0
votes
0answers
3 views

damage from an Asteroid

If an Asteroid, the size of the one that killed off the dinosaurs , passed by very close to the Earth but still remained outside of Earth's atmosphere, would it cause any damage ?
1
vote
2answers
40 views

How did water get on Earth

I recently read that water more then likely got here by comets (carrying water) hitting the Earth. However it also it says the impact of a comet hitting the Earth is much greater then an atomic bomb. ...
1
vote
1answer
35 views

Why did Earth need material from comets to assemble the raw materials for life?

It's often speculated that matter from comets played a crucial role in the development of life on Earth. For example, Maps of Time says, Many of the ingredients of the early atmosphere (including ...
17
votes
4answers
3k views

Can our Sun become a black hole

Does every star become a black hole? Is there any probability that our sun can become a black hole? If yes then is it on its way to become a black hole? what is the current state of sun as per the ...
0
votes
0answers
8 views

How can you determine the initial volume of a planet's atmosphere?

Since the surface pressure of a planet is determined by the mass of the column of gasses above it one would surmise that to determine the pressure you must know the volume and mass of the atmosphere. ...
1
vote
2answers
47 views

Find constellation over Earth coordinates on a specific date-time

I would like some help in finding the exact constellations, or some sort of visualization of the stars over an specific location an time. The idea is to find out the closest star or group of stars on ...
1
vote
2answers
41 views

What is the direction of the movement of the solar system in relation to the galaxy's plane

I got from this answer that the axis of the solar system is tilted of about 63 degrees in relation to that of our galaxy, so I can assume that we move through space (at least locally) roughly in a ...
1
vote
3answers
64 views

Do we still use the term “astronomical unit” nowadays?

An astronomical unit is defined as the measurement of distance between Earth and our Sun, my question is since distances between celestial objects beyond our solar system are vast and unimaginable ...
0
votes
2answers
101 views

Naming of the planets of the solar system

Planets of the solar system have been named with Roman mythology gods names. I have a few questions on my mind concerning that subject for a while: Who decided to name them like this? When did the ...
-2
votes
0answers
27 views

The More I Measure, The Faster I Travel [on hold]

Basically, the theme is "The More I Measure The Faster I Travel" As part of an antithesis, I am trying to destroy this statement. Can anyone help?
0
votes
0answers
9 views

Is there a threshold on distance/size for a tidal locking?

I know that some systems tend to tidal locking (such as earth-moon), which occurs basically because the difference in the gravitational pull on one side is significantly different from the pull on the ...
1
vote
2answers
54 views

Enhanced Star-Gazing with Special Glasses

I watched a video yesterday on how telescopes not only magnify images but also increase the amount of light entering into your eye, allowing you to see things not normally visible with naked eye. ...
1
vote
0answers
5 views

Can an asteroid have a molten core? [migrated]

Most natural satellites in our solar systems is expected to contain a fission furnace at it's core, some of these moons do have a striking resemblance to an asteroid. I'm wondering if we could ...
6
votes
3answers
165 views

Aren't there more naked-eye-visible stars in the Milky Way plane?

Most stars which are visible to the naked eye are within 1,000 light years. The Sun is inside the Orion arm which has a diameter of about 3,500 light years. Thus, all stars (with very few exceptions) ...
1
vote
1answer
65 views

What are the azimuths of the planets' orbits?

I am creating a virtual solar system model and I want it to be as realistic as possible (e.g. orbits are ellipses, not circles, and orbits are oriented correctly, not all coplanar). In order for me ...
3
votes
1answer
105 views

Given a date obtain latitude and longitude where is the sun zenith

Searching is easy to find terminator line (frontier between day and night) or the position of the sun in the sky given a position on the earth and a time; but I can't find how to obtain where is the ...
5
votes
1answer
35 views

How does radio bandwidth restrict the choice and use of science payload on interplanetary probes?

I asked a question here about returning to Earth a physical memory capsule along with soil samples, as a complement to radio operations as today. This might return a much larger amount of data ...
3
votes
1answer
38 views

average number of exoplanets in a system

I was just wondering what the normal amount of planets is in a star system, because in my mind 8 planets seems like a relatively large amount. so are we above average? can we even see all the ...
1
vote
1answer
62 views

Gravitational pull needed to keep a gas in atmosphere

How can you determine the gravitational force needed to keep a particular gas in the atmosphere of a planet (for example, carbon dioxide (CO2))? I came across the following formula ...
-1
votes
0answers
22 views

Best compact telescope for rugged use [on hold]

Is there a general variety of telescopes that are compact and rugged enough to be taken on outdoor outings, such as backpacking with exposure to cold, rain, and potential impacts?
1
vote
2answers
63 views

How much of the Milky Way is visible to the naked eye from earth?

When we see the Milky Way on a dark night are we seeing the bulk of the galaxy, or just our local arm? How much of the milky way is visible to the naked eye on a dark night?
1
vote
1answer
43 views

PowerSeeker 114Q

I just purchased a powerseeker 114q by Celestron. This is my very first telescope. I believe I assembled it correctly however I can't see anything out of it. Well I can see a small corner of an image. ...
-1
votes
0answers
12 views

How to evaluate limiting magnitude of a telescope

Given that the limiting magnitude of a 5cm telescope is 10, what is the limiting magnitude of a 2.5m telescope? I assume that the limiting magnitude for this problem is a function of light gathering ...
19
votes
3answers
4k views

Why there is no smoke around the Sun?

Where there is fire, there is always smoke. So why there isn't any smoke near the Sun?
0
votes
0answers
15 views

Dynamic Method-Please explain

I have, for years, been an Astronomy and physics nerd. For the first while, I was a total astronomy nerd. Then I slowly transitioned into physics and have been, for less than a year, a physics nerd. ...
1
vote
0answers
21 views

Is there a simple, analytical formula for the lunar phase brightness curve?

Brightness of the lunar disk varies as a function of phase angle. This phenomenon is very well established, as is the increase in brightness at low phase angles. Is there a simple analytical formula ...
2
votes
1answer
580 views

Is there any planet/star bigger than VY Canis Majoris?

Compared to VY Canis Majoris, our Sun is more like a speck of space dust. Is there any planet or star which is known to us that is bigger than the VY Canis Majoris?
1
vote
1answer
51 views

What is the typical resolving power of the largest optical telescopes?

I'd like to estimate the typical resolving power of the largest optical telescopes. I've calculated the theoretical resolving power of the VLA for 21 cm light, $$R=\frac{\lambda}{B}=\frac{2.1 \times ...
-2
votes
1answer
21 views

A good book about the moon

Sorry if this isn't the best place to ask this but it's all I could think of. Could someone recommend a good informative book about the moon? I'm looking for one as a gift for a friend and possible ...
0
votes
2answers
209 views

When we see the Sun, do we actually see its past?

The Sun's rays hit our eyes around 8 minutes after they are emitted from the Sun. Does this mean that the Sun that we see is always the Sun as it was some 8 minutes before? I strongly think this must ...
3
votes
1answer
63 views

Is stacking welder's glasses a safe way to watch at the eclipse?

You can find in many place on the Internet that welder's glass #14 is good for looking at an eclipse. Tomorrow (March, 20th 2015 at 10:45 CET) there's a solar eclipse and yesterday I could only find ...
2
votes
2answers
91 views

What is the Northernmost Latitude of Saturn?

My wife and I were watching a TV show last night, which takes place in Salem, Massachusetts circa 1693. One character went to a particular place in the woods at a particular time to be exactly under ...
0
votes
0answers
15 views

SN1604, Former and Current Name of the Constellation Serphens

Kepler wrote 'De Stella nova in pede Serpentarii' describing the supernova of 1604, now known as SN1604. My understanding is that the constellations used by Kepler and the constellations used today ...
0
votes
0answers
10 views

How to convert horizontal coordinates using NOVAS?

I'm using NOVAS 3.1. I know that I can convert equatorial coordinates to horizontal coordinates using the equ2hor function. Is it possible to make NOVAS do the ...
0
votes
0answers
77 views

BIG Problem with the Planet definition

Ok, so Pluto is only ~1/13 the mass of the objects in "its orbit". This orbital region extends from 40 AU to 70 AU (semi major axes)- Now, just a minute. 30 AU is all the mass we are considering. Now, ...
1
vote
1answer
32 views

What were the challenges for the ancients to observe the orbit of the Moon (instead of Mars)?

Astrophysics can be said to have been founded by Johannes Kepler around the year 1600. He based his break-through science on data of the position of Mars in the sky and disproved the ancient ideas ...
1
vote
0answers
36 views

Were the Voyager Golden Records tested for being decoded?

I was wondering if the microgroove golden records they put on the Voyager spacecraft, along with instruction on how to decode it, were first put to the test with the subjects most likely to decode ...
3
votes
1answer
74 views

Sky view from Stellarium software vs. Sky view with naked eye

I'm slowly starting to interest in astronomy. Currently I'm enjoying in stargazing but unfortunately place where I live is very light polluted. I'm planing my vacation in a couple of months and one ...
1
vote
1answer
68 views

Is there a general term for epicycles, deferents, and eccentrics in Ptolemaic astronomy?

According to Ptolemy's (c. 150 CE) account of the motions of planets, planets moved in circular paths ("epicycles") around center points that in turn moved around the center of the earth along a path ...
0
votes
0answers
41 views

Lack of planets in the Oort Cloud

With the current news about the possibility of a planet in the Oort cloud, I was thinking, why is the matter in the Oort cloud distributed so? It makes sence that inside the planet region there is not ...
0
votes
0answers
13 views

Gravitational waves detector arm length and GW wavelength

What is the relation between the arm length of gravitational wave detectors and the wavelength of target gravitational waves? For example, LIGO detector has 4 km arms and detects waves with 10^2-10^4 ...
2
votes
1answer
26 views

.2015: When last did both New/Full moon in a fort-night cause an Eclipse?

Going through http://earthsky.org/…/dates-of-next-lunar-and-solar-eclipses I made the (what was for me - momentous) discovery that March 20, 2015 - New moon - is a Solar Eclipse, and that the ...
1
vote
1answer
29 views

Why solar eclipse paths are symmetrical?

Reading upon the eclipse of March 20, 2015, I stumbled upon this page: http://www.timeanddate.com/eclipse/list-solar.html. What caught my eye is that for each year there are two eclipses whose paths ...
2
votes
0answers
54 views

Total solar eclipse, supermoon, and spring equinox all happening at the same time: anything special about this?

Today (March 20, 2015) is seeing a rare combination of the spring equinox, a total solar eclipse, and a supermoon. I am wondering if there is anything special astronomically about all three of these ...
2
votes
1answer
46 views

How rare are earth-like solar eclipses?

Solar eclipses on the earth are so spectacular because the moon has roughly the same size as the sun when viewed from the earth's surface. This is an incredible coincidence, and my guess is that it is ...
1
vote
0answers
27 views

Mars night sky - stars visible

How would the night sky look like from Mars surface. Would there be more stars visible or less (compared to Earth) Would they appear brighter/dimmer/same.
1
vote
2answers
55 views

What is a possible software for simulating binary star systems?

I would like to define both initial velocities and masses of components so that orbits may be either elliptical of hyperbolic. Is there any software to make such simulation? Unfortunately, Binary ...
1
vote
1answer
62 views

Method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle?

What is the method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? (Not from occlusion but actually visible on its own.) Further, ...
1
vote
1answer
41 views

What kind of telescope do I need to see most of the Jupiter's moons?

I have a simple Newtonian reflector telescope. Using it, I am able to see the Galilean moons of Jupiter. However, Jupiter has much more moons than that (Wikipedia says 67 have been discovered this ...
0
votes
0answers
14 views

How to learn data analysis for radio telescope?

I have done some research about Radio Astronomy to build a radio telescope with a number of arrays. I have read one of the prerequisites of working with radio telescope is a good knowledge about ...

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