Questions about the observation of celestrial objects by non-professional astronomers.

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1answer
122 views

What is the first recorded reference to the Moon being a satellite of the Earth?

I saw a list recently of the moons of the various planets and the discoverer(s) and date of discovery. Earth's Moon was listed as Unknown. I know you don't 'discover' a huge disc in the sky. But ...
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1answer
38 views

Pinhole Projector: Can I use a specific solar optical eye piece to focus the Transit of Mercury?

The title pretty much explains this one. Can I use a specific solar optical eye piece, or other optical device, in conjunction with the pinhole projector method to focus the Transit of Mercury? ...
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0answers
25 views

How to orientate a telescope using an accelerometer and magnetometer?

For a project with my astronomy professor, we are hooking up an array of 4 smaller telescopes to observe objects in space together. To do this, we wanted to put an accelerometer and magnetometer on ...
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1answer
70 views

Does weight influence Earth's spin? [closed]

If put enough weight on a particular point on Earth's surface disturbing the balance between hemispheres, is it possible that the Earth's spin could change like an unbalanced spinning top?
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2answers
112 views

Was that actually a shooting star during the supermoon eclipse on September 27th 2015?

During the super-moon total lunar eclipse on September 27th a meteor-like streak passed very close within view of the event. It appeared to happen at the very middle, the maximum eclipse. ...
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1answer
78 views

When was the nearest star discovered? [closed]

When historically did we realize that the Sun is a star, like all the others? An answer was posted, then the question was put on hold. I would like to answer: If indeed someone asserted that the Sun ...
3
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1answer
62 views

Moving from computerised to normal amateur telescope?

A few years ago I purchased a Celestron Nexstar 130 SLT computerised telescope thinking that it would be a perfect to get me into astronomy. The issue is the computer doesn't work at all and manually ...
5
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1answer
165 views

Watching the Mercury transit with improvised devices

I have learned that it is not possible to watch the upcoming Mercury transit with the plain eye (using special filter glasses). Is it possible to watch the transit with improvised devices (like a ...
3
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1answer
63 views

How big will Apophis appear?

How big will Apophis appear in the sky at its closest point of approach in 2029? Will it compare to the moon? How long will it linger as it passes?
3
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1answer
172 views

Pinhole projector for the Transit of Mercury

Very quick and simple one today. What would be the best/optimal pinhole size for a pinhole projector to observe the transit of Mercury on May 9th? I want to get the optimum between resolution and ...
0
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1answer
26 views

A good place to start? [duplicate]

I am a high school student (going into 11th grade next year), who will be taking an introduction to astronomy and astrophysics as part of my core curriculum. As such, I would like to get a head start ...
6
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1answer
173 views

Can you see city lights on the Moon from Earth?

This is the opposite of another question. That question is about whether you could see cities on Earth if you were standing on the Moon. Let's there are cities on the Moon and you're standing on the ...
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3answers
154 views

What will be Supernova SN 2014J's peak brightness?

What is the expected maximum apparent magnitude of supernova SN 2014J? When will it attain peak brightness?
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2answers
155 views

What is the fifth moon-like object I saw around jupiter through my telescope?

Tonight while observing Jupiter I was able to see a five (what looked like) moons. I have observed Jupiter often before and only been able to make out the four galilean moons. It's my understanding ...
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1answer
70 views

Jupiter appearing odd through a 6" reflector

Recently I have been trying to get a good look at Jupiter through my 6" Orion reflector, but the image seems to always come out as an oblong white streak. I've tried changing the lenses I'm using, but ...
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2answers
128 views

How can apparent magnitude be negative?

What is the reason for that scale? Is it because otherwise defining an maximum would be too hard(?). Why do objects that are (apparently) brighter get assigned a smaller number (and down to negative)? ...
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0answers
78 views

What was the flash I saw in the night sky?

On Saturday night (April 2nd) in Sydney, Australia, somewhere between 8:30 PM and 9:00 PM my partner and I saw three flashes in the sky. We were looking at Jupiter through a pair of 7x50 binoculars ...
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1answer
84 views

Can you see the stars when it is trickling?

I am writing a book with the following scene in one chapter: It is trickling and my protagonists are outside looking into the night sky, looking to the stars. Reviewing the scene I am wondering: Is ...
26
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3answers
6k views

Did I see another planet?

A couple days ago, I zoomed in with my 30x optical zoom camera, and after some exposure adjustments, a bright star in the night sky turned into this: Are those other planets or other stars? Or is ...
5
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1answer
53 views

Where can I find/visualize planets/stars/moons/etc positions?

What resources are available to find the positions of planets, stars, moons, artifical satellites, asteroids, and other heavenly bodies?
4
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2answers
184 views

What are some night sky objects I could see with my Celestron UpClose 20x50 Porro Binocular?

I bought this binocular because I've read countless times that one should start with a pair of binoculars before diving into telescopes. I've seen details of the moon and I can notice Venus round ...
2
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2answers
71 views

Why aren't planet orbits circular? [duplicate]

Please forgive the simplicity of my question. I have only had basic science courses. Common sense seems to indicate that planetary orbits should be very close to circular, any perturbations having ...
3
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2answers
483 views

Which of Jupiter's moons did I most likely see?

I was gazing through my binoculars at Jupiter last night and noticed 3 (maybe 4) tiny dots in line with it. A first I thought they might have been background stars but quickly realised their colour ...
0
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1answer
29 views

How to calculate B-V colour index value percentage difference

I need to calculate a percentage difference of a B-V colour index between its estimated and actual value. So I tried doing this by difference between values/actual value x 100. However as B-V values ...
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2answers
116 views

Dish antenna as parabolic mirror for OPTICAL telescope?

Can i use a chrome painted dish tv antenna as a parabolic reflector for my Optical telescope ? Given that glass mirrors are quite expensive, i am thinking of using a Dish TV antenna and coating its ...
0
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0answers
16 views

How useful are filters for spotting nebulae?

Recently I've been trying to spot a couple of nebulae, IC59 and IC1318. The skies at the site are modestly dark (4.5 on the Bortle scale), I'm using an 8" scope, and I've slowly scanned around the ...
3
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2answers
124 views

What are the advantages and disadvantages of a 2-inch eyepiece versus a 1.25-inch eyepiece?

I'm considering picking up some new eyepieces for my telescope and am interested in comparing 2-inch and 1.25-inch eyepieces. Are there any disadvantages to 2-inch eyepieces? Are 2-inch eyepieces only ...
0
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1answer
33 views

SDSS. Google Sky and DeCaLs

(1) Please go through following image Possible Super Red Giant? However sdss shows it as galaxy! Am I missing something. (2) Google Sky shows object in latitude and logitude format like this. Is ...
3
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2answers
36 views

What Are Some Good Southern Hemisphere 7x50 Binocular Targets?

I've been interested in astronomy for a while but only recently purchased my first set of binoculars (7x50). I've been learning various constellations as well as spotting some other objects with the ...
6
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2answers
314 views

Can I look at the sky and find the day of the week?

Suppose I wake up from a coma on a desert island in the 19th century (i.e. we already use the Gregorian calendar but have no satellites yet). I have a clear view of the sky and a couple of days to ...
5
votes
1answer
107 views

How were the orbits of planets first mapped out?

I'd like to know how the orbits of planets were first 'mapped out' and to understand the maths behind it. e.g. How do we know what position in space a planet will be at certain time so that spacecraft ...
2
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2answers
12k 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 ...
5
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3answers
283 views

Should this photo of the sun's surface actually be white?

If I'm told correctly (eg. What Color is the Sun?) that the sun is actually white, should the photo on that page actually be white too? Is it just doctored to meet peoples expectations?: Likewise ...
8
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2answers
124 views

How many stars are in the constellation Canis Minor?

I've read Wikipedia and found a list of stars in Canis Minor, and counted the number of stars in the list. I came up with 56 stars, a surprising number. I did some more research and found that Canis ...
4
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1answer
48 views

What is an “arc” spectrum ?

I sometimes hear about astronomers using an arc spectrum to calibrate observations. For example a "He-Ar arc spectrum". What is an "arc" in this context? I assume it's nothing got to do with angles ...
2
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3answers
74 views

Orion Constellation request

This isn't a question so much as a request. I'm looking for an image of the Orion constalletion I could use, but I would like to have a very high resolution HD image, whereby a lot of the deep sky ...
3
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1answer
62 views

Annual path polar chart for a star

I've often come across sun path charts like this (Wikimedia Commons) that show the position of the sun at any point of the year, at any time of day, for a specific location (or a set of locations), on ...
5
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1answer
53 views

Diameter of Astronomical Object Using Magnification

I took a picture of Jupiter through my telescope, using an iPhone. I know the magnification of the telescope lens I used, and can Google to get the magnification of the iPhone lens (the magnification ...
3
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2answers
87 views

What are the stars/constellations a beginner/enthusiast can easily identify?

I was just wondering what are some of the stars, constellations or any other things that one can just identify by looking up at the night sky. For example, when ever i look up, I immediately see ...
5
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3answers
154 views

Visibility of human activity on the moon

In this video the host of Test Tube Plus states that you can go out a buy a laser, point it at the moon, and see the retroreflector left by the astronauts. When you point at the right spot you'll ...
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0answers
70 views

Why some stars appear to move differently when viewing device shakes

I was looking at Arcturus with a pair of binoculars, and noticed that when they vibrate due to my heartbeat, Arcturus seemed to move differently than the other dimmer stars. I started playing with ...
2
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2answers
54 views

Astronomical telescope making

I am thinking about making a telescope. I have a 100cm focal length lens which I can use as objective lens in my telescope. So which is the best focal length I can use as eyepiece in my astronomical ...
2
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0answers
85 views

What would this moving point of light be?

Tonight (10:00 PM EST Middlesex County, Mass.) when looking at the mostly clear sky I observed what I at first believed was a meteor. This point of light was moving east to northeast and that would be ...
2
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0answers
45 views

Illusion of a lunar eclipse [closed]

A little over half a year ago, I think it was mid March 2015, I glanced out of my window at about 4 am, to see what appeared to be a very bright total lunar eclipse, as in, the moon was full and ...
6
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2answers
132 views

Acquirable Raw Data in Amateur Astrophotography

What raw data can I possibly acquire from an 8" Classical Dobsonian Telescope, and a DSLR? Could anything eye-opening to amateur astronomers be computed or calculated first-hand with such equipment? ...
2
votes
1answer
158 views

Why does the moon appear on cloudy night sky?

Now, I was looking the sky when I saw the Moon showing up in a sky completely cloudy, like this: But a little different. The clouds were doing an eye shape. What does explain that phenomenon? ...
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2answers
65 views

Can you see pleiades and sirius at the same time on the sky?

I am would like to know if you can see pleiades and sirius on the sky at the same time from Greece? What time of the year would that be? And I would be very greatful if someone knows some interactive ...
1
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1answer
60 views

What were the 2 satellites I saw this morning?

This morning at 6:03am Israel time (3:03 UTC) I saw, simultaneously, what appeared to be 2 satellites streaking across the sky directly overhead. If I remember correctly, they were both coming from NW ...
2
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3answers
161 views

Brightest star of the night sky

I read in many astronomy sites that Sirius is the brightest star of the night sky and that Orion’s Belt points to Sirius. For some days I have been regularly watching Orion (just before dawn) but the ...
5
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3answers
96 views

International Space Station

Recently, I have been going out to observe the ISS when it is within sight of my location. I have noticed that the ISS, based on the time that I have to observe the space station during any given ...