0
votes
2answers
184 views

How can the universe be infinite?

I've heard from renowned astrophysicists that we don't yet know whether or not the Universe is infinite. How is that possible regarding the big bang theory is accepted (as they all do)? Are they ...
6
votes
3answers
244 views

What is a singularity? What is at the center of a black hole? Specifically regarding space-time

So because I can only really think of space-time in 2-dimensions like a sheet of something, my assumptions might be wrong to begin with. I was watching a YouTube video on black-holes and there was a ...
3
votes
2answers
88 views

Why is Mars considered the outer edge of the “goldilocks zone”?

In both books and documentaries I often see the Goldilocks Zone as described between Venus and Mars with the Earth "just right." This seems sort of ill thought out to me, because it assumes that ...
4
votes
2answers
119 views

Does the earth's atmosphere act as a spherical lens and refract light from space?

If so by how much does it "spoil" the view of stars and galaxies etc. Is this error noticable, when compared to pictures taken from outer space.
1
vote
3answers
182 views

Why is iron responsible for causing a supernova?

Why is the element iron responsible for supernova? Can any star create more element than iron within the span of its life? I understand that when star dies due to supernova, other elements are ...
4
votes
1answer
102 views

Maximum Amplitude of a Lissajous Orbiting Object in a L4 or L5 Position

I stumbled on The Lagrangian points during some wikipedia reading. After looking at the gravity contours, I naturally come to the conclusion that the L4 & L5 should have a wave pattern and then ...
6
votes
1answer
385 views

Why is the solar system often shown as a 2D plane?

Whenever I have learned about the solar system I always see the orbits displayed as a virtually flat plane. Are all of the orbits in the solar system really like this? If so, why? It seems like a ...
1
vote
1answer
117 views

Please Guide me to buy my first Telescope [duplicate]

I am a beginner and I've planned to buy a telescope(Newtonian reflector)for viewing planets and deep sky objects. As far as I know the most important factor to get a brighter view is that the ...
3
votes
2answers
113 views

What is the term for a star swallowing another star?

A star A goes through the body of another star B, or is swallowed by B. There is no tidal disruption. It sounds like kerzan. Does anybody recognise this pronunciation?
2
votes
1answer
192 views

Black Hole / Hawking Radiation: Why only capture anti-particle?

I may have some specifics wrong here. If so, don't focus on those. Just focus on the general thrust of my question. I "understand" (cough) that particle/anti-particle pairs form spontaneously in ...
7
votes
1answer
1k views

Are satellites orbiting around earth visible to the naked eye?

I was just lying under the sky trying to possibly see some meteorites, unfortunately never seeing any I might add, but I saw three objects all moving at about the same speed( all at different times). ...
2
votes
1answer
64 views

Choosing a diffraction grating

I am interested in doing some solar spectroscopy on my own for fun. How do I go about choosing the appropriate diffraction grating?
3
votes
2answers
100 views

Questions about time and space (from beginner)

To be honest my knowledge about astronomy and related physics is close to zero. However, since I studied math a bit, I would like to ask a couple maybe stupid questions, which I am curious about and I ...
3
votes
1answer
112 views

Which type of telescope should I make?

I am not very much interested in observational physics but I just like to look at the night sky. It gives me a lot of inspiration. So, i was thinking about making a telescope for basic observations. I ...
3
votes
1answer
62 views

How to use a telescope to find a specific celestial body?

I am a beginner interested in astronomy. I bought a Celestron AstroMaster 130EQ telescope. It's a Newtonian Reflector and it's not computerised. I did manage to see the Moon in some magnifications but ...
3
votes
2answers
91 views

How and when did we learn about the universe?

I'm 13 - I'd like to know how we found/discovered important details about the Universe. I know we have found many different things about the Universe, but when did we find how amazingly large the ...
1
vote
2answers
60 views

How are East and West defined on other bodies of our solar system?

I noticed that East and West appear swapped on maps of the Sun, even though the Sun rotates around its polar axis in the same sense as Earth. See for example below Sun disk with a Venus transit ...
1
vote
1answer
48 views

Will we ever end up in the black hole? [duplicate]

Since we are spiraling around the black whole will we spiral into the black hole?
2
votes
3answers
287 views

First night on a telescope questions

So I recently got into astronomy and I am using my fathers old Meade EQ1-B reflector telescope. This is my first night using it and I have come across a few questions. To begin, the telescope was left ...
5
votes
1answer
72 views

What was the age of the universe when the average density was one atmosphere?

How long did it take after the Big Bang for the average density of the universe to reach one Earth atmosphere at sea level? How about the density of water? Is there a chart of densities that relate to ...
5
votes
1answer
591 views

Best telescope for the viewing of Nebulae, Stars and Planets

So, I am a 15 year old interested into astronomy. My father used to have a reflector telescope, but was never so serious about it that he could recommend me a good telescope. I am looking to buy a ...
1
vote
1answer
32 views

Assumption of our universe being the surface of a 4-D sphere in order to describe relative uniformity in the cosmic microwave background?

It seems as if this is necessary to assume in order for the CMB to make an sense. Otherwise, an instantaneous infinite Euclidean space model would work. The issue is, with any visualization of the Big ...
3
votes
2answers
111 views

Stellar mass of galaxies

Given the magnitudes (in the i-band) of certain galaxies, I would like to calculate their stellar mass (in terms of solar masses). So far, I have calculated their absolute magnitudes and gotten to ...
3
votes
3answers
94 views

Are there standard algorithms and procedures for creating unique sky maps based on latitude/longitude/date/time?

I am trying to build an astronomy app that will use the user's latitude and longitude, along with the current date and time, to create a 3D view of the celestial sphere as seen based on that data. ...
2
votes
1answer
79 views

Inability of Hubble to clearly resolve nearby celestial objects

The Hubble space telescope performs incredibly detailed and stunning imaging of celestial bodies that are many, many light years away, and yet when it attempts to image objects within our own Solar ...
7
votes
4answers
186 views

What will a lunar eclipse look like from moon?

What will a lunar eclipse look like from moon? Will earth become a completely dark circle?
1
vote
3answers
230 views

The formation of absorption lines in solar spectrum

It is said that absorption lines originate from regions higher in the photosphere where the gas is cooler. The gas should be absorbing photons, then re-emitting them... absorb, re-emit, absorb, ...
5
votes
2answers
350 views

Our universe the surface of a 4-dimensional sphere?

The cosmic microwave background that we observe uniformly around us is usually explained by assuming that our universe is the surface of a four dimensional sphere. That way the uniformity makes sense ...
0
votes
1answer
17 views

First meteor(s) of Lyrid meteor shower?

So I am a newcomer to Astronomy - only aged 15 - and am currently looking upon the sky in hopes of witnessing several meteors. This is my first time ever - maybe - seeing them. I just went inside for ...
5
votes
3answers
118 views

Red Moon a Characteristic of all Total Lunar Eclipses?

I understand that the redness of the moon during the total lunar eclipse last night/this morning (April 14-15 2014) is a reflection of the red light caused in earth's atmosphere due to Rayleigh ...
4
votes
1answer
47 views

Where will I be able to see the Lyrid meteor shower?

So supposedly the Lyrids meteor shower will take place between early morning April 16th to 22nd - correct me if I am wrong. I am aged 15 and am interested in skywatching, I just wondered will it be ...
1
vote
1answer
85 views

Finding a Kerr Black Holes

I understand that Kerr Black Holes are purely theoretical and have not been found anywhere in the Universe. However, they are theorized for possible means of time travel. I am attempting to prove in ...
0
votes
1answer
36 views

Cosmic microwave background radiation

If the big bang is true, after the emission of light from the hydrogen plasma, the universe was still expanding. Why would we expect to see uniform radiation if earth very well could have formed ...
1
vote
1answer
2k views

Why is the Solar Helical (Vortex) model wrong?

Could someone give a lay description of why the Solar System's depiction of motion as a vortex is wrong? ref: Youtube video The helical model - our solar system is a vortex Please don't take for ...
4
votes
1answer
84 views

How did Copernicus get the idea of heliocentric model?

The heliocentric model marked the beginning of modern astronomy. But what were the reasons which led Copernicus to think that the earth orbited the sun. I've read that his model was based on ...
3
votes
1answer
60 views

Movement of the satellites of the planets . . .

Is the movement of the satellites (moons) of a planet coplanar, like the planets being coplanar around the local Sun?
4
votes
1answer
104 views

Will the UK be able to witness the tetrad in April 2014?

I live in the UK and am aged 15. I have become extremely interested in astronomy, astrophysics, the lot. Basically I have never seen a tetrad and believe this will be my first time - at least ...
2
votes
2answers
100 views

Conundrum involving distance to object, universal expansion, age of universe, etc

I was recently reading about a galaxy or quasar (not sure which, so lets just say quasar) where the estimated distance to this thing was some very significant fraction of the age of the universe. ...
1
vote
1answer
93 views

Position and velocity vectors of nearby stars?

One of my favorite tools for modeling the solar system is the Horizons Ephemeris generator where I can get position and velocity vectors of various bodies. Is there something similar for neighboring ...
2
votes
2answers
84 views

Satellite/Planetary Orbits

All planetary orbits contain 5 unusually stable points. These points are particularly important because they allow man-made satellites to orbit the Sun with a period equal to that of Earth’s. 3 of ...
4
votes
2answers
163 views

Why don't planets and asteroids have (cometary) tails?

Comets have tails. We all know that, and a lucky few have seen the better known. So why don't the planets (e.g. Earth, Mars) have tails? Why don't asteroids don't have tails?
2
votes
1answer
43 views

Why do Jovian moons fade when transiting Jupiter's shadow?

When reading an article on using Jovian moons to calculate longitude, I came across this passage: Periodically, Jupiter eclipses each of the four large moons as they pass into the planet's mammoth ...
3
votes
2answers
283 views

What is the name of that which exists beyond the Universe?

"The Universe is commonly defined as the totality of existence" but that is more of a philosophical position. Empirically we know (or believe) that it is of finite size some believe it is expanding ...
4
votes
2answers
130 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.
6
votes
2answers
172 views

Is there any difference between parallel universes and multiverse?

Nowadays we come across with these two terms - parallel universes and multiverse. I wonder if this is the same thing or its two entirely different principles because the names are a bit confusing to ...
5
votes
1answer
117 views

Might the universe be really small yet seem infinite from spherical reflections? [closed]

if a single source of light quite small, was placed somewhere inside a completely reflective sphere, quite large, what would the reflections look like from the light source's point of view within that ...
2
votes
1answer
82 views

Einstein General relativity and bending of space [closed]

As Einstein's General relativity suggests that the space time curves in the presence of matter, which is experimentally proven too, this phenomenon also explains orbits. My question is if the ...
2
votes
2answers
549 views

What would happen if Jupiter and Earth were at the same distance as the Moon is from Earth?

If Spock came with a super machine capable of moving planets, and placed Earth so close to Jupiter as the Earth's moon, the gravity of Jupiter would make us fall into it?
1
vote
1answer
30 views

Telescope in Sun's gravity lens focus - pointing, gain, distortions

A telescope located in the gravitational focus of the Sun can use the Sun as a magnifying lens. The focus begins 550 AU away, but maybe a 700 or 1000 AU distance is needed to get rid of disturbances ...
2
votes
1answer
102 views

“How the Universe Works”: is it scientifically accurate? [closed]

The documentary/mini-series How the Universe Works is based on scientific evidence and according to what is known nowadays, or sheer bunk? Throughout the series, are there any particular topics which ...

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