Questions regarding the action or process of observing a single object carefully to glean information.

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conditions of the early universe and inflation [duplicate]

According to our current understandings (The Inflation Theory) when the universe initially expanded it pushed space and time outward from a point. So if anything was present in the space at that ...
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How to calculate the LST of an astronomical object at a given height above the horizon [in degrees]?

My situation: I want to observe M52 at RA = 23h24m48s, DEC = +61deg35arcmin36arcsec from, let's say, Calar Alto at 37.23deg N and 2.546deg W. How can I calculate the Local Sidereal Time (LST) at ...
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1answer
240 views

What uncertainty does an error bar signify in astronomy?

When an astronomer talks about her/his topic and shows an X/Y-plot with error bars. What should one assume that those error bars represent? 1 standard deviation? Or 2? Or some specific significance ...
3
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1answer
57 views

How big will Apophis appear?

How big will Apophis appear in the sky at its closest point of approach in 2029? Will it compare to the moon? How long will it linger as it passes?
3
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1answer
106 views

Pinhole projector for the Transit of Mercury

Very quick and simple one today. What would be the best/optimal pinhole size for a pinhole projector to observe the transit of Mercury on May 9th? I want to get the optimum between resolution and ...
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1answer
102 views

Why would astronomers want to eclipse the Sun?

I've heard that some astronomers are building an artifical solar-eclipse ship, that should help us to dim the diffraction of the Sun. Why don't we just wait till night? What is the function of the ...
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2answers
127 views

How can apparent magnitude be negative?

What is the reason for that scale? Is it because otherwise defining an maximum would be too hard(?). Why do objects that are (apparently) brighter get assigned a smaller number (and down to negative)? ...
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2answers
108 views

Calculate time when star is above altitude 30°

To find the best observation time for an object, I'd like to calculate the time when it is 30° or more above the horizon. Local Sideral Time would be sufficient. To include that in my program, I need ...
2
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1answer
65 views

Given a collection of pixels, how to deduce the flux from them?

I've obtained the coordinates of brightest pixels from different images (.fits files) using Python. I want to get the flux of each pixel. How do I go about finding out the flux?
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1answer
120 views

Does CIBER Experiment from Caltech suggest that there can be lots of stars which are not in any galaxy?

My question is about the implications of the observations recently made by the Cosmic Infrared Background Experiment, or CIBER, from Caltech. I've read at Caltech web site: "The total light ...
5
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2answers
115 views

Are there any galaxies which fell out of sight horizon due to cosmic expansion?

If farthest galaxies run away from us with acceleration making them exceed speed of light, we should expect them to disappear from sky among time with increasing quantity. Did we observe this? Can we ...
4
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1answer
47 views

How Soon Could a Waxing Crescent Moon Be Seen?

Question: Apart from a Solar Eclipse, How much time is needed until a Waxing Crescent Moon be seen following a New Moon? Would the time of year be significant? The Vernal Equinox + 1 Month. ...
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1answer
38 views

Parabolic or hyperbolic trajectories

According to Newton's laws, the trajectories for the two-body problem are conics: either ellipses, or parabolas or hyperbolas. Of course periodic motions require Ellipses and in the Solar system these ...
4
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2answers
183 views

What are some night sky objects I could see with my Celestron UpClose 20x50 Porro Binocular?

I bought this binocular because I've read countless times that one should start with a pair of binoculars before diving into telescopes. I've seen details of the moon and I can notice Venus round ...
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1answer
26 views

Moon SHAPE calculator

I have seen a lot of information about moon phase calculation, but need an accurate moon shape calculator/algorithm given the observer's position and time. This implies that the illuminated portion ...
0
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2answers
97 views

Color of planets

I am developing an astronomy software and need to know the color of each planet in the Solar System, when observed with the naked eye. I cannot find that information after googling for a while. Is ...
7
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1answer
45 views

What is the schedule for science runs of aLIGO (and VIRGO)?

Advanced LIGO seems to operate only intermittently. Is there a schedule for at what times it will be able to register new gravity waves? Even if no formal schedule is available, what main factors ...
2
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1answer
66 views

Could science be lost if a phenomena is observed before predicted? [closed]

An observation could validate the predictions made by a previous theory. If something unpredicted is observed, then a new theory which is compatible with the observation should make predictions which ...
5
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2answers
146 views

Why when we look through a telescope in space, do the billions of stars not block our view from seeing further?

I know that we are able to "see back into time" by looking very far away through telescopes such as the Hubble telescope, but my question is, wouldn't you run into at least a couple of stars that were ...
4
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1answer
97 views

Have we seen a black hole?

Have we actually seen a black hole out there? By "seen" I mean "recorded a em-spectrum image of gravitational lensing caused by object believed to be black hole".
4
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1answer
43 views

Calculating longitude from star culmination

Here is the problem: I need to calculate longitude of observing place. And I know time (in UTC+1) of star culmination (Sirius) and star altitude. I also know RA (right ascension) and Dec (declination) ...
4
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1answer
122 views

Could Venus or Mercury have a moon that we haven't detected?

Let's consider Mars' two moons for a moment. They're small, not even spherical, and most likely are captured asteroids. They weren't discovered until the late 1800's. Telescopes are much more powerful ...
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5answers
5k views

Why hasn't the “9th Planet” been detected already?

In the comments to this question, there was considerable doubt placed as to the subject of if the so called "9th planet" really exists. That wasn't really the intent of the previous question, so I ask ...
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1answer
454 views

Why does the moon sometimes appear giant and a orange red color near the horizon?

I've read various ideas about why the moon looks larger on the horizon. The most reasonable one in my opinion is that it is due to how our brain calculates (perceives) distance, with objects high ...
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2answers
312 views

Can I look at the sky and find the day of the week?

Suppose I wake up from a coma on a desert island in the 19th century (i.e. we already use the Gregorian calendar but have no satellites yet). I have a clear view of the sky and a couple of days to ...
6
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1answer
51 views

When do Mercury/Venus reach greatest elevation at sunset/twilight for a given location?

On what day does Mercury reach its greatest elevation (in degrees from the horizon) at sunset a given location? The obvious answer is the day of Mercury's greatest elongation from the Sun, but, ...
5
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1answer
120 views

What good evidence exists for the 9th planet as spoken of by Caltech?

I'm sure Caltech has answered this in some way, but I think it's a good question have on this site. What good evidence exists for the 9th planet as spoken of by Caltech? As I see it, Caltech has ...
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3answers
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What wavelength to best detect the “9th planet”?

We know that the reflected sunlight will make detecting the 9th planet very difficult in the visible light. Is there another band that will be more likely to detect it? What is the surface temperature ...
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2answers
410 views

How long should it take for us to observationally determine if Caltech's Planet Nine is really there?

Caltech just released a report that says there is possibly a large (10 earth mass) planet in a remote orbit (10 - 20 thousand year) that explains a lot of observations of Kuiper Belt objects. How long ...
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0answers
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Is atmospheric turbulence irrelevant for ExoPlanetary transits and radial velocity measurments?

Atmospheric turbulence is known to scatter photons in a quasi-random way along their path throughout the atmosphere, resulting in lower imaging resolution than would have been anticipated by ...
5
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3answers
269 views

Should this photo of the sun's surface actually be white?

If I'm told correctly (eg. What Color is the Sun?) that the sun is actually white, should the photo on that page actually be white too? Is it just doctored to meet peoples expectations?: Likewise ...
2
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2answers
124 views

Why isn't everything yellow(ish)?

I understand that - although appearing yellow - the sun is white. And that this is because the other light colours are scattered by the atmosphere. For example: Google image search for "The Sun from ...
12
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1answer
231 views

Have we ever observed a body, such as a large asteroid, “hitting” the Sun?

Some other SE questions about launching ICBM's into the sun got me wondering whether we have ever observed an object on a path that intersected with the Sun? How close did it get?
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2answers
53 views

How often and over what period is Earth’s rotation averaged to compute UT1?

I understand that UT1 (and for that matter UT0, UT2, etc.) are based on averages of actual earth rotation, and serve as a form of mean solar time. However it’s not clear to me when these averages are ...
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3answers
324 views

How Would a Neutron Star Actually Appear?

Having seen many pictures produced by artists of neutron stars and planets that orbit some of them, I was wondering how a pulsar would appear to a human being, in visible light (assuming the intense ...
4
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1answer
94 views

Why would the Earth's solar analemma would be still a figue eight even if Earth's orbit was circular?

The Earth's solar analemma is a diagram showing the deviation of the Sun from its mean motion in the sky, as viewed from a fixed location on the Earth. ... For [a planet] with a circular orbit but ...
4
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1answer
46 views

What is an “arc” spectrum ?

I sometimes hear about astronomers using an arc spectrum to calibrate observations. For example a "He-Ar arc spectrum". What is an "arc" in this context? I assume it's nothing got to do with angles ...
3
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1answer
29 views

Standard conditions for a heliacal rising

I imagine there are several possible conditions for determining the time of a helical rising of a star, the elevation of the star at sunrise, the latitude of the observer, and the azimuth of the star. ...
4
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1answer
38 views

Why do spectroscopic binaries have approximate circular orbits?

So for an assignment I have to answer the question what I can conclude concerning the shape of the orbit, knowing that it is both an eclipsing and spectroscopic binary. Now, I think the answer I ...
2
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1answer
90 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 ...
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2answers
132 views

Stellarium 0.10.4: planet orbits change over time?

If I draw the orbit of Mars in stellarium 0.10.4 for 23 Sep 2015, it passes south of Chi Leonis: If I advance the date to 17 Oct 2015, however, the orbit of Mars correctly goes right through Chi ...
2
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0answers
85 views

What would this moving point of light be?

Tonight (10:00 PM EST Middlesex County, Mass.) when looking at the mostly clear sky I observed what I at first believed was a meteor. This point of light was moving east to northeast and that would be ...
3
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1answer
45 views

Planet-timer “device” from 1970s or 1980s possibly by Edmund Scientific

Many years ago (early 80s or late 70s), I bought a cardboard "device" which I think was called "Planet Timer" and I think was sold by Edmund Scientific. Does anyone have any information on this ...
6
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1answer
105 views

What is in the brightest area of the night sky?

When I look up in the night sky, I assume the brightest area, commonly known as "The Milky Way", is the Galactic Center of our home galaxy. But then I stumbled upon this illustration, which seems ...
39
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4answers
5k views

How does the Earth move in the sky as seen from the Moon?

I just want to be sure I am visualizing this correctly, because it seems odd. The Moon is tidally locked to the Earth but there are wobbles to its motion due to libration. So from a point on the ...
3
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1answer
73 views

Do neutrinos have as much information as photons do?

If neutrino detectors keep improving so that a fair number of neutrinos can be observed, would they be as informative for astronomy as photons are? They are of course a very valuable complement to ...
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2answers
565 views

why does venus flick?

I was watching Venus with the naked eye yesterday at about 7 pm and I noticed that it was flickering, almost like a star. I have always learned that planets don't flicker to the naked eye, only stars ...
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1answer
156 views

Calculate Dec and RA of a star from Euler angles and GPS data

I have 9DOF sensor (accelerometer, gyroscope, and magnetometer) that gives orientation via Euler angles (yaw, pitch, roll). Along with GPS data (latitude, longitude, elevation, time) this is passed to ...
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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 ...
4
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1answer
89 views

What's the distribution curve for meteor sightings?

I know that meteor showers have a "peak" observation time. What does the distribution in time look like? Is one side of the peak steeper/shallower or longer/shorter than the other side, and if so, ...