2
votes
4answers
223 views

Why can't I see Mars clearly?

I just bought my first telescope - a Celestron CDC 1100. It came with a 40mm lens so with a primary focal length of 2800mm the power should be 70x. My problem is that I've looked at Sirius and Mars ...
6
votes
2answers
333 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?
1
vote
2answers
28 views

Convert orbital elements to positions and velocities

I've written a quick and dirty n-body simulator, but currently it requires initial positions and velocities. I've been looking for a way to convert Keplerian orbital elements to positions and ...
2
votes
1answer
45 views

How do I calculate the velocity dispersion of a galaxy given an integral field spectrograph?

I couldn't find on the web how to get the velocity dispersion and velocity maps of galaxies from the 3D data cube that I get from the integral field spectrograph.
9
votes
5answers
2k views

What will happen to life on Earth when Andromeda and Milky Way galaxies collide?

It is said that, Andromeda and Milky way galaxies are coming close to each other with the speed of approx 400000 km/hours. They will be together in the next 4 billion years. 1> What will happen to ...
1
vote
2answers
357 views

Is it possible to create an artificial Black Hole?

I am quite curious about black holes. Once I just thought whether it is possible to create an artificial Black Hole, i.e. an human made black hole. Also explain there formation if it is possible.
12
votes
2answers
762 views

How many planetary systems exist in our galaxy?

For many years scientists have studied our own solar system and modern technology allows them to look deeper and deeper into space. Knowing the Sun is only one of a few billion stars in the Milky Way ...
2
votes
4answers
131 views

What is the speed of light relative to (in space)?

From what I understand the universe is expanding faster than the speed of light and accelerating so that it's possible that a given galaxy: $A$ will no longer be visible to another given galaxy: $B$. ...
0
votes
1answer
61 views

star atlas with absolute magnitude and spectral type

Is there any star atlas someone recommends? Then for some kind of star with a definite spectral type, we can know its absolute magnitude.
-1
votes
2answers
65 views

Earth's gravitational pull on ISS

How do they make International space station to orbit the earth beyond earth's gravity acting on it? We all know that ISS is rotating at an altitude of just 350km away.How could ISS escape earth's ...
0
votes
1answer
101 views

The reason behind Big Bang

It always amuse us to research about things around us and we always start our research with a question that - what must be the reason for happening of that phenomenon? As we know that the formation ...
1
vote
1answer
81 views

Is it possible to extend the life of a star?

Is it true that when a star 'runs out' of its fuel, it hasn't really used up all its hydrogen, it still has hydrogen left, but the hydrogen is not at its center where the fusion happens. If something ...
1
vote
1answer
38 views

Question about the formation of elements

So, elements such as iron, gold, etc. are formed from different types of supernovas, whether it's type 1A or 2. My question is, is it possible that there are elements that are formed that we never ...
1
vote
1answer
43 views

Average rate of supernova x number of stars

If we would take the average number of supernovae per year and multiply that by the number of stars, could we figure out how many years it will be before all stars are gone?
2
votes
1answer
53 views

Apogalacticon and Perigalacticon

What is the length of the apogalacticon and perigalacticon of the Sun and Milky Way? The general terms seem to be apoapsis and periapsis. My greatest efforts at Googling have failed miserably. If ...
3
votes
1answer
61 views

Why is a meteorite impact on the moon visible as white light?

You can watch a video of a meteorite impacting the moon at the npr.org website. Why does the impact produce white light? I understand that the impact is like an explosion, but there is no air on ...
1
vote
3answers
52 views

State of the stars

This question may sound silly but I'm really not pretty sure whether the stars are rotating or stationary.If they are not rotating what makes them to be stable?
1
vote
1answer
28 views

Do more objects appear on sky in time?

I would assume that, with light from more distant areas in space reaching the earth, we should be able to see more distant (and older) objects. However there's lot of weird stuff regarding the space ...
3
votes
1answer
114 views

Do telescopes harm while observing sun through them?

I don't know whether we can observe a sun through a telescope. But if we can then will it harm our eyes and if such telescopes exists what is their configuration?
2
votes
1answer
32 views

Sattelite's orbit

What is the maximum distance for a satellite to orbit the earth? Does earth's gravity has the impact on satellite? I do know that earth's gravity will never be zero and it's gravity is inversely ...
1
vote
1answer
94 views

When did the Moon stop?

According to various theories the Moon was created around 4.5 billion years ago. About all of these theories suggest that it was rotating around its axis at that time though. Currently, Moon is at ...
2
votes
2answers
23 views

Locate asteroid in asteroid belt

I was interested in tracking the orbit of 1986 DA. I couldn't find any resource when I looked. Just for fun, so any help appreciated.
0
votes
3answers
82 views

How fast is the universe expanding?

I've hear several theories stating that the universe is expanding faster than the speed of light, others claim that the universe expands faster the further away you measure it. Which of this is ...
1
vote
1answer
25 views

Do meteorites streak across the sky in the same direction?

Once while camping with my family as a child we all watched a meteor shower in the summer (in the month of August). All the meteorites streaked across the sky in the same direction. Obviously, this ...
2
votes
1answer
118 views

Can an amateur astronomer bounce a laser off the moon?

In the TV show "Big Bang Theory" episode "The Lunar Excitation", the gang fires a laser from their rooftop, bounces it off mirrors on the moon, and measures the laser coming back on a computer. Is ...
7
votes
3answers
126 views

Why is the interstellar medium so hot?

On this link, it states the following: "large assemblies of galaxies that are permeated by even larger amounts of diffuse gas. With temperatures of 10 million degrees or more". How are these ...
5
votes
1answer
116 views

From which country or area is the new moon visible first?

Being able to see the Moon is dependant on various factors like sunset timing etc. Considering all these factors, which country or area of the world sees the new moon first? I am asking about the new ...
3
votes
1answer
62 views

Do planetary surface temperatures change in unison in a solar system?

Are there any known correlations between the changes in planetary surface temperatures in a solar system? If so, do the farthest planets have smaller albeit correlated changes?
2
votes
2answers
102 views

What is Event Horizon of a Black Hole? [closed]

The boundary of a black hole is said to be surrounded by event horizon - the point of no return! What is its significance in terms of general relativity?
1
vote
0answers
45 views

How to get the longitude/latitude from solar zenith/azimuth?

How do I get the longitude/latitude from zenith/azimuth? Or how can I position my sun in a 3d application? code extracted from here ...
2
votes
2answers
50 views

How close would quasars have been to each other?

My understanding is that quasars are the early phase of formation of galaxies. At the time quasars were forming, the universe would have been smaller and therefore things closer to each other. About ...
1
vote
2answers
122 views

Age of the universe

A Galactic year is estimated to be around 250 million "terrestrial" years. That means there will be about 4 rotations per billion years. And age of the universe is estimated to be near 13.8 billion ...
4
votes
1answer
70 views

How far apart can two people watch the moon simultaneously?

Obviously there's a limited part of earths surface where the moon is visible at any given time. I imagine the area of this surface would be a lot smaller than the area where the sun is visible at any ...
2
votes
1answer
76 views

How can I calculate the orbital periods in a binary star system?

I have two stars, with known masses and known orbital radius. How do I calculate the orbital periods of both stars?
4
votes
2answers
76 views

Why does e.g. Hubble's secondary mirror not block part of the picture?

The SOHO observatory has an opaque object in the light path that blocks the direct light from the sun making it possible to observe the corona. Hubble and many other telescopes have a big primary ...
4
votes
1answer
112 views

What is the maximum number of planets in the habitable zone?

At present, it seems like we are alone in our solar system. How many earth-like planets would fit into the habitable zone of the solar system? The orbits should be stable for quite a time, i.e. for ...
2
votes
1answer
56 views

How would light from a blue or red star affect the way we see?

How would things look if we saw them through the light of a blue or red star? Would there be any changes?
1
vote
1answer
66 views

If we lived in a multiverse, what would our universe most likely then be named? [closed]

For instance, we live in the Milky Way Galaxy. We don't just call it "The Galaxy", because we know there are multiple different galaxies. So if we lived in a multiverse, it wouldn't make much sense to ...
6
votes
2answers
100 views

Can the supernova remnant SN 1572 be observed by amateur astronomers?

The SN 1572 remnant, also called Tycho's supernova remnant, is beautiful in X-ray images. It seems to be rather dim in visible light. Are there any amateur photographs of this object? How long are the ...
12
votes
4answers
535 views

Is the light we see from stars extremely old?

Our nearest star Proxima Centauri is 4.243 light years away from Earth. Does that mean we are seeing light that is 4.243 years old everyday?
6
votes
2answers
51 views

Are we moving ever closer to the center of our Galaxy due to a super massive black hole?

I've seen in documentaries that at the center of each galaxy is a super massive black hole which holds the galaxy together. Since black holes have such a strong pull, are we slowly being pulled in ...
1
vote
1answer
76 views

Black Hole, Object or Portal? [closed]

Some say that a black hole is a rip in space-time, a portal linking two points in the universe as one. How sound is this? I've read that when a giant star collapses, what is left behind (a massive ...
2
votes
2answers
53 views

Can looking at the sun through solar viewing eclipse shades everyday harm your eyes?

I have a pair of Solar Viewing Eclipse Shades that say "Safe for Direct Solar Viewing" and would like to know if my eyes would be harmed if I looked at the sun everyday for about a minute wearing ...
4
votes
1answer
70 views

Why does the darkening of the Moon go from left-to-right during an eclipse?

In anticipation of the upcoming April 2014 lunar eclipse, I decided to use the 3D virtual planetarium software Stellarium to simulate what it is supposed look like where I live, since I've never ...
2
votes
1answer
35 views

What happens to the shrinking universe in the presence of the pressure of Hawking radiation?

Black holes release Hawking radiation. Now assume that the universe after all collapses back again, bringing all matter to a single black hole. I assume that this would bend the whole space-time of ...
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
49 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 ...

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