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
123 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
48 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
91 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
38 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
91 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
61 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
105 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
104 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
99 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
175 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
44 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
312 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
142 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.
7
votes
2answers
178 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
121 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
703 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
32 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
111 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
55 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
238 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 ...
5
votes
2answers
121 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 ...
4
votes
1answer
157 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 ...
5
votes
1answer
79 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 ...
9
votes
1answer
384 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 lay out the universe. Though I've searched around and found it hard to get a good view of what the universe ...
1
vote
2answers
123 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 ...
2
votes
1answer
201 views

What is the minimum mass required so that objects become spherical due to its own gravity?

Is this minimum mass known? or maybe, is it given in terms of density? If so, how much density is the minimum to have an spherical object due to its own gravity?
2
votes
2answers
48 views

What is meant by Electronic Beam Steering and how is it achieved?

I recently came across an article about the Murchison Wide Field Array which said directivity is achieved by Electronic Beam Steering and not by Mechanical methods. It would be helpful if someone can ...
7
votes
2answers
76 views

Present distances between planet. How can I find them?

It's "commonly known" how distant are our solar system planets from Sun. But we can't easily say that about planets, which distances can differ greatly, without some observations (or simulations, ...
3
votes
2answers
144 views

What's the furthest object observable by the naked eye from earth?

From XKCD: Caption: 'The light from those millions of stars you see is probably many thousands of years old' is a rare example of laypeople substantially OVERestimating astronomical numbers. So, ...
5
votes
1answer
112 views

Can a black hole reach a limit where it can no longer attract more matter?

Can a black hole reach a limit where it can no longer attract more matter? If so, what happens with that black hole? Does the black hole die? Does the black hole decrease its size?
1
vote
1answer
114 views

Why is every year the same number of days despite the gravity in the solar system?

I was just watching a Geoff Marcy talk on YouTube showing how they infer the presence of planets transiting distant stars. The supposed periodicity wasn't always quite regular from what I could see, ...
1
vote
1answer
98 views

3D Positions of Nearby Stars

I have come across a number of star catalogs that list stars by right ascension and declination, along with other data such as magnitude. Is there a star catalog that lists the 3-D position of stars ...
3
votes
1answer
123 views

What’s the object between the earth and the sun currently showing in Google maps?

If I select satellite imagery in Google maps and zoom out, the earth is shown in space. It shows light/dark regions correctly updated, but there’s an object between the earth and the sun. It looks too ...
4
votes
1answer
121 views

Build a high quality telescope from scratch [closed]

I am interested in building a high quality portable telescope from scratch in an attempt to better understand how telescopes work. What kind of materials do I need? How would I go about putting the ...
1
vote
1answer
56 views

What is the connection between moons, rings, and gaps?

I was watching this video and they said that the rock probably has a moon. Is the reason they assume it has a moon is because there is a gap between the rings created by the moon's orbit around the ...
7
votes
1answer
311 views

Is it possible that all dark matter is made of rogue planets (free-floating planet)?

Is it possible that all dark matter is made of rogue planets (free-floating planet)? (and other stuff like asteroids or meteoroids)
0
votes
1answer
107 views

Does the holographic principle contradict eternal inflation?

As it is for example explained here, Andrei Linde's chaotic inflation is among the potential winners or survivors of the spring cleaning induced by the potential detection of primoridal gravitational ...
1
vote
2answers
117 views

How did Bradley arrive at the +/- correct speed of light when he calculated it?

After Bradley discovered stellar aberration and the corresponding constant of aberration he was able to calculate the speed of light, since he knew the speed of the Earth around the Sun. As far as I ...
3
votes
1answer
52 views

Space objects visible from earth

I recently saw the International Space Station without a telescope. Are there any other man-made space objects that can be seen using bare eyes?
1
vote
0answers
149 views

How can I calculate what star was above my head when I was born? [closed]

Almost everybody knows the concept of Zodiac. But there are others. And, AFAIK, even Zodiac classification is wrong for nowadays - since the classification of the people's Zodiac Sign was developed ...
1
vote
1answer
89 views

A curious relationship between lunar periods and the solar year

Earlier today I was exploring the astronomy features on WolframAlpha, when I stumbled upon an intriguing numerical relationship involving the values for the lunar synodic and sidereal months. Using ...
13
votes
1answer
201 views

How exactly does inflation convert random gravity fluctuations into coherent gravitational waves?

In the course of this very enjoyable press announcement, it is mentioned that inflation can create gravity waves by amplifying gravity fluctuations. I do not properly understand this statement. I ...
1
vote
1answer
91 views

Why isn't the dark energy getting decreased?

AS the articles on the web suggest, Dark energy is the reason behind the expansion of universe. If so, why isn't it getting used up in doing so. And consequently, the rate of expansion should reduce! ...
2
votes
2answers
82 views

How do scientists know if an Earth-like planet is really Earth-like?

I'm not sure how scientists determine that a planet is really an Earth-like planet. How do they do it?
1
vote
2answers
61 views

How would an exoplanet be found from earth if our view of its star system is “from the top”?

When we find an exoplanet by observing the dimming of its parent star, this means that the planet passes in front of the star from our view. What if our view of a star system is from its "top" or ...
2
votes
1answer
111 views

why are galaxies different in color?

whether its in movies,television,real-life or some planetarium different galaxies are shown in different color. For ex:- Milky way is always seen in Blue where as Andromeda gives out a bit reddish ...

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