across an article about the Murchison Wide Field Array which said directivity is achieved by Electronic Beam Steering and not by Mechanical methods. It would be helpful if someone can ...
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Build a high quality telescope from scratch [closed]
I am interested in building a high quality portable telescope from scratch in an attempt to better understand how telescopes work. What kind of materials do I need? How would I go about putting the ...
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need data-point: actual counts per second with APD (avalanche photodiode) detector
I'm designing a sensor system to perform specialized [astronomy and space-sciences] experiments, and need a "reality check" to support or adjust my theoretical calculations.
What I need is the "...
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Why can't I see Mars clearly?
I just bought my first telescope - a Celestron CDC 1100. It came with a 40mm lens so with a primary focal length of 2800mm the power should be 70x.
My problem is that I've looked at Sirius and Mars ...
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Do telescopes harm while observing sun through them?
I don't know whether we can observe a sun through a telescope. But if we can then will it harm our eyes and if such telescopes exists what is their configuration?
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What's a good step up from 7x50 binoculars?
I own a Nikon OceanPro 7x50 pair of binoculars, but I find that when I look at the moon, I would like more magnification.
My requirements are:
costs less than $400
weighs less than 10kg
the length ...
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Is there an oxide layer on aluminum reflectors for telescopes?
I was watching a Nottingham Science video linked here (periodic videos) and they mention modern reflectors are made of aluminum.
I can understand why mirrors are preferred over lenses, but what ...
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Pictures of large galaxies
The Andromeda Galaxy is tens of thousands of light years in diameter. That suggests that the most distant stars in the Andromeda galaxy is up to tens of thousands of years "behind" in their orbit ...
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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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Telescope buying guide for a beginner in India
I am located in the southern part of India and am looking forward to buy a telescope to gaze up to look ay farther planets, moons in our solar system and take pictures. How should I go about getting a ...
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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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How to build a powerful home made telescope [closed]
Simple, I fell in love with the sky when my parents were constructing our new house I was a kid then and one day I ventured out on the terrace, to my amazement it was a full moon, ever since I've felt ...
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How does a Bahtinov mask work?
For focusing the image of a telescope, one can use a Bahtinov mask. How does this mask work, and how did Mr Bahtinov get the idea to cut such a peculiar shape? Is it possible for me to design my own ...
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Colossus telescope, trying to outsmart aliens?
I was listening to Jeff Kuhn's talk
on SETI's Colossus telescope project.
Background:
He explains his theory that a civilization living somewhere the galaxy would want to hide, and thus would ...
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Planned telescope to detect alien waste-heat
I remember watching a talk by someone who designed a telescope to view a single star at a time.
The purpose of the telescope was to detect waste-heat which would presumably be emitted by any ...
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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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Most important feature of a telescope
I was taking an astronomy test, the following question came up:
The most important function of the astronomical telescope is:
Resolving power
Light gathering power
magnifying power
...
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Are Barlow lenses stackable for bright objects?
I'm back to the refractor that I own, and I want to maximize the zoom capacity. I realized today that I own more than one barlow lens, and I was wondering if I could stack them together for looking at ...
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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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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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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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Periodic error correction in automatic telescopes
I am starting a study on automatic telescopes and the correction of their periodic error.
I found two ways of correcting it : with a CCD camera and manually by recording the error. I was wondering if ...
user30394
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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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Why does squinting make hard-to-see objects clearer?
So I, like most other astronomy enthusiasts, have, at some point, not been able to see something clearly, such as a star, and have had to squint to be able to see it better. When this happens, the ...
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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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