0
votes
0answers
2 views

Internal heat and differentiation

I was reading an article on planetary differentiation, and apparently internal heat producction plays a mojor role. There are several sources of such heat described, such as tidal heat, radiogenic ...
0
votes
1answer
19 views

how to know a short period binary is tidally locked?

Observationally how to know that? Theoretically how to know that? Is there any reference papers to read?
-1
votes
0answers
10 views

Exoplanet Temperature Calculations

I was given an exoplanet similar in size and distance to host star to our own earth. It's orbiting a star with luminosity six times our sun, the greenhouse coefficient 0.3, bond albedo 0.3. I need to ...
-1
votes
1answer
11 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 ...
3
votes
3answers
98 views

Is gravitational energy released when a body contracts?

Kelvin stated that gravitational energy released due to contraction was responsible for the energy radiated in the stars. Although the theory was wrong, was the assumption practically right? If it's ...
1
vote
1answer
46 views

Retrograde motion and Kuiper Belt Objects

As seen from Earth, planets such as Mars and Jupiter exhibit retrograde motion when they are near opposition (from Earth). I am wondering how this effect extends to very distant objects, such as ...
0
votes
0answers
7 views

begining research in astronomy/astrophysics - how to go about [migrated]

I am a (beginner) researcher in the area of Turbulence, Applied Mathematics and Hydrology. I really want (for personal reasons) to start doing some research in the field of Astrophysics/Astronomy but ...
1
vote
1answer
51 views

How to read 5 degree data of green line intensity

When I open the 5 degree data of Green Coronal Emission line from this, I get a weird table which is not simple like the one for Coronal Index. I am only providing the table for 1939. ...
-1
votes
1answer
43 views

When will a day on Earth & Mars be the same length?

I read on Wikipedia that: As on Earth, the period of rotation of Mars (the length of its day) is slowing down. However, this effect is three orders of magnitude smaller than on Earth because the ...
1
vote
3answers
79 views

Temperature of the Sun's rays

What is the temperature of the light that leaves the Sun towards the Earth and does it cool down during it's journey here ? If it doesn't cool down then how come it isn't frying the Earth ? Is it our ...
2
votes
2answers
104 views

Is there any man-made satellite orbiting our moon?

I am just wondering whether any man-made satellites are currently orbiting our Moon. If there is one, would I be able to see it using my telescope?
2
votes
2answers
134 views

Orbiting supermassive black hole or galactic center of mass?

One of the ways they measure the (supposed?) supermassive black hole at the galactic center of the milky way is to measure those tens of stars right at the galactic center that are orbiting what ...
0
votes
1answer
82 views

When we see the Sun, do we actually see its past?

The Sun's rays hit our eyes around 8 minutes after they are emitted from the Sun. Does this mean that the Sun that we see is always the Sun as it was some 8 minutes before? I strongly think this must ...
-3
votes
0answers
29 views

Radius and velocity of Earth's orbit around the Sun [on hold]

How do you find the radius and velocity of Earth's orbit around the Sun?
0
votes
2answers
67 views

What's the relationship between Moon phase and the Milky Way visibility?

I've been using an IOS app to predict visibility of the Milky Way. I'm planning a trip to capture the Milky Way on 9th March 2015, but the app shows the visibility will be very weak on that date. ...
-2
votes
0answers
35 views

Does the Multiverse mean that all the universes are related somehow? How would that work? [on hold]

The Multiverse means that there is a multitude of universes. But does it also mean that if you do something in this universe, the same thing will happen in another universe just in a slightly ...
-5
votes
0answers
45 views

overlapping observable universes

From Wikipedia: The observable universe consists of the galaxies and other matter that can, in principle, be observed from Earth at the present time because light and other signals from these ...
-2
votes
1answer
72 views

Why would a star’s position in the sky change relative to another star right next to it? [closed]

I'm curious about stars and I am wondering why a star would change its position in the sky due to another star right next to it?
3
votes
1answer
44 views

Is the SOI a spherical region or a oblate-spheroid-shaped region?

The Wikipedia article on Sphere of influence states that: "A sphere of influence (SOI) in astrodynamics and astronomy is the oblate-spheroid-shaped region around a celestial body where the ...
6
votes
1answer
487 views

Are there more stars than all the words ever spoken by humans?

A while ago I saw Neil deGrasse Tyson comparing the number of stars in the universe with the number of words spoken by all of humankind, ever since. I realize both of these numbers are not strictly ...
1
vote
1answer
31 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. ...
10
votes
2answers
354 views

Age of the universe and time dilation

Given our knowledge and the standard cosmological model, we estimate that the age of the universe is about 13.7 billion years old. How much sense does it make to talk about the age of the ...
1
vote
1answer
58 views

What are the azimuths of the planets' orbits?

I am creating a virtual solar system model and I want it to be as realistic as possible (e.g. orbits are ellipses, not circles, and orbits are oriented correctly, not all coplanar). In order for me ...
-3
votes
0answers
28 views
3
votes
1answer
76 views

Given a date obtain latitude and longitude where is the sun zenith

Searching is easy to find terminator line (frontier between day and night) or the position of the sun in the sky given a position on the earth and a time; but I can't find how to obtain where is the ...
5
votes
1answer
33 views

How does radio bandwidth restrict the choice and use of science payload on interplanetary probes?

I asked a question here about returning to Earth a physical memory capsule along with soil samples, as a complement to radio operations as today. This might return a much larger amount of data ...
0
votes
2answers
46 views

Is Blue Shift just as provable as Red Shift?

I've heard a lot about red shift and it sounds pretty legit. But it made it sound as if blue shift was a lot less likely. Can anyone help me out?
0
votes
1answer
56 views

How many galaxies are there in the Hercules–Corona Borealis Great Wall?

The Hercules–Corona Borealis Great Wall is "to date (February 16, 2015), it is the largest and the most massive structure known in the observable universe" (source). How many galaxies is the ...
3
votes
1answer
98 views

Why are explosions always used to represent the Big Bang?

In documentaries the Big Bang is often represented as blackness followed by a big explosion with loud noises. This always feels cheap and falling short of explaining the origin of the Universe. Is ...
3
votes
2answers
134 views

How do moons get captured?

[Apologies if this is a duplicate: I feel it ought to be, but my searches have failed]. A moon-sized object is running loose in the Solar System, perhaps after a planetary collision. As it approaches ...
1
vote
0answers
53 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
34 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
134 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
61 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
18 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
59 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
37 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
177 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
29 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
28 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
62 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
470 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
182 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
32 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
64 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. ...

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