0
votes
0answers
3 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 ...
6
votes
1answer
197 views

What is the bluest narrow band filter mounted on ground based telescopes?

If we want to check a QSO's lyman alpha narrow band image, could a ground based telescope do that? I mean under the circumstance that its lyman alpha shifts to 3300A.
21
votes
2answers
4k views

Why does Jupiter have so many moons?

Jupiter has a great many moons - in the hundreds, and they're still being discovered. What is the current theory for where all these moons came from? Are they rocks flying through space captured by ...
7
votes
2answers
39 views

What special set of conditions would lead to this event?

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 ...
2
votes
0answers
7 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
0answers
9 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 ...
0
votes
1answer
32 views

Eclipse — Solar and Lunar

Q. Why is solar and lunar eclipse not seen from all parts of the earth at the same time? I think its because of the revolution of the earth but i am not sure. I want a more reliable answer.
1
vote
1answer
30 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 ...
1
vote
1answer
40 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 ...
0
votes
1answer
22 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?
0
votes
1answer
23 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 ...
2
votes
5answers
148 views

What is spacetime 'made' of?

General relativity is often explained as saying spacetime is curved by gravity, what does this mean? How could we perceive a curve in spacetime when there is no external "straight" reference frame for ...
1
vote
3answers
33 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 ...
1
vote
1answer
34 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?
0
votes
2answers
28 views

Is parallel universe possible

Does parallel universe really exists or just science fiction which ain't possible? Can we ever know ?
13
votes
5answers
2k views

By putting a mirror in space, would we be able to see into the past?

I only ask this because of how fast light travels. The question remains in the title. Why, or why not, would this work?
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 ...
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
10 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?
6
votes
1answer
105 views

Is it accurate to compare comets to clouds and rain?

I'm trying to avoid an opinion-based question, so before I outline the comparison I'm proposing, I will qualify the specific facts that yield this comparison. By focusing answers on the relative ...
1
vote
1answer
60 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
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?
0
votes
0answers
29 views

Did the expansion from the Big Bang propagate faster than the speed of light? [on hold]

Did the original Big Bang cause an expansion faster than the speed of light? What is the speed of the current expansion with relation to the speed of light? Is it possible for another Big Bang to ...
2
votes
1answer
48 views

Finding a location using the direction of shadow, UT and date approximately

Does anyone know how to find a location by using : the direction of shadow relative to the normal (for example azimuth angle) the Universal time (UT) and date I have a satellite image and I know ...
2
votes
1answer
31 views

Since the Universe is expanding, is it accurate to say that a galaxy is 5 billion light years away?

Isn't it better to say that the light from the galaxy took 5 billion light years to reach us and it is a very old picture of it? However, if light travelled back to the galaxy at the constant speed ...
1
vote
1answer
39 views

What happened just before the Big bang?

Does the CMB contain any clues to what caused the Big Bang? Does a mathematical model theorize it?
0
votes
2answers
25 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 ...
4
votes
3answers
400 views

How did our ancestors discover the Solar System?

I wonder, how did our ancestors discover the Solar System? They did not have any telescopes to see distant objects, right? Even a planet looks like a star from a distance. They discovered the ...
8
votes
5answers
846 views

Why do stars become red giants?

Disclaimer: I’m not a career astronomer. I don’t own a telescope. I have no professional credentials. But I do find this stuff fascinating, and I consume all the astronomy documentaries I can. ...
2
votes
2answers
423 views

How to calculate a planet's current position within the solar system

I'm making an application that needs to calculate a planet's current position within the solar system - I don't want to calculate its position in the sky. For example, what I want to do is exactly ...
0
votes
0answers
17 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 ...
6
votes
1answer
96 views

As viewed from Mars, what are Jupiter's and Saturn's maximum brightness in apparent magnitude?

From Earth, Jupiter's maximum brightness is -2.94 and Saturn's is -0.24. But what about from Mars? They should be brighter, but by how much? There are equations at the obvious wiki entry but I'm not ...
0
votes
0answers
22 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 ...
17
votes
4answers
9k views

Does the Sun belong to a constellation?

Each new star we find is generally considered to be part of the constellation it is nearest to. Our Sun is obviously a star, just much closer. Is our Sun part of any constellation? If so, which ...
0
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
13 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 ...
0
votes
1answer
136 views

How to calculate the temperature of a star

I need a way to calculate the effective temperature (surface temperature) of a star for a stellar model. I need something in the form Te=.... I have: Radius in m mass in kg the composition of ...
0
votes
0answers
51 views

highspeed black holes or neutron stars on (almost) head-on collision course and kinetic energy

First: I don't think this is a duplicate question. There are related question on mergers of black holes that orbit around each other etc., so please read on. I'm having a hard time picturing what ...
3
votes
0answers
19 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
70 views

Question about space-time

In the big bang model of the Universe, every observable thing is thought to have expanded very abruptly from a point of infinite density and zero volume. However, the problem with this assertion is ...
0
votes
1answer
96 views

what is gravitational force?

Gravitational force is particle or wave? I know that gravitation depend of the mass and the rotation speed but what is the transmission medium of this wave the same like transmission medium of the ...
6
votes
2answers
40 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 ...
0
votes
0answers
6 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 ...
1
vote
1answer
67 views

Would a satellite in geosynchronous orbit between the earth and moon track across the sky together?

On Nov. 25 at 2:30a.m. from southern California while viewing the moon with a 70mm D x 400mm F telescope a point of light was seen at about the 7 o'clock position below the moon. As viewed the point ...
1
vote
1answer
19 views

How to see other celestial things using stars for direction?

I have a simple question. I can see orion constellation clearly in the night sky. I read it somewhere on this website that gemini is on the left-hand side of orion constellation. I was able to spot ...
-6
votes
1answer
69 views

Is this Universe scenario correct? [on hold]

I will try to give you my reasoning behind my scenario. Ok I've researched and found That 95 percent of the galaxy has been formed already, And the other 5 percent is still to ...
5
votes
1answer
44 views

How does an accreting black hole acquire magnetic fields?

There is actually a similar question on this site: Can magnetism escape a black hole?, however the answers do not focus on accretion, which is my main concern, so I start a new one. In Kip Thorne's ...
0
votes
0answers
31 views

Is Planet Nine shepherding the Kuiper Belt?

Is it possible Planet Nine is shepherding the Kuiper Belt similar to the way Jupiter shepherds the asteroid belt? I understand that very little is actually known about Planet Nine at this point, but ...
1
vote
1answer
30 views

Why is it strange that outer stars are travelling with the same speed as inner while the total mass is also increasing?

Astronomers say that it's strange that the outer stars of a gallaxy are travelling with the same speed as the inner stars. Therefor they introduced dark matter to solve this strangeness. The theory ...

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