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Yes, the shape of the constellation does and will change over time. All the stars have their own peculiar velocities and have some random motion which over time will ruin all the constellations. However, Even though the stars are moving at rapid speeds, to us, in our sky, due to their enormous distance from us, they appear to move extremely slowly and the ...
37
Constellations are human constructs to make sense of the night sky. When you are trying to find your way around, it helps to "chunk" stars into patterns and assign those groupings names. When I want to point out a particular object in the sky (say Polaris, the North Star), I start by pointing out a familiar constellation (say Ursa Major, the Big Dipper). ...
34
As mentioned, these are the Pleiades, and the belt of Orion. These are visible in the South at this time of year. The Big and Little Dippers are in the North, so turn around. The best way to find them is a map:
I've marked the approximate edge of your photo, with Orion, the V of the Hyades and the small cluster called the Pleiades. The big dipper is much ...
23
The stars are so immensely far away that to the human eye there would be no noticeable difference. The nearest stars are moving roughly 1.5 arcsecond wrt. the background when viewed from Earth's position with half a year's interval (i.e. half a revolution around the Sun). Mars' orbit is only 50% larger, but the human eye cannot resolve better than roughly ...
22
If you set the date to 2018-04-06, Stellarium shows the Moon and planets in positions matching the example image.
Any good planetarium software should produce a similar result.
Most likely the vendor cut and pasted two screenshots (note the seam) for April 2018, overlaid "January 1973," and hoped customers would not check.
Perhaps you could ask them to send ...
20
It is true that, for an observer standing on Earth, the daytime sky blocks out our ability to see the stars (with the exception that stars are visible during a total eclipse).
It is possible to get pretty close. In a different post, it was asked if the the center of the galaxy is only visible for 1/2 of the days of the year. That post is here: Is it true ...
20
Here's an animation I found that gives you an idea of the movements and timescales involved:
It depicts the estimated movement of the Orion Constellation from 3 million years in the past to 3 million years in the future.
18
What you describe is a technique called averted vision and takes advantage of the arrangement of cones and rods, two types of light sensitive elements within the eye:
The retina contains two types of photoreceptors, rods and cones. The
rods are more numerous, some 120 million, and are more sensitive than
the cones. However, they are not sensitive to ...
18
The terms refer to the viewing angle, i.e. from which direction do we observe a (disk) galaxy. If we happen to be located roughly in its plane of rotation, we see it from the "edge", whereas if we are more or less above or below its plane, we see its "face".
To make a more quantitative statement, the orientation is described by the inclination angle $i$, ...
16
No, it does not. The constellations are fixed (on time scales long enough for humans to consider as fixed, at least) patterns of stars which exist on the celestial sphere. This celestial sphere is a coordinate system which has the Earth at its center. From the Earth's perspective, the sun rises and sets at the same rate as the constellations, but as the ...
16
I just want to add pictures to augment pela's answer.
Just google "edge on galaxy" and "face on galaxy" to find results like these, it is entirely about the viewing angle.
Example of a face on galaxy (Messier 74)
Example of an edge on galaxy (NGC 891)
15
If it was rather small, I suppose you were looking at the Pleiades, which is an open star cluster (not a constellation).
Take a look at this web application: https://stellarium-web.org/
You can set a time and location and find constellations and other objects really easily.
15
Yes, those are the Pleiades. The form corresponds exactly to the photo below:
(source: Star-Gazing - the disk below the Pleiades is Venus, this is a photo from April)
As @theWrongAlice says, they're not a constellation, but they are part of Taurus (the Bull).
13
If the stars are all similar distance from us, like the Pleiades, then yes, you could find a place from where the stars would appear in a similar pattern and brightness, but the pattern would be a mirror image.
You can't do it when the stars are significantly different distances because they wouldn't look the same. Most constellations are a range of ...
13
The group of stars circled at the top of the photo is a star cluster named Pleiades. The Pleiades are in the constellation of Taurus.
The group of stars circled at the bottom of the photo is part of the constellation of Orion. The three vertical stars on the left side of the circle are the belt stars of Orion. His upper body is to the upper left, and one leg ...
13
You can see the constellation Orion on this photo:
(Screenshot from Stellarium)
Aligning the original photo with this screenshot, I found the highlighted stars to be the following:
11
You possibly are confused by these two entries in Wikipedia (click on the quotations to go to the original distinct entries:
Canis Minor contains only two stars brighter than the fourth magnitude, Procyon (Alpha Canis Minoris), with a magnitude of 0.34, and Gomeisa (Beta Canis Minoris), with a magnitude of 2.9.
and
This is the list of [56] notable stars ...
11
The short answer is there are no galaxies in or around Orion that are visible to the naked eye.
The International Astronomical Union (IAU) has some simplified star charts for each constellation. The charts show galaxies the brightest galaxies that are visible in amateur telescopes as red ovals. The chart for Orion and the surrounding constellations show no ...
10
Constellations and asterisms are generally not proximate in space, but rather happen to be nearby only when viewed from Earth. From Wikipedia's article on asterisms:
Like constellations, asterisms are in most cases composed of stars which, while they are visible in the same general direction, are not physically related, often being at significantly ...
10
The device that you saw is called a nocturnal. It calculates the local time based on the month of the year and the position of Polaris and one or more other stars.
Since stars change position throughout the night, they can be used to determine time; but the positions of stars change throughout the year, so the input of the month of the year is needed. ...
9
The constellation in the lower right is Orion, characterized by its famous "belt" of 3 stars. The two stars in the top center and top right belong to Taurus, the latter being Aldebaran. I am not sure about the stars to the left, it seems like it's part of Gemini.
8
Nope, that constellation is Perseus.
8
These are the Latin word endings.
Latin nouns change their endings according to how the word is being used. English doesn't have this grammar. But note how the word "I" changes to "my". In Latin you would call "my" the genitive form of "I" The good people at https://latin.stackexchange.com/ can give more explanation.
For example, "Leo" is a third ...
8
Quoting from wikipedia:
Canis Minor was one of the original 48 constellations formulated by Ptolemy in his second-century Almagest, in which it was defined as a specific pattern (asterism) of stars; Ptolemy identified only two stars and hence no depiction was possible. The Ancient Greeks called the constellation προκυων/Procyon, "coming before the dog", ...
8
The constellations are artifacts of visual pattern recognition, many dating back to antiquity.
As the stars are distributed unevenly, naturally some constellations are larger than others.
Ptolemy catalogued 48 of them around 150 CE.
The other 40 were added between 1596 and 1763, either to cover the far southern sky or to fill gaps between the older figures.
...
8
There are no naked eye galaxies in Orion. The brightest galaxies in Orion are NGC1924 (a magnitude 13 barred spiral, 130 million lightyear distant) and IC421 (a magnitude 14 spiral that hosted a supernova visible in 2013, 150 million ly distant)
In the neighbouring constellation of Eriandus is NGC1600 (a large elliptical galaxy with magnitude 12 with an ...
8
In such situations, I find Astrometry.net particularly helpful. Feeding it your image, I got this result:
Of course, the stars Pleione, Sterope, and Taygeta are enough to identify the Pleiades.
While in this case it's fairly easy to identify the Pleiades by inspection alone and verify this, for less recognisable cases Astrometry.net is a very handy tool. ...
7
Aabaakawad's answer highlights an important aspect of any constellation: They are defined by a surface area on the sky, behind which many, many stars hide. In order to answer just how many stars, you'll have to ask "above which brightness threshold?".
I think you should accept his answer, but I have two comments:
"…if one were to map every star visible to ...
7
To calculate that you will have to build a 3D model based upon the distance of each of their stars and then calculate the resulting 3D object's volume. I know this may not answer the question, but I give the way to answering it. It's not an easy job.
Making a quick guess based upon the distances of the stars of both constellations in my opinion I guess the ...
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