-1
votes
0answers
6 views

What is a Quasar?

The question came to my mind reading this question What is a Quasar ? Have we a clear definition ? Is there any conditions for a SMBH to be "classified" as such ?
0
votes
0answers
4 views

Spinning black hole vs non spinning black hole

Does a spinning black hole have a stronger gravity than a non spinning one.After all, a spinning black hole is stretching space-time more, so does that make a difference is gravity?
1
vote
1answer
19 views

Can a black hole rip spacetime

Can a black hole which has an enormous mass and spins so fast cause spacetime to to be stretched to is absolute limits that it start so rip?
1
vote
1answer
6 views

Quantum Mechanics after Gravitational Waves detection

Of course everyone knows by now the detection of Gravitational waves (http://www.iflscience.com/space/gravitational-waves-observed-first-time) But, since General Relativity and Quantum Mechanics ...
1
vote
1answer
9 views

Measuring time and distance in space

When reading through articles about discovering gravitational waves, I got basic understanding of events that happened. But one thing wasn't clear for me. They say that two black holes collided 1.3 ...
0
votes
0answers
5 views

Is there a connection between Space-Time Vortex and gravitational waves?

Is there a connection between "Frame dragging" (as described in this video about the Space-Time Vortex around the Earth) and gravitational waves? Is rotation of a mass an necessary or sufficient ...
0
votes
1answer
4 views

How to compensate the effect of tectonic activity in devices like LIGO?

In late 2015, the LIGO project team announced the detection of gravitational waves. The detector is (very basically) a laser measuring the distance between two mirrors in vacuum, over a large-enough ...
2
votes
2answers
10 views

Why is the detection of gravitational waves such a “Big” deal?

I'm a non-scientist. Today's announcement of LIGO's detection of GW waves has been heralded as "huge" –on the same level as the Higgs Boson detection. I realize this is the last remaining part of ...
-1
votes
1answer
17 views

Is it possible to get a glimpse of the Big Bang through gravitation waves?

I read in an article announcing the detection of gravitational waves by LIGO that it will be possible to detect them from the Big Bang. Is this true?
1
vote
0answers
29 views

The black hole binary that was detected by advanced LIGO - how do such hypergiant binaries form?

With today's announcement of the historic detection of gravitational waves from the merger of 36 solar mass and 29 solar mass black holes 1.3 billion light years away, one can not help but wonder how ...
0
votes
0answers
24 views

Are there other universes? [duplicate]

Our universe is a very unlikely place. Alter some of its settings even slightly and life as we know it becomes impossible. In an attempt to unravel this "fine-tuning" problem, physicists are ...
1
vote
2answers
33 views

Where can I watch the announcement from LIGO about gravitational waves?

Today the LIGO consortium are having a press conference to update us on their search for gravitational waves. How should I watch the announcement?
0
votes
0answers
13 views

Bright lines in a continuum spectrum

Dark lines in a continuum spectrum is common. But are there bright lines too? By the stimulated emission process, the light can also be amplified, right? In this case, we should get bright lines ...
0
votes
1answer
44 views

Multiple aerobraking

I moved this question to more related : Space exploration I spent a lot hours with Kerbal Space Program recently and I am courious about one thing. I got into orbit of moon and then I was able to ...
1
vote
1answer
15 views

What Are Some Good Southern Hemisphere 7x50 Binocular Targets?

I've been interested in astronomy for a while but only recently purchased my first set of binoculars (7x50). I've been learning various constellations as well as spotting some other objects with the ...
4
votes
1answer
46 views

What is driving the expansion of the Universe?

Is it just the momentum from the Big Bang? If yes, how can it account for the acceleration of the expansion? Why isn't the collective gravitational force slowing it down? What part does dark energy ...
1
vote
2answers
29 views

Is the colour of a wave from a far galaxy the same for us as for a galaxy which lies between?

Because of the expansion of the universe, light from a far galaxy is redshifted. The expansion of the universe will make the wavelength of light longer. But is the colour of such light the same for ...
-2
votes
0answers
54 views

energy can neither be created nor destroyed [on hold]

I've studied that energy cannot be destroyed,but when light is absorbed by black hole then it is destroyed because there is a theory that when light enters the black hole,some times it may transported ...
2
votes
2answers
82 views

Why is it said that the far side of the moon's crust is thicker?

This video states that NASA has determined that the far side of the moon's crust is thicker than the near side's crust. How did they determine this? Please note I'm not asking for theories or ...
3
votes
2answers
56 views

Why do planets move in an elliptical orbit?

I am a student of class 9 and recently came to know about kepler's law of planetary motion and got confused about the foci and elliptical orbits of planets and some stars.
3
votes
1answer
312 views

Where do new stars get their hydrogen from? [duplicate]

When stars run out of hydrogen, they explode (though they also use heavier elements for some time) and form nebulae. In the nebulae, new stars are born which use hydrogen as their fuel. So, my ...
0
votes
0answers
30 views

How does the electric universe theory see the repelling forces happening in universe?

The Electric Universe Theory (EUT) explains why gravitational forces aren't real and not needed because these forces can also be explained by electromagnetic forces. But using these electromagnetic ...
1
vote
1answer
98 views

What do gravitational waves allow us to understand?

Before reading this question, you should read this paper. From what I understood, we managed to detect gravitational waves for the first time. Is this discovery going to help us understand ...
6
votes
1answer
365 views

How do star densities work?

If we take a look at stars more massive than the Sun, their densities vary a lot. UY Scuti is an extremely low-density star that's only 8.5x more massive than the Sun, but is 1000-2000x its size. ...
1
vote
0answers
22 views

What would we not know without spectroscopy?

What do we depend on spectroscopy to know about in astrophysics? Or, without spectroscopy, what would remain unknown to us? I want to know how important it is. My wife is studying spectroscopy in ...
0
votes
0answers
6 views

Convert axis display in ds9

I have a fits file of an echellogram with the axes showing the pixel indices. However, I would like to convert my horizontal axis from pixel to wavelength given that I have a conversion formula for ...
4
votes
1answer
45 views

Why do pre-main sequence stars show lithium in absorption?

This paper and this paper state without discussion that the presence of lithium absorption in the stars they observe as strong evidence of these stars being pre-main sequence stars. Because they state ...
0
votes
1answer
28 views

Determining distance from semi-major axis and eccentricity

I am trying to obtain the distance covered by an object in orbit around the earth within a specified amount of time past its perigee passage. The object is in an elliptical orbit with eccentricity 0.2 ...
1
vote
1answer
41 views

Why does mass naturally move closer toward's the center of other masses?

If general relativity is understood to mean that mass curves space such that objects are still traveling in a straight line, why does mass naturally move closer toward's the center of other masses?
7
votes
2answers
59 views

What conditions would lead to this event around the black hole in the Pictor A galaxy?

This is a picture of a jet of particles exiting the supermassive black hole in the center of Pictor A galaxy at nearly the speed of light. Source This event is supposedly created from a black hole ...
-1
votes
2answers
37 views

Is parallel universe possible [duplicate]

Does parallel universe really exists or just science fiction which ain't possible? Can we ever know ?
0
votes
1answer
34 views

What was the entity/particle/state at the time of the Big bang?

At the time of the big bang if there was an original entity, what were it's attributes(if applicable) - mass, electric charge, color charge or spin? Can the current matter and dark energy together ...
0
votes
0answers
22 views

Is there any support for the Big Crunch Theory? Could there have been a partial Big Crunch in the past?

Is there proof in either the CMB or other observed astronomical phenomena for Big Crunch? Could there have been a partial Big Crunch maybe like a cluster of Black Holes colluding to create a ...
0
votes
0answers
11 views

Are there any studies that prove/disprove the Oscillating Universe Theory?

Can anyone cite some studies that provided proof of events/phenomena that either prove or disprove the theory?
1
vote
0answers
22 views

Is it observable what is the north and what is the south pole of magnetic fields of stars and black holes?

The question is related to this about Are there collected data about the direction of rotation of black holes and the direction of the magnetic field?. Perhaps it is observable for pulsars?
1
vote
2answers
39 views

Are any other planetary bodies warming up as well in the Solar System?

Do we have a few decades worth of surface temperature data to compare?
10
votes
3answers
1k views

Existence of gravitons?

For a lot of my uninformed life, I have doubted the existence of gravitons or even that gravity is an actual "force" (like electromagnetism). This is because my vision of general relativity was that ...
1
vote
1answer
55 views

What would be the outcome for life in our galaxy if the merger of the Milky Way and Andromeda creates a Quasar?

If predictions are correct, the Milky Way and Andromeda are set to collide in around 4 billion years. If, when this occurs, a Quasar is formed by matter being accreted to the common galactic center ...
1
vote
3answers
41 views

What planet is better than earth to infer solar system configuration?

The mankind had to work some centuries to infer the real configuration of solar system, starting from greeks, Ptolemeus, until Copernicus, Galilei, Kepler, Newton etc. Is there any planet where we ...
0
votes
0answers
20 views

Time travel possible? [on hold]

I once saw on television that if we focus all the light of our sun to a specific point which might create some kind of hole, than we might be able to time travel ( I don't understand how) or if we ...
1
vote
1answer
69 views

Are we so sure global warming is a result of humans burning fossil fuels? [duplicate]

The Sun is a fiery mass of colliding particles. We still know very little about what it is. Could it possibly be the output of the sun fluctuates, like our weather, from one extreme to another. ...
-1
votes
0answers
17 views

Data analysis projects fora newly renovated desktop? [on hold]

I just renovated a desktop that had been in storage for a while, and I'd like to come up with some big data analysis projects to run on it in the background. Does anyone have any ideas, know of any ...
1
vote
0answers
24 views

Are there collected data about the direction of rotation of black holes and the direction of the magnetic field?

Is there a relation between the direction of rotation of black holes or neutron stars and the magnetic dipole moment of BH or neutron stars? BTW, are there different directions of this two parameters ...
1
vote
0answers
14 views

Eclipse in sun-synchronous orbits

I am trying to figure out the eclipse periods of a satellite orbiting the Earth. The satellite is placed on a circular sun-synchronous orbit at 800 km height. The LTAN (local time of ascending node) ...
-3
votes
2answers
49 views

Large hadron collider [on hold]

Whether the collision of particle will lead to a massive WORMHOLE or if BLACKHOLE is also possible? How much I know is that it's created for einstien's E=mc^2 ,conservation of energy from mass and ...
3
votes
0answers
22 views

Orbital eccentricity variation of the other planets?

On Earth, it's fairly well published, mostly in climate change related articles, that the Earth's orbital eccentricity operates on a 413,000 year cycle with roughly 90,000 - 125,000 year variation ...
1
vote
1answer
34 views

Is it ever possible that the graviation from the mass of kinetic rotational energy will overcome centrifugal force?

This is, I think, somewhat intuitively obvious, but this comment got me thinking about this: what is gravitational force? "Rotation speed can create centrifugal force opposing gravity and making ...
6
votes
2answers
45 views

Precision of geocentric gravitational constant

I am looking for an answer as to why the geocentric gravitational constant, μ, defined as the product of the gravitational constant, G, and the mass of a body (earth in this case), M, can be ...
1
vote
1answer
18 views

Does earth's Umbra reach Sun-Earth L2?

Moon can be fully eclipsed by the virtue of being fairly close to Earth. Any body distant enough will not be eclipsed fully, Earth's disc not fully covering Sun's disc. How's that for anything at the ...
0
votes
2answers
34 views

Distance of a planet to the star?

QUESTION: Suppose we discover a planet orbiting a nearby star. The distance to the star is 3 pc. We observe the angular radius of the planet’s orbit to be 0.1 arc sec. How many AU from the star is ...

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