The science dealing with objects and phenomena located beyond Earth. In particular, this applies to observations and data. At its core, astronomy is the physically informed cataloging and classifying of the contents of the universe in order to better understand what is out there.

learn more… | top users | synonyms

5
votes
5answers
58 views

Which current big Earth-based telescopes are equipped with adaptive optics?

I know only that the VLT is equipped with adaptive optics (AO) to bypass atmospheric distortion. Is it the only one, or have other telescopes been build with AO in the optical and infrared spectrum?
6
votes
4answers
66 views

Does the current light pollution set a fundamental limit for the range of Earth-based telescopes?

As far as I know, all deep-sky pictures are captured with the Hubble Space Telescope. If there would be no atmospheric distortion, could we make deeper pictures in the optical spectrum with ...
4
votes
4answers
461 views

Can the Hubble telescope bring any star into focus?

Lets say I am talking about a view like this supernova - 13 billions light year away. In short can Hubble bring any star into focus in the entire universe? And if so, to what definition? I also ...
4
votes
2answers
237 views

Is the Milky Way significantly easier to see by astronauts?

On Earth the Milky Way appears very ghostly when looked at with the naked eye, somewhat easier to see when NOT looking directly at it. Is it substantially easier to see by astronauts in space or is ...
10
votes
1answer
2k views

How dense are nebulae?

How functionaly dense are nebulae? Are they so sparse they are only visible from an interstellar or intergalactic perspective or would you be unable to see your hand in one? Do they vary widely in ...
10
votes
3answers
259 views

Why did the ancients fail to discover that the Earth orbits the Sun?

The ancients observed that the Sun and the 'fixed' stars rotated about the Earth. They were also aware that the Earth was spherical. They performed many astronomical measurements on the planets - ...
6
votes
3answers
1k views

Solar system, visible stars and deep sky objects

Since I've seen that galaxies are often called "deep sky objects", as opposed to individual stars, does this mean that all visible stars in the night sky actually only belong to The Milky Way Galaxy? ...
3
votes
8answers
2k views

Seeking Recommendation for Celestron Firstscope Eyepiece Upgrade

I have a Celestron Firstscope telescope and like it overall for my location and the amount of observing I do. I am disappointed in my view of the planets with the scope. What would be a good eye piece ...
10
votes
5answers
836 views

How is it possible for astronomers to see something 13B light years away?

In a NPR News story from a few years back: "A gamma-ray burst from about 13 billion light years away has become the most distant object in the known universe." I'm a layman when it comes ...
7
votes
4answers
367 views

Applying the Maxwell–Boltzmann statistics to astrophysical objects

Quoting Wikipedia: In statistical mechanics, Maxwell–Boltzmann statistics describes the statistical distribution of material particles over various energy states in thermal equilibrium, when the ...
18
votes
5answers
220 views

Given a photo of the Moon, taken from Earth, is it possible to calculate the position of the photographer's site?

Given a photo of the Moon, taken from Earth, is it possible to calculate the position (Earth longitude and latitude) of the photographer's site? I am thinking about photos taken with a normal camera ...
9
votes
2answers
742 views

How can a Population III star be so massive?

How can a Population III star have a mass of several hundred solar masses? Normally the limit is about 100 solar masses.
5
votes
5answers
2k views

Curiosity Rover (MSL): specification / dimensions

I have been looking all over and I can't find a detailed specification about the Curiosity Rover. The length is about 10 feet but it would be cool to find out the dimensions of the wheels, clearance ...
3
votes
1answer
137 views

Is the orbit of earth around the sun chaotic?

The orbit of the earth seems to be very predictable. But as it is a many-body problem having sun, earth, moon, jupiter and so on, is it really that stable or will it start making strange movements ...
2
votes
1answer
194 views

What examples are there of fuzzy concepts in astronomy?

What examples are there of fuzzy concepts in astronomy? In particular, how fuzzy are the boundaries between different types of stars? As an example of a fuzzy concept I'm thinking of the planet/brown ...
4
votes
3answers
422 views

What are the easiest ways to get data out of a FITS file without a library?

There are FITS libraries for most programming languages (see this list), but FITS is a simple enough format that it should be pretty easy to extract data without the need for such libraries or ...
5
votes
2answers
131 views

Advice sought on choosing a camera for a Meade LX10

I have a Meade LX10 and have never done any astrophotography (except with some computerised SBIG ST9s on my university's LX200s). I would like to get started at home, but could do with some advice on ...
7
votes
2answers
637 views

Finding Directions using moon

Is it possible to find directions just by looking at moon(not full bright)? I was curious to use the clue that if moon is half lit then the direction in which it is lit will it be east?
6
votes
1answer
27 views

Lack of exoplanet missions in the decadal survey

In recent exoplanet meeting "The Next 40 Years of Exoplanets", there was much discussion of the inablity of the community to agree on whether to support coronagraph missions or interferometer ...
0
votes
2answers
135 views

Space Interferometry Mission (SIM) cancellation [closed]

NASA's SIM mission was recently cancelled despite \$600 million being spent already over the last ten years. Has this \$600m been completely wasted or has any new technology been developed that could ...
0
votes
2answers
63 views

Study of exoplanets reaching saturation point [closed]

In recent exoplanet meeting The Next 40 Years of Exoplanets, it was mentioned a few times that the field/topic is becoming saturated. In what ways is it becoming saturated, and can you see the effect ...
12
votes
2answers
26 views

Why are binary objects so critical to astronomy?

There are a lot of astronomical objects out there to study but binary objects seem to get more attention. Why is this? What makes binary objects (stars, Kuiper Belt Objects, black holes, galaxies, ...
3
votes
3answers
100 views

What was the apparent magnitude of the June 15th 2011 lunar eclipse?

My plan was to observe and estimate the apparent magnitude of the Moon during totality of the June 2011 lunar eclipse, but the clouds rolled in at the exact moment, so I couldn't make any useful ...
8
votes
2answers
307 views

Silicon-based life [closed]

My question may not be suitable here, because it's more of astrobiology. Life as we know it is carbon based. Is life based on silicon possible? What would the conditions for habitability for ...
7
votes
1answer
168 views

Could two colliding comets near Earth cause devastation?

Let's say two comets crashed into each other. If it was 0.1 AU away from the Earth, would the collision cause mass destruction here, or not affect us at all?
8
votes
3answers
2k views

What would happen if the polar ice caps of Mars melted?

My dad told me that Mars' polar ice caps are made of H2O and CO2. If they melt, would it add an atmosphere to Mars and allow life?
17
votes
5answers
318 views

Why don't we have a better telescope than the Hubble Space Telescope?

The Hubble Space Telescope (HST) was launched in 1990, more than 20 years ago, but I know that it was supposed to be launched in 1986, 24 years ago. Since it only took 66 years from the fist plane to ...
14
votes
2answers
680 views

What if our Sun were located in the middle of a globular cluster?

Say you took our current solar system and relocated it deep in the heart of a globular cluster such as Omega Centauri. What would the night sky look like? Would the starshine of nearby stars be enough ...
11
votes
1answer
61 views

Why did the june 2011 lunar eclipse last so long?

It was kind of hard to miss the lunar eclipse this week, although I didn't see it in person (Sod's law means that on every relatively major astronomical event clouds cover where I am). From what I ...
26
votes
4answers
5k views

Why is a new moon not the same as a solar eclipse?

Forgive the elementary nature of this question: Because a new moon occurs when the moon is positioned between the earth and sun, doesn't this also mean that somewhere on the Earth, a solar eclipse ...
8
votes
3answers
368 views

Significance of letters in Hertzsprung-Russell (H-R) diagram

The Hertzsprung-Russell diagram that categorizes star types uses the letter codes O, B, A, F, G, K, and M to indicate a star's temperature/color. Hottest (blue) is O and coolest (red) is M. What do ...
7
votes
3answers
58 views

Is a rogue 'exoplanet' classed as a exoplanet?

Given that the term planet strictly (according to the IAU) refers to a body around the sun, rogue planets can't be called that, so I assume they must be called rogue exoplanets? But do they even ...
8
votes
1answer
297 views

Could the earth have another moon?

First, to clarify: I'm not asking if perhaps there's a moon that we haven't found yet. The question is, theoretically, would the earth be able to have another stable moon in addition to the current ...
7
votes
2answers
45 views

Where to find Lunar Eclipse data

I am wondering whether there's a good resource to find data about upcoming Lunar Eclipses. For example, showing the percentage of the eclipse over time. Such as: 17:23 GMT - 0%, 17:40 GMT - 10%, etc. ...
4
votes
6answers
159 views

What possible science could we do during the 2012 Venus transit? [closed]

I had previously asked about how useful everyday solar physics data is to other astronomers ... But about a year from now, we will have another Venus transit, where Venus will pass between the sun and ...
16
votes
2answers
237 views

Recommend good book(s) about the “scientific method” as it relates to astronomy/astrophysics?

I am interested in astronomy/astrophysics, but I am not science major (I am a computer science graduate). Facts and results of the field are presented to the public without showing how these ...
18
votes
2answers
391 views

How would the night sky appear at the edge of the galaxy?

In Isaac Asimov's Foundation Series, there is a planet named Terminus which is believed to be the planet farthest from the galactic center. There are almost no visible stars in its sky, only the ...
17
votes
4answers
1k views

Does the Moon's core still contain significant heat?

On earth, using earth-sheltering techniques can significantly reduce the temperature fluctuations on a structure. Would the same statement be true as well on the Moon? Does the Moon's core still ...
15
votes
5answers
2k views

What do the colors in false color images represent?

Every kid who first looks into a telescope is shocked to see that everything's black and white. The pretty colors, like those in this picture of the Sleeping Beauty Galaxy (M64), are missing: The ...
9
votes
2answers
2k views

Cameras in Voyager probes

I've always wondered about the cameras in the space probes, especially in the Voyagers. 1) What kind of cameras do they have? Digital? (What kind of sensor and megapixel count?) Analog? (Do they ...
2
votes
2answers
228 views

Why can't you see meteors, but you can see comets from the moon?

Why can't you see meteors from the moon and why can you see comets?
10
votes
1answer
197 views

How many earth-sized planets have been discovered outside the solar system?

How many earth-sized planets have been discovered outside our solar system? Is there a combined registry of them anywhere? Where might I look for more information?
4
votes
3answers
162 views

Shapes of galaxies

I've heard most of galaxies are spiral or ellipsoid shaped. Is it true? If true, then why they form in such shapes? How did arms of the spiral galaxies form?
13
votes
4answers
6k views

How do astronomers measure the distance to a star or other celestial object?

How do scientists measure the distance between objects in space? For example, Alpha Centauri is 4.3 light years away.
13
votes
3answers
185 views

How are newly discovered objects (stars, planets, galaxies…) named?

When a new astronomical object (star, planet, galaxy, comet, etc.) is discovered, what is the official procedure to name it? Who decides about the name of it? Can they be changed in time? Extra ...
12
votes
2answers
114 views

What is the most distant object from the Earth that a spacecraft has visited to date?

What is the most distant object from the earth that a spacecraft visited has visited so far? What was the mission and when did it happen?
11
votes
3answers
2k views

Calculations of apparent magnitude

I was attempting to do some calculations of apparent magnitude to help solidify my understanding of the topic, but have been running into some confusion. According to Wikipedia, the apparent ...
7
votes
2answers
72 views

What latitude is needed before you can reliably see Omega Centauri?

What latitude is needed before you can reliably see the globular cluster Omega Centauri, say it reaches 20 degrees above the horizon? What about if you are up on a hill looking down, what's the ...
6
votes
3answers
477 views

Binary stars' apparent magnitude

If you plot the apparent magnitude of a binary system (so you are unable to see 2 distinct stars) against time, it gives a repeating 'M' effect. (from http://accessscience.com/) Assuming one star ...
7
votes
2answers
1k views

What does the sky look like to human eyes from orbit?

There are numerous pictures, obviously, of the blackness of space from the shuttle, the space station, and even the moon. But they all suffer from being from the perspective of a camera, which is not ...