6
votes
3answers
602 views

Why is the speed of light 299,792,458 meters/sec?

Ok, I am majoring in physics (4th year) and I never understood this fundamental (kinda) question. Maybe I haven't explored it enough. For example, why does it take 8min20sec for the light from the ...
5
votes
1answer
273 views

Formulas to determine the illuminated phase and orientation of the Moon

The phase of the Moon (the bright limb) looks different depending on where on Earth the observer is located and the time of the observation. I've located this video and the accompanying spreadsheet ...
5
votes
4answers
326 views

Do solar systems have to evolve in a galaxy?

Is it possible for a solar system like ours to exist and evolve apart from all other star systems and galaxies. Sort of like a stand alone solar system or rogue solar system for lack of a better name. ...
1
vote
1answer
87 views

Matter/mass exist into the space. Where does space exist? [duplicate]

It is said that before big bang there was nothing. Not even space/time. So, now where does space exists?
2
votes
2answers
63 views

Is it possible to calculate the time of day given latitude, longitude and solar elevation angles (zenith, azimuth, elevation)?

I am trying to determine the time of day of some images I have. I know the lat/lon, the day and year of image. I also know the 3 solar angles (zenith, azimuth, and elevation). Is there MATLAB or ...
3
votes
2answers
84 views

How many earth-like planets do we know at this moment?

Well, the title says everything... How many earth-like planets have we discovered out there? Discard too big (made of gas), too cold, too hot, etc. Consider earth-like sun distance, size, temperature, ...
2
votes
1answer
92 views

Could black holes be creators of dark matter?

At the tremendous forces of gravity inside a black hole, can "matter" be transformed into a more degenerate form; "dark matter" (if that truly what dark matter is)? I know the inside of a black hole ...
4
votes
2answers
185 views

A clock travelling “faster than the speed of light” [closed]

When a clock travels close to the speed of light as observed by us, it should tick slower. Does this mean that, when using this clock to measure a second - it could travel much more than 300 000 km ...
4
votes
5answers
379 views

What would we find if we could travel 786 trillion light years in any direction

I've sometimes heard of galaxies that are millions or billions of light years away but if we could instantly travel 786 trillion light years in any direction, what are we likely to find? And what if ...
1
vote
0answers
76 views

Integral calculus for the Olympiad? [closed]

This year I am going to participate at the Astronomy Olympiad, in the beta group (seniors) - 15 years old or above. I have already participated at this Olympiad in the alpha group (juniors)... now, a ...
2
votes
3answers
176 views

Do stars have exactly sphere shape?

Planets (at least, some of them like Earth) aren't exactly spherical - but what about stars? Is Sun perfectly spherical, for example? What may be the reasons if it isn't? What about other stars?
1
vote
2answers
174 views

If the earth stopped rotating, would we really fly inertially at 1000mph? [closed]

I heard this on Prof. Neil Tyson's StarTalk podcast (this episode) and had a question about it. In a Q&A session, a listener had asked what would happen if Superman really did stop the earth from ...
3
votes
1answer
63 views

How do one identify something they see in the sky?

I've always wondered how someone looking at the sky into the enormous amount of stars and other things out there figures out that whether it is an already identified object or is he looking at ...
3
votes
1answer
191 views

What would happen if a body were to fall into a neutron star?

We know neutron stars as a very massive object with extremely strong gravitational forces that composes mostly of neutrons. I couldn't help but wonder, what would happen if an object fell into a ...
0
votes
2answers
167 views

What happened before the big bang? [duplicate]

Was there space before big bang? Or who knows there might be different heavenly bodies that we might not perceive?
4
votes
2answers
143 views

Why one cannot escape from a black hole [duplicate]

The usual explanation is that escape velocity of a black hole is above speed of light, therefore nothing can escape because nothing can move faster than light. This is however a fallacy, because ...
2
votes
2answers
231 views

Galaxies are moving away from each other then how Milkyway and Andromeda galaxy coming towards each other?

The Andromeda Galaxy is approaching the Milky Way at about 684000 mi/hours, making it one of the few blueshifted galaxies. The Andromeda Galaxy and the Milky Way are thus expected to collide in about ...
5
votes
1answer
56 views

To what extent are structure formations unexplained?

I hear conflicting claims about our understanding of the structure formation in our universe. I heard that ΛCDM explaines well the large scale structure of the universe i.e. Comparison of the ...
3
votes
1answer
63 views

How is the magnitude of a star measured?

How does one measure the brightness of a star?, I did not find anything on the internet.
4
votes
3answers
742 views

Which planet is also the name of an element? [closed]

Which planet is also the name of an element? I came across this question on cosmos quest and need and answer
1
vote
2answers
113 views

Can we know whether any distant galaxy is moving away in same direction or in opposite direction w.r.t. our galaxy?

The Hubble law states that the recessional velocity of a galaxy is proportional to its distance from us. It takes redshift and angular sizes (for distance) of the galaxy to determine velocity, and ...
7
votes
2answers
902 views

Was the Milky Way ever a quasar?

Is there any evidence that the Milky Way could have been a quasar in it's early history? Is it thought that most galaxies come from quasars?
3
votes
2answers
131 views

What's the origin and culture of funny astronomical terminology?

I'm not in the industry myself, but as an interested member of the public the terminology of astronomy seems a bit funny. Astronomers who today talk publicly about the interstellar medium say that the ...
8
votes
2answers
87 views

Adjust axis labels in ds9

How can I adjust the axis labels in ds9? I'd like to have something like: So far I only managed to get floating points (tl h%f3): or the leading hours are missing (tl h%f1 m): Edit: I tried ...
5
votes
1answer
161 views

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 ...
0
votes
1answer
115 views

Is there going to be a really bad Solar Storm in 2014?

Here are some Articles I've found. Is it true? If it is, How big could it be?, what might be possible or will be possible?, what will happen?
4
votes
2answers
58 views

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 ...
7
votes
1answer
167 views

Do stars of a galaxy change their positions relatively to each other?

Complete astronomy noob over here who would be happy if he get a simple answer (and who is also aware that this may be not possible)... I've learned from a tv documentary that the stars at the edge ...
3
votes
2answers
126 views

Are black holes orbiting around each other?

Obviously, bodies with low gravity force orbit around another one with higher gravity force, if they are close enough to each other. Is it true also for objects like black holes? Are they even able ...
6
votes
4answers
195 views

Can there be a 2nd possibility deduced from the fact that galaxies are moving away from us?

I just read that according to the BBT the universe is expanding. This is evident from the fact that distant stars (and galaxies) are moving away from us. But it could also happen that the universe is ...
1
vote
1answer
54 views

Rotational speeds of the material forming planets should increase, not decrease

We know that planets form as a result of gaseous material revolving around a center of mass that froze to form planets. However shouldn't the angular speed of that matter increase as they go closer to ...
3
votes
3answers
192 views

Why is the outline of a crescent moon brighter?

Some quick googling has given me the answer to whether seeing part of the moon that receives no sunlight is an optical illusion or not: it isn't. Earthshine lights the moon enough for the human eye to ...
2
votes
1answer
155 views

If oxygen was abundant in Neptune, would there be combustion?

Since Neptune/Uranus have high percentages of methane, wouldn't it be highly likely that there will be combustion (triggered by the lightning storms or any other factor) if oxygen was abundant? And ...
2
votes
1answer
101 views

In what form was the space at singularity?

It is somewhat imaginable for all the matter or energy to be condensed in sub-atomic size. But what about space? The space is neither 'matter' nor 'Energy'. If there were no space at singularity ...
2
votes
1answer
53 views

What is needed to break through the surface of Europa? [closed]

How big does a satelite we send have to be to be able to chrush through the ice layer and dive into the ocean on Europa? If a mission should head there, is this a better way of examining the ocean ...
6
votes
4answers
219 views

Why is liquid water considered a requirement for life?

I`ve heard about different extremofiles living on earth. Is water a requirement for life because we have not seen life survive on earth without it, is it a chemical reason which makes life without ...
3
votes
2answers
259 views

Why are distant galaxies not visible in the observable Universe?

Assuming that the Universe is and has been expanding ever since its creation (Big Bang theory), the galaxies that are now at the 'edge' (not visible theoretically) must have been (at some point in ...
1
vote
1answer
64 views

traveling past the speed of light [closed]

According to the theory of relativity (If I understand correctly), nothing is supposed to be able to travel faster then the speed of light. I believe, to my limited knowledge and grasp of the concept, ...
8
votes
1answer
119 views

Any possibility for life on moons of planets in our Solar System

We all focused on our moon, to find water or life, or any thing related to life. But my question is, is there any chance for life in moons of other planets in our solar system, others have too many ...
2
votes
1answer
248 views

If the tilt of the Earth changed, would the tropics latitude change too? [closed]

I wanted to know if the tilt of the earth were changed to 30 degrees would the tropics of cancer and Capricorn also both change to 30 degrees?
2
votes
2answers
224 views

the most accurate system that can show the positions of planets at my birthday [closed]

My birthday : 4 December 1982 If you have such astronomical calculator on your computer please send me the result ! Alternatively if you know an online astronomical service for my purpose please ...
4
votes
2answers
93 views

Acronyms of catalogs in SIMBAD database

How to find acronym of specific catalog in SIMBAD database? For example, I want to select stellar names, object types and all binary stars from "Stellar effective magnetic fields. II." catalog ...
3
votes
1answer
108 views

What's the estimated remaining life of Halley's Comet?

I know that Halley's comet is seen from Earth every 76 years or so since a couple centuries. As it travels, and particularly when it comes near the sun, it loses some of its material (ice). Someday, ...
5
votes
3answers
197 views

Is there anything special about our position in the galaxy thats necessary for life?

It's a fact that our planet's location from our parent star (among other factors) is of crucial importance to the existence of life. But can our position in the galaxy be considered a factor when ...
1
vote
1answer
64 views

What are angular sizes of thin and thick disks in our Galaxy?

What are diapasons of galactic coordinates for thin and thick disks of our Galaxy?
7
votes
1answer
132 views

If we “turned universe upside-down” and changed all matter to anti-matter instantly

...what would be the immediate consequences? Or putting it better, if (from big-bang or whathever), the universe were always made of what we call Anti-matter what would it be? The scientists of this ...
2
votes
1answer
172 views

Star names and the HYG Database

Related to Convert coordinates between RA/dec and WGS 84 (SRID=4326). WARNING: I'm a noob in astronomy. After import all stars from HYG Database (http://www.astronexus.com/node/34) I noticed some ...
5
votes
2answers
116 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?
3
votes
1answer
83 views

Can orbital migration cause a planet to crash into the sun?

If the planets move out of their current orbits into other orbits over long periods of time could this cause a planet to crash into the sun? Maybe the term crash is a little dramatic, could the orbit ...
3
votes
1answer
83 views

Motion of rogue planets

Two Questions: 1) Are rogue planets in motion, i.e. are they just wandering freely in space or stationary? 1) Do rogue planets have defined path or a one which can be anticipated? I understand that ...

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