1
vote
1answer
8 views

Are satellites 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
18 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?
1
vote
1answer
16 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 ...
2
votes
1answer
13 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 ...
2
votes
0answers
11 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
47 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
24 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
25 views

Will we ever end up in the black hole?

Since we are spiraling around the black whole will we spiral into the black hole?
2
votes
3answers
201 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 ...
4
votes
1answer
33 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
51 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
23 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 ...
1
vote
1answer
47 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 ...
2
votes
0answers
15 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
47 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 ...
5
votes
4answers
55 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
67 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 in the process of ionization,recombination,ionization,recombination.... ...
3
votes
1answer
58 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
15 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 ...
0
votes
0answers
18 views

Time Travel by means of 1) Gravitational Lensing and 2) Extreme Speeds [closed]

Two known methods of time travel are gravitational lensing and extreme speeds. Neither can currently be exploited for a significant human jump in time, but is it likely that humans will ever be able ...
4
votes
2answers
44 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 ...
3
votes
1answer
29 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 live in Cambridge, UK and ...
0
votes
1answer
51 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
26 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 ...
0
votes
1answer
28 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
52 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
42 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
79 views

Will the UK be able to witness the tetrad in August 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
1answer
61 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
44 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 ...
1
vote
2answers
33 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
94 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
32 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 ...
2
votes
2answers
106 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 ...
2
votes
1answer
54 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
95 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
85 views

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

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
56 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
1answer
96 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
17 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
50 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 ...
4
votes
1answer
50 views

Density of hydrogen between galaxies

From watching a video on youtube, it states that Dark Matter is 6 times more abundant than known matter. I was wondering if it was possible to have hydrogen clouds between the universes galaxies. The ...
1
vote
1answer
101 views

How big is the universe. How does it works?

I watch this movie: How big is the universe https://www.youtube.com/watch?v=b34gwCKIM50#t=50m00s I can't understand where is there triangle with 180 degrees. What exactly is this red spot on the ...
3
votes
1answer
67 views

Is it possible neutron stars are actual elements?

As you go up the periodic table (more protons), the ratio of neutrons to protons steadily increases as well. Are we sure there are absolutely no protons and electrons in a neutron star, or could there ...
1
vote
0answers
36 views

Does NASA have a plan to search for the life in Europa? [migrated]

Europa is one of the most interesting moons in our solar system. It seems possible that some kind of living beings are able to live beneath its frozen surface. Question. Does NASA (or any other ...
3
votes
1answer
77 views

Collision of 2 black holes

There is a large number of visible Supernovas. Each week - about a 20 Supernovas Type 1a around the Universe. Is there collisions of Black Holes? What is this collision called? E.g. 2 black holes ...
2
votes
0answers
18 views

Exoplanet naming conventions

I'm looking for any exoplanet nomenclature, official, semi-official, proposed, or just a good idea, beyond what can already be found on Wikipedia at ...
6
votes
1answer
182 views

Layout of the universe

I've been working on a space game in my spare time, and lately I've been thinking on how to layout the universe. Though I searched around and found it hard to get a good view of what the universe ...
1
vote
2answers
58 views

How would water waves behave in partial gravity?

Would an "indoor" pool of water on the Moon or on Mars behave differently than on Earth? Would the waves caused by a splash be higher or lower? Would they propagate faster or slower? Would boyance be ...
1
vote
2answers
95 views

Why is there a daily inequality for low tides?

I understand why there is a daily inequality for high tides. What I do not understand is why the low tides are not equal. The data all seems to be somewhere along the lines of but the theory seems to ...

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