4
votes
1answer
115 views

Does the universe expand at the same rate everywhere in the universe?

Specifically, I am wondering if some areas of the universe expand faster than other areas and whether the faster expanding areas diffuse the expansion through the slower expanding areas or does the ...
1
vote
1answer
32 views

Amount of EM radiation (and particles) Earth “receives” from other planets in our solar system?

Can it be (or has it been already?) measured how much and what kind of EM radiation (apart from visible light)/particles Earth "receives" from a specific planet in our solar system? Can other planets ...
3
votes
2answers
445 views

How to calculate the moon phase [duplicate]

I need a way of to calculate the moon phase. Do you know resources for research the theory from behind this? I basically have searched in Google, but the results were not very satisfactory. Exists a ...
5
votes
2answers
138 views

Standard practices and models for generating the ephemerides of the solar system

I am familiar with the theory on generating the positions of the members of the solar system, but have been unable to find out the standard practices and methods of professional astronomers in ...
2
votes
1answer
78 views

Roll, Pitch and Yaw of Orbital Planes

I have been reading about celestial mechanics and particularly about planetary orbits. I understand that a planet's orbit can be tilted (pitched) with respect to the Earth's ecliptic and that it might ...
-2
votes
1answer
95 views

What if the earth stopped rotating and revolving at the same time? [closed]

What will happen to us are we going to move in a tangential direction with earth axis of rotation ?
2
votes
1answer
185 views

What are iron stars?

I have a question about iron stars. I was fascinated about the theory about the inability of protons to decay, and it led me to a point where I read something about some special kind of star called an ...
4
votes
1answer
139 views

What causes the aurora of other planets to have different colors?

All I could come up with is it depends on the atmospheric composition of the planet as they will interact with the charged solar particles which might be true but is there is there a definite reason ...
2
votes
2answers
247 views

Can things move faster than light inside the event horizon of a black hole?

Black Holes are regions of space where things get weird [Citation Needed]. Past the event horizon of a black hole, any moving particle instantaneously experiences a gravitational acceleration towards ...
2
votes
1answer
79 views

Spicules vs Prominences/filaments

What is the difference between spicules and prominences/filaments. I know that they are both in the chromosphere, and I know the difference between provinces and filaments (depends on the view), but ...
3
votes
2answers
196 views

Can the Sun become a big ball of gold atoms?

The atoms inside the core of sun are continuously fusing and forming other atoms. Can this continuous fusing make gold atoms?
5
votes
1answer
308 views

Astrophotography - Unable to achieve focus with current setup

I am new to astrophotography and am looking for guidance. I have the following equipment: Orion StarBlast 9814 4.5" Altazimuth Reflector Tabletop telescope 1.25in Telescope Adapter Extension Tube T ...
6
votes
2answers
56 views

Is the Astronomy community still concerned about the lumpyness of matter distribution in the universe?

A decade or so ago, when I was still a science undergrad, one of the open questions in astrophysics was to explain the uneven distribution of galaxies in the observable universe. That is, why did the ...
1
vote
2answers
58 views

Real-time position of a distant celestial body

How might it be possible to determine (via some specific online empemeris or via some well-understood algorithm) the observed position of some distant celestial body (e.g. Betelgeuse)? To be ...
1
vote
1answer
53 views

Finding the suns position in the sky anywhere at any time

What am I looking for? from any point Latitude, Longitude and date D I want to know where the sun is in the sky at any given time anywhere on our planet. I even don't know what the outcome will be ...
2
votes
1answer
67 views

Sun's apparent motion above the arctic circle during summer solstice

I'm having difficulty with an apparent contradiction about the sun's motion during the summer solstice above the arctic circle. The YouTube video The North Pole Entire Summer of never ending sun ...
4
votes
1answer
88 views

What's the distribution curve for meteor sightings?

I know that meteor showers have a "peak" observation time. What does the distribution in time look like? Is one side of the peak steeper/shallower or longer/shorter than the other side, and if so, ...
2
votes
1answer
44 views

stellar metallicity

I saw a talk recently mentioning that another factor that may determine a star's metallicity (besides age) may be how far from the center of its "birth cluster" it is when the short lived hot central ...
1
vote
1answer
81 views

What is a Seyfert galaxy?

I know Seyfert galaxies are types of active galaxies, but I do not understand what separates them from other types of active galaxies. Are they brighter/not as bright as other types of active ...
9
votes
2answers
2k views

Is it possible to witness a star's death?

Given that the stars' distances to Earth are measured in light-years (for example, Sirius is 8.6 light-years away from Earth), what we are seeing as Sirius now is actually its state 8.6 years ago, ...
0
votes
1answer
30 views

Road map for a faster spaceship [closed]

New Horizons, speediest yet, is currently running at about 15 km/sec relative to the sun. What is the roadmap for future ? How is it possible to reach much faster speeds ?
2
votes
1answer
223 views

The dark side of the moon [duplicate]

I encountered this statement that the dark side of the moon is hidden from our sights. Could someone please explain?
4
votes
2answers
106 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 ...
1
vote
1answer
184 views

When will the next summer solstice and a full moon coincide? What day?

What day will the summer solstice and full moon coincide? As far as I know the next time will be in 2016. I would like to know what day.
4
votes
2answers
1k views

Does a black hole become a normal star again?

Stars which satisfy the Chandrasekhar limit can become a black hole. What happens to star after it becomes a black hole? Does it regain its status of star?
2
votes
2answers
94 views

What is faster than a supernova explosion?

Is a supernova explosion really fast or is it just fast, metaphorically speaking? Can you cite the fastest known phenomenon in astronomy (neutron stars, pulsars) besides supernovae in terms of ...
4
votes
2answers
110 views

Do most planetary systems have fewer planets than the solar system?

It is my impression that most planetary systems have, at most, three to four planets. Is that real? Or is it just that we lack the ability to detect most planets?
4
votes
2answers
102 views

Gravitational lensing in Newtonian physics

Famously, when Eddington attempted to measure gravitational lensing during the Eclipse, it was the measured magnitude of the lensing that gave gravity [pun, obviously, intended] to General Relativity ...
6
votes
2answers
151 views

Likelihood of a stable system with a dwarf planet's orbit inside that of a gas giant

I keep thinking of various planetary system configurations, and would like to know: What are the fundamental references based on Monte Carlo long-term simulation of planetary systems' evolution that ...
2
votes
1answer
55 views

Why are there no Oe or Ae stars?

The unique characteristics of Be stars are mainly because of their circumstellar discs. I wonder what makes Be stars special that only they have unique characteristics? Which kind of stars have discs ...
0
votes
2answers
30 views

Simulating location of the moon

I'm researching high altitude photography and want to know a schedule for taking pictures of the moon. Preferably I want a picture of the (full) moon on the horizon. How would I go about scheduling ...
2
votes
1answer
56 views

Does tidal heating imply orbit degradation?

What compensate the energy loss in tidal heating? Is it orbital decay?
20
votes
4answers
2k views

Where does the Solar System end?

This is a question I've heard many times in the past, and a quick search of the site says it hasn't been asked here, so I figured I might as well ask (and answer) it. I know that it is rare for ...
3
votes
1answer
60 views

Ultra Low Cost Telescope Project

A few years or so ago there was a project that distributed small very low cost telescopes (perhaps around US$20). What was the name of (and links to) that project?
0
votes
0answers
24 views

Units of angular power spectrum

I am not sure whether this question might be better suited for crossvalidated or stackoverflow, but I will give it a try here: I have a map of the full sky in in the healpix format, units are $\rm ...
2
votes
1answer
36 views

IAU Dwarf planet definition Point 2.b - is not a satellite

I am a bit confused with point 2.d of the IAU's resolution on dwarf planets. (2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun (b) has sufficient mass for its ...
1
vote
1answer
73 views

How long will it take to reach the closest earth like planet

Using the engines today how long will take humanity to reach earth like planets?
2
votes
1answer
65 views

Any tip on maintaining a log of celestial objects?

I am an amateur observer and Olympus 10x50 binocular is my tool. As I keep locating celestial objects (Planets, Stars etc), I would like to maintain a log of the observed objects. The purpose of the ...
2
votes
1answer
74 views

Why are there no more images revealed by New Horizon?

Since a few days after the flyby there are no more images published on the NASA page. Why is NASA waiting to publish any more images for some reason? Or is there something happened to New Horizon?
1
vote
1answer
70 views

What is the largest possible size for a brown dwarf?

What is the largest possible size for a brown dwarf before it has enough mass, capable of sustained fusion, thus becoming a star?
1
vote
1answer
98 views

What was the orbit of the meteor that impacted the Moon on 2013 September 11?

On 2013 September 11th, a meteor impacted the Moon leaving a 34-meter crater. So far the only info I've found was from youtube (https://www.youtube.com/watch?v=zCFDkj2JtyA) and this site: ...
2
votes
1answer
34 views

how to assess a periodical signal?

After folding a light curve, we may get some kind of shape. How to tell whether there is a real periodical signal quantifiably? The fluctuation may be small, and the folded shape may not be perfect. ...
2
votes
2answers
122 views

Can I measure the moon's gravity?

Since I learned about Newton's gravity law, I wonder if I can measure the moon's gravity using (almost) no special equipment. The best I could come up with is a pendulum, which is in a resting ...
6
votes
2answers
722 views

How is a non-rotating black hole created

How are non-rotating black holes formed? I guess that non-rotating black holes are formed from non-rotating stars but I couldn't find any proof that such a star exists on the internet. If this is ...
6
votes
2answers
216 views

Has the conjunction between Venus, Jupiter, and Regulus only occurred twice in 2,000 years?

I recently heard the claim that mid-July, the "Star of Bethlehem" formed for the first time in 2,000 years, where the Star of Bethlehem is a three-way conjunction between Venus, Jupiter, and Regulus. ...
1
vote
2answers
55 views

L4 and L5 stability

For what I know, L4 and L5 are high points. Although, they are stable points. Why? I thought it was the same being a high point and being a unstable point. If I'm off-topic, please let me know where ...
7
votes
2answers
960 views

What is the standard reference point for measuring speed?

Speed, as we know, doesn't exist without first having a reference point. We then say that the reference point isn't moving at all, and speed is then measured in relation to the reference point. What ...
2
votes
1answer
77 views

What is the highest recorded temperature in space

What is the highest recorded temperature in space? I'm not asking about Planck temperature that is a fraction of a second before the Big Bang. I'm asking about the temperature that has been recorded ...
0
votes
1answer
142 views

What makes the moon, a super moon

Caught a sight of moon tonight (by chance) and came in surprise that moon looks thrice in size to its usual size. Mostly called as Blue moon. Didn't succeed in getting the details and explanations ...
0
votes
0answers
22 views

Can the explosion of a supernova destroy the Earth? [duplicate]

If there anywhere in near space a supernova that can destroy Earth? Not by the gamma-ray, but literally by supernova explosion itself?

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