5
votes
2answers
106 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
35 views

Heavy bombardment - Why has things cooled?

I was always taught and lead to believe that at the beginning of our solar system, there was a period of heavy bombardment, which is conceivable. Why has it just stopped and we are at peace from ...
2
votes
0answers
50 views

Is light bending around my finger? [closed]

I was hoping that astronomy enthusiasts/scientists would help me out with a simple question about light. Hold your outstretched hand up to any bright light source (the sun, or even a light bulb) so ...
1
vote
2answers
111 views

Would Venus have any significant effects on Earth if its orbit were entirely within the habitable zone?

If Venus was entirely inside the habitable zone, or life zone, would its proximity to the Earth provoke any remarkable changes to the Earth?
9
votes
1answer
121 views

Where is all the antimatter?

The universe supposedly started off with equal parts matter and antimatter and they are said to annihilate each other. Also, nature is famous for it's balance between everything. So all we see is ...
2
votes
2answers
60 views

Absolute magnitudes of stars

Where to find comprehensive list of absolute magnitudes for stars of different spectral types? I need published paper or web page with data and reference to the source.
2
votes
1answer
33 views

What would the sky have looked like when galaxies first started to form?

If I stood on a theoretical earth at the time that galaxies were just starting to form, what would the sky have looked like? Due to the smaller size of the universe would it have been densely packed ...
4
votes
1answer
41 views

Are many exoplanets synchronously tidally locked like Mercury?

The only tidally locked planet in the Solar system i Mercury. But it is synchronously tidally locked 3:2, because of the relatively high eccentricity of its orbit, so doesn't turn the same side ...
3
votes
0answers
47 views

What is that void that the universe is growing into? [duplicate]

We understand that this is the universe and it is essentially full of space and time, but what is on the outside of the universe, and isn't that nothing, something, and how far does that reach. I.e. ...
5
votes
1answer
111 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 ...
2
votes
2answers
104 views

Is everything quantum entangled?

So, I am learning about quantum entanglement in my quantum course and had a thought. If the Big Bang is the creation of everything - time included, and this came from a single "source". Would it not ...
2
votes
1answer
61 views

Why doesn't the earth's surface collapse onto itself? [closed]

From what I know the sun (or any other star) nuclear fission keeps it from collapsing under its own gravity until the fuel runs out, if that's so why doesn't the earth surface like the tectonic plates ...
2
votes
1answer
35 views

What method is used to calculate the 'quality' of a solar/planetary image?

What sort of algorithm is used to calculate the relative quality of an image, such as is performed by PIPP, Registax, or Avistack? Such applications take planetary or solar images and prior to ...
4
votes
2answers
59 views

Location on (or in) the celestial sphere

First off, I apologize if I am breaking any site-etiquitte. Secondly, this is probably extremely elementary. For a lab, I was given the question: When we are sitting in a planetarium, where are ...
2
votes
2answers
47 views

regarding curvature of earth [closed]

i am having one doubt in earth's curvature.....this question may be dumb... How much we need to travel on earth to feel the curvature of earth. hypothetical case: for ex we are building a vehicle ...
4
votes
5answers
566 views

Did atoms in human body indeed come from stars?

I think I am not alone who saw videos about that we (humans) are made of same atoms which someday were in stars. In other words, some atoms in our bodies are from stars which exploded billions of ...
2
votes
2answers
69 views

Why do objects burn when they enter earth's atmosphere?

Why do all objects burn when they enter our atmosphere? is this because of our atmosphere composition? and does this happen on other planets as well?
1
vote
2answers
43 views

Can redshift be measured using fourier?

Are there pictures that contain high enough dynamic width, so that amateurs can use fourier spectrum analysis to observe the redshift themselves? I know pictures usually are encoded using RGB and/or ...
2
votes
1answer
53 views

if the big bang only expanded the universe when and how did it originate? [duplicate]

If the big bang expanded the universe from a singularity point, that means that there was matter before, so where and how did matter form for the first time if it's even possible to know such a thing? ...
1
vote
1answer
19 views

How can we infer the mass of SMBH in galaxies that are not active anymore?

I know it is possible to infer the mass of a supermassive black hole (SMBH) by many methods, i.e., stellar orbits for out Galaxy, Iron line profile from the accretion disk, and probably other methods ...
3
votes
2answers
133 views

Do black holes die?

I know of stars actually dying (exploding as a supernova) but I have never heard of what happen to black holes. Do they continue to live forever, waiting there for more matter to absorb? Do they ...
1
vote
5answers
104 views

Can someone explain a Geostationary Orbit in a simpler way?

According to Wikipedia (link), a geostationary orbit, geostationary Earth orbit or geosynchronous equatorial orbit (GEO), is a circular orbit 35,786 kilometres (22,236 mi) above the Earth's equator ...
4
votes
1answer
44 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 ...
5
votes
1answer
55 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 ...
3
votes
2answers
116 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 ...
9
votes
3answers
329 views

What is the distance that the Moon travels during one orbit around the Earth?

What is the distance that the Moon covers in one orbit around the Earth, and does it always take the same amount of time, or does it fractionally differ on each revolution?
-1
votes
2answers
52 views

If NASA is going to capture an asteroid with a spacecraft, wouldn't a UFO be able to manuever a celestial body? [closed]

This article got me thinking If NASA is going to use our primitive space exploration technology to capture an asteroid wouldn't an Extra Terrestrial species have used UFO's to maneuver celestial ...
1
vote
1answer
70 views

strange moonset around 10 pm (3.2 2014, NZ) - explanation?

during a visit to New Zealand we observed (on 3.2 2014) a strange moonset in Te Anau. Around 10 pm, shortly after sunset, the moon appeared, but then quickly began to go down, and about 1 hour or ...
7
votes
2answers
192 views

Why haven't Earth and Venus got any tiny moons? Or have they?

Why haven't some meteoroids gotten caught in Earth's or Venus' orbit? AFAIK most meteors are tiny fragments from comets. Shouldn't some comet tail sometime have passed Earth orbit at velocities ...
4
votes
2answers
111 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 ...
0
votes
1answer
42 views

Could I create a staircase to the moon and walk to it? [closed]

Assuming one could create a staircase and walk to the moon, would escape velocity still be a factor in leaving the Earth's gravitational pull? I'm not a physicist but am just curious to know.
3
votes
1answer
43 views

What are the concrete technical arguments supporting the idea that the wave function of the universe can be written as partition function?

In this talk, the not yet settled down idea that the wave function of the universe could potentially be written as the partition function of a scale invariant statistical field theory is mentioned: ...
2
votes
0answers
23 views

Can we only see the past of the universe? [duplicate]

So I was reading some interesting stuff about universe and Big Bang and wanted to make sure one thing. As far as I understand everything we can see about universe is the past, right? I mean all the ...
2
votes
1answer
54 views

What would happen if we put a small part of White Dwarf or Neutron Star on Earth?

I would know what would happen if we put a small part (let me assume 1 cm$^3$) of White Dwarf or Neutron Star on ...
2
votes
1answer
55 views

What does black hole evaporation correspond to in the accelerating universe / black hole analogy?

In the same way, as a black hole emits Hawking radiation corresponding to its temperature $$ T = \frac{\hbar}{r_{BH}} $$ the accelerating universe can be described as all of the stuff falling ...
2
votes
1answer
49 views

What are the masses of the two stars (given the information provided)?

If anyone would at least be willing to point me in the direction of finding the answer, or help me solve it I'd appreciate it. I don't know how to go about this, and need to know how to solve this on ...
2
votes
2answers
42 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
54 views

How are rogue planets discovered?

Planets are usually found by observing a star and waiting for the light level to drop when a planet passes in front of it, but what about rogue planets that don't have host stars?
1
vote
0answers
50 views

Class presentation on the Sun, ideas? [closed]

Tomorrow I have to give a [high school] class presentation on a topic of the solar system. I have thought of the Sun, as I have always believed it to be the central part of the Solar System. So I am ...
1
vote
1answer
48 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?
3
votes
3answers
93 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
53 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
1answer
60 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 ...
2
votes
3answers
91 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?
3
votes
1answer
46 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, ...
1
vote
2answers
74 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
102 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 ...
4
votes
3answers
389 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
3
votes
1answer
47 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 ...
0
votes
2answers
76 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?

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