4
votes
1answer
101 views

How did pre-Earth's mass and orbit change at the Moon formation event?

The popular, but still disputable, Moon formation theory is that a pre-Earth was hit by a Mars sized planet. The mass ratio of Earth:Mars:Moon is roughly 100:10:1. Does this mean that pre-Earth was ...
1
vote
0answers
18 views

What is the detector size of LANDSAT 8's detector array?

According to the suggested tags, this must be the right forum: I found that for each band of Landsat 8 over 7000 detectors are on the array. Does anyone know how big each of the sensors is?
1
vote
1answer
29 views

Is Polar Lights observation possible at the latitude of 56° N?

Back in 2002, me and my friends observed a green glow in the sky at night in the form of giant slow moving spurts of flame, looking more dense near the horizon and more blurred at height. It was ...
0
votes
1answer
54 views

Correlation of planet sizes with star sizes?

I did my own amateur Kepler data analysis in May of this year of data from Kepler.nasa.gov/Mission/ discoveries. I found a strong correlation between star size and planet size (percentages). 37 of the ...
1
vote
0answers
37 views

Classification of Planets?

The data from Kepler has taught us that there is a much larger number of "Neptune-class" planets out there than we previously thought. I wonder, however, if this "dominance" of Neptunes is because of ...
2
votes
1answer
40 views

Reason for a correlation between Hot Jupiters and higher metallicity in Kepler data

This question is from an amateur data analysis I did in May of data from Kepler.nasa.gov/Mission/discoveries. There were 80 Jupiter size planets in the Kepler "confirmed" planet table on this website ...
2
votes
0answers
50 views

Unbelievably high masses/ densities in nasa website data

In May, I did my own amateur analysis of Kepler data that was supplied on Kepler.nasa.gov/Mission/discoveries. This was a table of all confirmed "Kepler planets" to date (April 1, 2015). This table ...
2
votes
1answer
74 views

The largest discrepancy in the history of science

I watched a cosmology lecture given by Leonard Susskind that convinced me to put my money on dark energy being a pressure caused by energy that is evenly distributed throughout the "vacuum" of space. ...
0
votes
2answers
47 views

Could we estimate the age of the universe based on the planar property of the Solar System?

The Big Bang scattered planets and stars everywhere in three dimensions. But after billion years of moving and interacting with each others through gravity, planets moved on the same plane. Given ...
1
vote
0answers
47 views

Planets within 10 parsecs

I have been researching what we know, so far, about planetary systems within 10 parsecs. It is easy to find out what has been found, but much harder to find out what has been eliminated (for instance: ...
2
votes
4answers
147 views

Is it just coincidence that the Moon follows the ecliptic?

Or has it been gravitationally steered that way because of how it was formed?
0
votes
1answer
84 views

Can Pluto and Neptune collide anytime in future? [duplicate]

We know that, the orbit of pluto ambiguously cuts the orbit of Neptune. I want to know, whether the revolving speed of Neptune is equal to the revolving speed of pluto. If not, is there a possibility ...
2
votes
0answers
22 views

Online wide-field star cameras?

Where can I find a large list of online star cameras with wide fields of view? http://www.itelescope.net/all-sky-cameras is one example, but the images are fairly low resolution and there aren't many ...
2
votes
3answers
90 views

infinite Universe [duplicate]

I was watching a documentary and they said that Cosmologists have determined that the Universe is infinite. I find this to contradict the expansion theory. If the Universe had a starting point then ...
1
vote
1answer
41 views

How to get error out of astropy constants

How do I get the error value out of an astropy.constants quantity? ...
8
votes
3answers
197 views

Perceiving movement of stars

Are there any stars visible to the naked eye whose position, over a normal human lifetime, can be seen to have changed (relative to other stars in the vicinity)?
3
votes
1answer
133 views

What does the orbit of multiple star systems look like?

How can I find simulations of trinary, 4-nary.. etc. star systems? What do they look like? For example the Alpha Centauri system has 3 stars and possible planets. What does that orbit look like? I ...
1
vote
1answer
22 views

accretion discs in h/lmxbs

High mass x-ray binaries necessarily accrete via wind, no disc accretion? What makes the difference between a hmxb and a lmxb? In what kind of circumstances does an accretion disc form? How does it ...
3
votes
1answer
87 views

The colour of saturn as it appears to the naked eye

I have started to watch the skies in order to learn stars, constellations planets etc. The few references I checked state that Saturn presents itself to the naked eye as a pale yellow tiny little ...
3
votes
2answers
85 views

How to interpret this old degree notation?

I'm trying to follow the calculations in this paper on page 5 (see image below). The paper is describing traditional methods of calculation for a luni-solar calendar. The math is not hard, but I ...
2
votes
1answer
172 views

Venus presents same face toward Earth at closest approach. What do you make of that?

Is reference 6 in this Wikipedia article "dubious" and this passage in need of excising or clarifying? Venus's 583.92-day interval between successive close approaches to Earth is equal to 5.001444 ...
3
votes
2answers
57 views

Are micrometeorites cosmic dust?

Are micrometeorites just dust grains at high relative speed, or is there some difference between them and cosmic or interstellar or solar nebula dust? Dust as in the clouds which obscure parts of the ...
0
votes
1answer
79 views

Do bigger telescopes equal better results?

There are many large reflecting/optical telescopes around the world, just to name a few: the Very Large Telescope, Large Zenith Telescope, and European Extremely Large Telescope. My question is does ...
2
votes
1answer
72 views

Travelling at light speed(inside water) [closed]

It is a said fact that 299792458 m/s is the speed limit,nothing can go faster than this speed, or it will take an infinite amount of energy for propulsion.What we perforce in vacuum is one thing.Can ...
3
votes
1answer
101 views

What do we know about the characteristics of stellar objects, 13,3 billion light years away from us?

To receive light from objects like MACS0647-JD, I suppose, it has to has extraordinary dimensions and intensity of electromagnetic radiation. What are the mass, the dimensions and other ...
2
votes
4answers
96 views

If I were to point into the sky, how many galaxies would be in this line?

If I point in the sky and draw a line from the tip of my finger to the end of the universe, how many galaxies would this line cross? I had a discussion with my dad and he said due to the universe ...
4
votes
1answer
353 views

Why Earth does not have rings?

Why does the Earth not have rings like Saturn or Uranus?
1
vote
1answer
35 views

Amount of EM radiation (and particles) Earth “receives” from other planets in our solar system?

Can it be (or has it been already?) measured how much and what kind of EM radiation (apart from visible light)/particles Earth "receives" from a specific planet in our solar system? Can other planets ...
3
votes
1answer
101 views

Supermoon Lunar Eclipse?

I recently read this article: http://www.cbsnews.com/news/supermoon-lunar-eclipse-coming-this-month/ I'm having some trouble understanding how a "supermoon" lunar eclipse is possible. Judging from ...
4
votes
1answer
136 views

Does the universe expand at the same rate everywhere in the universe?

Specifically, I am wondering if some areas of the universe expand faster than other areas and whether the faster expanding areas diffuse the expansion through the slower expanding areas or does the ...
4
votes
1answer
109 views

Determining North-South Line Via Watch Method: Theory & Reason

I recently read that if you're in the northern hemisphere and have an analog watch, then you can point the hour hand at the sun and know that a south line lies between (bisection) the hour hand and ...
4
votes
2answers
81 views

When a neutron star accretes matter, will its mass increase?

When a nova gets matter, the outcome is that it may lose more matter because of eruptions. Only some kind of nova's masses can increase stably. A white dwarf may become a supernova after it exceeds ...
2
votes
1answer
283 views

What are iron stars?

I have a question about iron stars. I was fascinated about the theory about the inability of protons to decay, and it led me to a point where I read something about some special kind of star called an ...
2
votes
1answer
102 views

Spicules vs Prominences/filaments

What is the difference between spicules and prominences/filaments. I know that they are both in the chromosphere, and I know the difference between provinces and filaments (depends on the view), but ...
5
votes
1answer
572 views

Astrophotography - Unable to achieve focus with current setup

I am new to astrophotography and am looking for guidance. I have the following equipment: Orion StarBlast 9814 4.5" Altazimuth Reflector Tabletop telescope 1.25in Telescope Adapter Extension Tube T ...
2
votes
1answer
94 views

Roll, Pitch and Yaw of Orbital Planes

I have been reading about celestial mechanics and particularly about planetary orbits. I understand that a planet's orbit can be tilted (pitched) with respect to the Earth's ecliptic and that it might ...
1
vote
1answer
57 views

Finding the suns position in the sky anywhere at any time

What am I looking for? from any point Latitude, Longitude and date D I want to know where the sun is in the sky at any given time anywhere on our planet. I even don't know what the outcome will be ...
4
votes
1answer
102 views

Were parts of the Universe deflating during Inflation?

I was reading about the history of the early universe in Carroll & Ostlie and specifically looking at Inflation, which, as I understand, occurred because our [observable] part of the universe ...
1
vote
2answers
70 views

Real-time position of a distant celestial body

How might it be possible to determine (via some specific online empemeris or via some well-understood algorithm) the observed position of some distant celestial body (e.g. Betelgeuse)? To be ...
-2
votes
1answer
97 views

What if the earth stopped rotating and revolving at the same time? [closed]

What will happen to us are we going to move in a tangential direction with earth axis of rotation ?
1
vote
1answer
86 views

What is a Seyfert galaxy?

I know Seyfert galaxies are types of active galaxies, but I do not understand what separates them from other types of active galaxies. Are they brighter/not as bright as other types of active ...
4
votes
1answer
151 views

What causes the aurora of other planets to have different colors?

All I could come up with is it depends on the atmospheric composition of the planet as they will interact with the charged solar particles which might be true but is there is there a definite reason ...
2
votes
1answer
47 views

stellar metallicity

I saw a talk recently mentioning that another factor that may determine a star's metallicity (besides age) may be how far from the center of its "birth cluster" it is when the short lived hot central ...
3
votes
2answers
208 views

Can the Sun become a big ball of gold atoms?

The atoms inside the core of sun are continuously fusing and forming other atoms. Can this continuous fusing make gold atoms?
2
votes
1answer
233 views

The dark side of the moon [duplicate]

I encountered this statement that the dark side of the moon is hidden from our sights. Could someone please explain?
5
votes
2answers
123 views

Do most planetary systems have fewer planets than the solar system?

It is my impression that most planetary systems have, at most, three to four planets. Is that real? Or is it just that we lack the ability to detect most planets?
2
votes
1answer
74 views

Sun's apparent motion above the arctic circle during summer solstice

I'm having difficulty with an apparent contradiction about the sun's motion during the summer solstice above the arctic circle. The YouTube video The North Pole Entire Summer of never ending sun ...
5
votes
3answers
95 views

International Space Station

Recently, I have been going out to observe the ISS when it is within sight of my location. I have noticed that the ISS, based on the time that I have to observe the space station during any given ...
3
votes
2answers
414 views

Can things move faster than light inside the event horizon of a black hole?

Black Holes are regions of space where things get weird [Citation Needed]. Past the event horizon of a black hole, any moving particle instantaneously experiences a gravitational acceleration towards ...
6
votes
2answers
58 views

Is the Astronomy community still concerned about the lumpyness of matter distribution in the universe?

A decade or so ago, when I was still a science undergrad, one of the open questions in astrophysics was to explain the uneven distribution of galaxies in the observable universe. That is, why did the ...

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