1
vote
0answers
58 views

Fourier Transform of Galaxy Images

I'm working on detecting optically overlapping galaxies for future astronomical surveys. I'm looking into feature extraction for HST images and have been computing the fourier transform of images in ...
1
vote
1answer
38 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. ...
2
votes
1answer
141 views

How bright was Scholz when is passed near the Sun 70,000 years ago?

I just read that a star called Scholz passed only 0.8 years-light away from us 70,000 years ago. It is a red dwarf. I don´t know how bright it was in the night sky. Does someone know how bright it ...
2
votes
2answers
62 views

Would a killer asteroid shattered into thousands of pieces produce the same devastation?

If we blow up a global killer (in the 3 - 20km range) days before impact into enough pieces that none of the them exceeds, let's say, a 30m diameter and the impact pattern is dispersed over most of ...
1
vote
1answer
20 views

Relationship between temperature of nebula and size of star

I was wondering, in the process of star formation, does the temperature of the nebula that produces a star play a role in the size of that star? I mean, it's only logical that the size would depend on ...
-3
votes
2answers
60 views

How dense would planet earth have to be to have the same gravity as Jupiter?

I was reading this question about how small could a planet be while having earth-like gravitational pull. This got me thinking, how dense would planet Earth have ...
-1
votes
0answers
38 views

Is it a satellite [closed]

I'm relatively new to amateur observing, and I recently got to use my Celestron mid-level computerized scope (Nexstar 127slt) in a rural area. On two of the nights it was pointing at different places ...
0
votes
2answers
182 views

Do planets repel?

I know gravity is the result of mass. Gravity is nothing but the attractive force on a body due to its mass. I have a question that may be silly. In magnetism we have attraction and repulsion. Earth ...
1
vote
1answer
31 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 ...
1
vote
1answer
29 views

How to view Jupiter with 4.5" Newtonian Reflector

I have a 4.5" Newtonian Reflector and I took a look at Jupiter the other night. I was able to get a reasonably sharp view of it and see a number of it's moons, but I was unable to see any surface ...
-1
votes
1answer
24 views

Could a magnetars magnetic field have saved Mars atmosphere?

Just wondering: if a magnetar was close enough to Mars would it have saved its atmosphere by protecting it from solar radiation? I was wondering this because Earth protects us via a magnetic field; ...
-5
votes
1answer
65 views

Why are a few things in our universe named after chocolate? [closed]

Like the title says, why are a few things in our universe named after chocolate? For example, there are the Milky Way, galaxy and Mars. Is there a reason for this or not? Or is it that the ...
0
votes
2answers
63 views

Can Magnetars destroy planets?

Magnetars are the most magnetic things in our universe. Because of how powerful their magnetic fields are, they could split every single atom apart from each other in our body. Because of this could ...
11
votes
3answers
472 views

Why can't we observe the Oort cloud with a telescope?

The Oort cloud is a hypothetical structure based on our observation of long-period comets. There are currently proposals to design probes to confirm the existence of the Oort cloud. Now, sending a ...
0
votes
1answer
67 views

Declination and Ascension - the Sun and Andromeda

If Andromeda is overhead at midnight, what is the right ascension of the sun? (andromeda is ar RA =1hr, Dec = +40). I thought I understood what Dec and RA were, but I can't think of how to start this ...
1
vote
1answer
183 views

What happens to a white dwarf past the Chandrasekhar limit?

This is a multiple choice question I had trouble with on an exam. Will a white dwarf that has had too much mass piled on top of it a) undergo a thermonuclear flash and explode in a type IA supernova ...
0
votes
1answer
35 views

Telescope size to detect Ceres (Newtonian)

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

Is there a general term for epicycles, deferents, and eccentrics in Ptolemaic astronomy?

According to Ptolemy's (c. 150 CE) account of the motions of planets, planets moved in circular paths ("epicycles") around center points that in turn moved around the center of the earth along a path ...
0
votes
1answer
65 views

Shouldn't all moon orbits be inherently unstable?

A hypothetical simulation starts with a planet called Earth in a perfectly circular orbit around a star called Sol. There is also a moon called Luna in a perfectly circular orbit around Earth. ...
1
vote
1answer
79 views

Could a close passing star be captured by the Sun's gravity?

Earlier I read an article here stating that a binary pair of stars passed within 0.8 light years from the sun. That made we wonder why the stars weren't captured by the Sun's gravity since the sun's ...
0
votes
3answers
85 views

What is our universe expanding into?

From inflation theory and other theories explaining the birth of the universe, the universe is expanding and recently it's been discovered that the expansion has been accelerating. My question is ...
1
vote
3answers
93 views

Can planets inside the Earth's orbit around the Sun appear to undergo retrograde motion?

Retrograde motion is: The apparent motion of the planets when they appear to move backward (from east to west) from the direction that they move ordinarily with respect to the stars. Can planets ...
0
votes
3answers
237 views

Why did the big bang not just produce a big black hole?

Questions I've often wondered about: 1) If all the matter and energy were concentrated at a single point at the big bang, why wasn't that a black hole, or why didn't it form one? 2) If the reason #1 ...
0
votes
1answer
55 views

Is a black hole a 5 dimensional vortex?

We know that a black hole behaves like a whirlpool or a tornado or any of the other rotating phenomena we experience on Earth.But the thing is, all these phenomena, except the black hole, are ...
2
votes
0answers
31 views

Radio Astronomy and Imaging

So, I've been starting to investigate radio astronomy, and am wondering about if certain things are possible from an amateur standpoint. I was looking at this powerpoint(that discusses building a tiny ...
0
votes
0answers
23 views

What significance does coincidence or luck have in astronomy?

Astronomy is basically about looking around, and what happens to be there is very important for what we are able to discover. To what degree is astronomy shaped by coincidences in our neighborhood? ...
1
vote
2answers
42 views

What is a possible software for simulating binary star systems?

I would like to define both initial velocities and masses of components so that orbits may be either elliptical of hyperbolic. Is there any software to make such simulation? Unfortunately, Binary ...
1
vote
1answer
58 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, ...
7
votes
3answers
430 views

Where does the Milky Way end?

I was reading this article and it says the following: Researchers measured the mass of the Milky Way and found that our galaxy is approximately half the weight of a neighbouring galaxy known as ...
4
votes
3answers
113 views

Why are all quasars so far away?

Why are all quasars so far away? If the universe is homogeneous, we could expect to have a homogeneous distribution of quasars, but all of then seem to be far away from Earth. Why is that?
1
vote
2answers
50 views

Why does radio astronomy offer higher resolution images than optical?

According to this lecture,"Radio astronomy has several advantages over optical astronomy...We can make the highest resolution images, and see things happening on the smallest scales." Why is this? If ...
5
votes
4answers
628 views

Did we ever actually see the earth revolving around the sun? Is the geocentric model completely disproved?

Did we ever actually see the Earth revolving around the Sun? Also, is the geocentric model completely disproved or was it sidelined because the heliocentric model made things easier to understand? ...
0
votes
2answers
29 views

Which eyepieces I can use it for best viewing experience using my exisiting telescope?

Telescope: Orion 09843 SpaceProbe 3,3 inch aperture(76mm), 700mm focal length, eyepieces - 25mm and 10mm focal lengths Hi, I am very happy and excited to see moon craters, jupiter and saturn. And ...
0
votes
1answer
32 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?
1
vote
3answers
35 views

How to find RA 0

I am standing in an open area and can see the sky for a full 360 degrees. I have the coordinates of an object (RA and DEC). Where do I look to find RA 0?
1
vote
1answer
72 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 ...
-1
votes
1answer
49 views

What is the acceleration of the stars' speed in the Universe? Positive or negative? [closed]

I have read quite different opinions about that, so can someone tell me what is the sign of the acceleration of the stars in the Universe if we accept that the center of the Universe is the beginning ...
4
votes
3answers
142 views

Is there a flaw with the newer purposes and correlations attributed to the HR diagram? (And would a third axis of mass correct the enclosed flaw?)

When I was younger, I was looking at HR diagrams, and began to experiment with the HR diagram. I was looking at plotting different groups of stars on the HR diagram when I found RV Tauri stars. ...
5
votes
2answers
343 views

Where do the heavier elements come from?

Partly inspired by this question, the end result of stellar fusion is Iron-56 (eventually, after some decay). Then it explodes. How/where then to the heavier elements come from. The answer here ...
4
votes
1answer
91 views

Estimating the angle covered by the star trails and deducing how long the exposure lasted

How would you estimate the angle covered by the star trails and deduce how long the exposure lasted in the following image? Here is the photo's caption: Star trails beyond the Gemini ...
1
vote
1answer
30 views

Did I see a meteor or a re-entry?

Last night (January 21, possibly 5:30 UTC), from my house in northern California, I saw a moving point of light in the sky, going west to east, crossing about 120 degrees of sky in 5 seconds or so. ...
6
votes
2answers
1k views

Is Sun a part of a binary system?

Does our Sun have a counterpart, i.e., is it a part of a binary-system? If so, how does the other star look like and where is it?
16
votes
4answers
4k views

If Jupiter is a gas-giant then why don't its features change?

A naive question. When we look at Jupiter, we see that its features didn't change largely over many years, for instance, the red-spot. If it is composed of gases and liquids, then why aren't the ...
0
votes
0answers
18 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 ...
1
vote
1answer
35 views

How do I get from Star Atlas to real life?

This question is about finding the elevation and bearing of a given star at a particular time at Latitude 52N. I look up the RA and Declination of my star. How do I calculate its RA and elevation at ...
15
votes
6answers
3k views

Why can't we see distant galaxies with the naked eye?

If light keeps travelling in a straight line, why can't we see distant galaxies with the naked eye? Surely if you stared long enough, the light from them would eventually hit your eye? I apologize if ...
1
vote
2answers
131 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 ...
6
votes
2answers
941 views

If Venus and Mars changed places, would we then have 3 habitable planets?

This is the supposition: Venus is too hot, Mars is too cold. If they switched places then Solar energy would change to make both more Earth like. We might as well have had three instead of just one ...
1
vote
1answer
41 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 ...
1
vote
1answer
86 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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