<p>The proper motion of most stars is extremely small, measured in milli-arcseconds per year, where an arcsecond is 1/3600 of a degree, and of course milli means a thousandth of that. One degree is 3,600 arcseconds, or 3,600,000 milli-arcseconds.</p>
<p>Except Barnard's Star.
<a href="https://www.kqed.org/quest/41313/do-constellations-change-over-time" rel="nofollow noreferrer">https://www.kqed.org/quest/41313/do-constellations-change-over-time</a></p>
<p>Ancient maps small insight.
<a href="https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/" rel="nofollow noreferrer">https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/</a></p>
<p>I think, the most work that have been done since ancient times, is matching names and different culture's maps under IAU.</p>

CC BY-SA 4.0
2021-08-12T14:53:21.833Z
I would not expect stars to *move* meaningfully, but it would seem plausible that there might be some stars which consistently appeared in star maps from 2,000 years ago but are no longer visible, or stars which are naked-eye visible today but for some reason never showed up in maps until fairly recently.  If either of those things happened, it would be apparent even stars' positions were only recorded +/- one degree.
supercat
CC BY-SA 4.0
2021-08-12T17:32:36.717Z
Barnard's Star is, of course, too faint to be seen with the naked eye and would not appear on any ancient star maps.  There are a few stars with high proper motion that are visible to the naked eye (Groombridge 1830, 61 Cygni, Epsilon Indi), but they're either quite faint or aren't often visible to the Northern-Hemisphere civilizations that would have been likely to make detailed star maps.
Michael Seifert
CC BY-SA 4.0
2021-08-12T20:34:01.480Z
@supercat: how would it be plausible that stars might appear or disappear like that?
TonyK
CC BY-SA 4.0
2021-08-12T20:57:20.623Z
@TonyK: Stars last a long time, but not forever, and stars which emit light can be formed from gas clouds that previously hadn't.  For any individual star, such events would be vanishingly rare on human time scales, but there are almost certainly stars whose light first reached Earth in the time since people first started charting the skies, and there have almost certainly been stars that lasted long enough for their light to have been observed, but died out long enough ago that light from them has stopped reaching Earth.
supercat
CC BY-SA 4.0
2021-08-12T21:46:01.400Z
@supercat Star formation is a process that takes hundreds of thousands or millions of years, so you won’t really have “stars whose light first reached Earth in the time since people first started charting the skies”.
Peter Erwin
CC BY-SA 4.0
2021-08-12T22:44:38.927Z
@PeterErwin: Some stars are estimated to produce visible light for 10 million years; others may do so for longer or shorter times.  If 5,000 stars are naked-eye visible, then watching them for 2,000 years would represent ten million star-years' worth of observation.  That would seem to fall within the range where a star might plausibly be seen to appear from nowhere or disappear into nothingness.
supercat
CC BY-SA 4.0
2021-08-12T23:00:14.827Z
@supercat, your logic is flawed. A star takes many thousands of years to reach its full brightness, and many thousands of years to fade away (unless it goes nova). So there won't be any stars that have changed noticeably in the last 2000 years, unless they exploded with a bang.
TonyK
CC BY-SA 4.0
2021-08-12T23:12:20.387Z
@TonyK: Fair point, though of course some stars do go supernova. Further, during the time a star is forming or fading out, the brightness would change by many orders of magnitude, so it would seem plausible that there might be stars which are easily naked-eye-visible today but weren't visible thousands of years ago, or that were naked eye visible back then but are today dimmer than other stars that weren't visible back then.  I think I overestimated the probability of such "changes", but if an ancient civilization's star map has a star that isn't easily visible today...
supercat
CC BY-SA 4.0
2021-08-12T23:13:05.667Z
...such a discrepancy would seem more meaningful than an apparent shift in relative position.
supercat
CC BY-SA 4.0
2021-08-13T09:40:46.333Z
@supercat Historical novae (classical novae and supernovae) have always been described as completely "new" stars (*nova* = "new" in Latin; "guest stars" in traditional Chinese astronomy), not as a previously known star that got brighter.
Peter Erwin
CC BY-SA 4.0
2021-08-13T18:49:56.750Z
@PeterErwin: Certainly there must have been numerous times throughout the ages when a star went from being previously-unnoticed to barely noticeable, and there would likely have been no way to distinguish at the time whether the star had previously not been there, had been present but dimmer, or had always been present at the same brightness but it had gone unnoticed until someone with particularly good eyes happened to notice it.  If a star which was first cataloged in 1600 were today brighter than many other stars that were cataloged centures before, however, ...
supercat
CC BY-SA 4.0
2021-08-13T18:50:25.973Z
...that might suggest that the brightness of the star had changed with time.
supercat
CC BY-SA 4.0
2021-08-13T20:41:25.120Z
@supercat Your hypothetical "barely noticeable" stars would almost certainly not be in a map or catalog from 2000 years ago (Ptolemy's catalog had only $\sim$ 1000 stars). In any case, this is getting very far afield from the OP.
Peter Erwin
CC BY-SA 4.0
2021-08-18T02:53:43.220Z
You say "Ancient maps small insight" but you don't explain what that insight is. Since your previous 2 paragraphs don't address the question, it's important that you [edit] your answer to add the necessary detail, for example a summary of what the linked website says (assuming it is actually relevant to the question about matching ancient star maps to contemporary ones to demonstrate a change in position). :-)
Chappo Hasn't Forgotten
CC BY-SA 4.0
2021-10-16T09:05:25.287Z
@supercat do not be discouraged by the naysayers. There are a few stars that brighten considerably or fade on timescales of years, decades or centuries. Betelgeuse might be an example. Mira variables certainly are (Mira changes from being invisible to magnitude ~2-3 on timescales of a year). The star P Cygni notably brightened to third magnitude about 400 years ago and then faded again. So which stars appear in catalogues at any particular time could be of of interest.
ProfRob
CC BY-SA 4.0
2021-08-11T15:36:41.627Z
2021-08-11T15:36:41.627Z
Lariliss
<blockquote>
<p>Are there any old/ancient star maps that we can compare to today’s and see drastic differences?</p>
</blockquote>
<p>Yes, we can! Well, depending on some definitions (e.g. “star”, “map”, “drastic”).</p>
<p>The universe is not static (see <a href="https://en.wikipedia.org/wiki/Big_Bang" rel="nofollow noreferrer">Big Bang</a>), everything is moving, space is expanding, stars are born, live, age, and die (see <a href="https://en.wikipedia.org/wiki/Stellar_evolution" rel="nofollow noreferrer">stellar evolution</a>). Thus, we do have changes. And we are able to observe them – observation led to the theories given above. “Observe” does not necessarily mean “see with the naked eyes”, though. (It can even mean “deduce from observing a large number of objects of the same type”.) The changes generally happen at an astronomical time scale, see <a href="https://astronomy.stackexchange.com/questions/45248/are-there-any-old-ancient-star-maps-that-we-can-compare-to-today-s-and-see-drast/45252#45252">the answer of Lariliss</a>. Therefore, generally the changes in one human lifetime or even several of those are too small to be seen (but see below). (If “map” means “astronomical catalogue”, position changes are seen therein.)</p>
<p>“old/ancient star maps”, as I understand it, are not about the position of stars in the universe! First, it is not about stars at all. “A star is an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity” (<a href="https://en.wikipedia.org/wiki/Star" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Star</a>). That is not what an ancient star map would record. That ancient star map would record visible (luminous/light reflecting/…) “dots” in the night sky. This excludes our Sun, although it is a star (by the recent definition), but includes for example <a href="https://en.wikipedia.org/wiki/Supernova" rel="nofollow noreferrer">supernovae</a> (former stars), <a href="https://en.wikipedia.org/wiki/Nova" rel="nofollow noreferrer">novae</a>, <a href="https://en.wikipedia.org/wiki/Comet" rel="nofollow noreferrer">comets</a>, <a href="https://en.wikipedia.org/wiki/Asteroid" rel="nofollow noreferrer">asteroids</a>, <a href="https://en.wikipedia.org/wiki/Nebula" rel="nofollow noreferrer">nebula</a>, other planets in our solar system, our Moon, to name a few. Changes in the observation of those objects can be seen in much shorter time spans. The (super-)novae are explicitly named such, i.e. <em>nova</em> meaning new (star, although it is not a new star but a bright dot in the night sky where before there was no dot visible). When “map” means “depiction of luminous dots in the night sky”, then there would be maps without the (super-)nova, and later maps with it, maps showing a comet and maps not showing it. The Moon changes from “new” (i.e. completely dark) to full to new in one <a href="https://en.wikipedia.org/wiki/Lunar_month" rel="nofollow noreferrer">lunar month</a>. The other planets circle the Sun not synchronized to the Earth circling the Sun, thus changing their position in the sky. Comets come and go, and some come again (see <a href="https://en.wikipedia.org/wiki/List_of_periodic_comets" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/List_of_periodic_comets</a>). Thus there are observable changes.</p>
<p>Another point is that the “old/ancient star maps” would not record the positions of those dots in the universe, but the observed, <em>apparent</em> positions on the sky. There are drastic changes of the apparent positions due to changes of the position of the observer. Movement of the observer does not mean traveling from north to south pole (which would also lead to quite different observations, see <a href="https://en.wikipedia.org/wiki/Northern_celestial_hemisphere" rel="nofollow noreferrer">Northern</a> and <a href="https://en.wikipedia.org/wiki/Southern_celestial_hemisphere" rel="nofollow noreferrer">Southern</a> celestial hemisphere) but sitting down at one point of the surface of the Earth and letting the Earth do all the motion. So, what does the Earth do to the unsuspecting observer of the sky? <a href="https://www.coursehero.com/study-guides/astronomy/the-sky-above/" rel="nofollow noreferrer">https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/</a> gives some good explanations (and figures!):</p>
<p>Earth rotates around its own axis. This leads to (apparent!) rise and down of Sun, Moon, “stars” (meaning dots in the night sky). “As Earth rotates about its axis, the sky appears to turn in the opposite direction around those celestial poles (Figure 3)” at <a href="https://www.coursehero.com/study-guides/astronomy/the-sky-above/" rel="nofollow noreferrer">https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/</a>. Photographs of the night sky at different times of one night show quite different positions of the “stars”.</p>
<p>Earth rotates around the Sun (OK, around the common centre of gravity of Sun and Earth, which lays in the Sun but not in the centre of the Sun, happy now?) in one <a href="https://en.wikipedia.org/wiki/Sidereal_year" rel="nofollow noreferrer">sidereal year</a>. When positioned at the Earth’ poles, that does not drastically change your direction of view. But when positioned at the equator, you would look in quite the opposite direction (very simple model, not drawn to scale):
<a href="https://i.sstatic.net/yR7CU.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/yR7CU.gif" alt="View from earth with 1/2 year difference: opposite directions" /></a></p>
<p>And in the opposite direction there are different “stars”, i.e. during the year the “stars” seem to move, see Figure 5: Constellations on the Ecliptic of <a href="https://www.coursehero.com/study-guides/astronomy/the-sky-above/" rel="nofollow noreferrer">https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/</a>. Photographs of the night sky at different times of the year show different stars. (Please do not stand at the poles just do disprove this, otherwise I will point out the <a href="https://en.wikipedia.org/wiki/Stellar_parallax" rel="nofollow noreferrer">parallax</a>.)</p>
<p>And this is not complicated enough: The rotational axis of the Earth, the <a href="https://en.wikipedia.org/wiki/Axial_tilt" rel="nofollow noreferrer">obliquity</a>, is tilted and even “oscillates between 22.1 and 24.5 degrees on a 41,000-year cycle“ (<a href="https://en.wikipedia.org/wiki/Axial_tilt" rel="nofollow noreferrer">ibid.</a>). Thus a change of the tilt moves the position of the horizon against the celestial sphere, and a star, which was just barely visible above the horizon might vanish below it over the years. I remember reading about a “star map” drawn on a wall of a historic building (age: around 1,500 years), where that happened, but I do not remember the source.</p>
<p>And this is not complicated enough: The axis shows <a href="https://en.wikipedia.org/wiki/Axial_precession" rel="nofollow noreferrer">Axial precession</a>: “In astronomy, axial precession is a gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis. In particular, it can refer to the gradual shift in the orientation of Earth's axis of rotation in a cycle of approximately 26,000 years.” This again leads to apparent movement of stars, see <a href="https://en.wikipedia.org/wiki/Axial_precession#History" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Axial_precession#History</a>, shift of the equinox and (!) shift of the zodiac:</p>
<blockquote>
<p>“There are two different zodiacs which divide the ecliptic into twelve
zodiac signs: the tropical zodiac with twelve sections, each with a
30° arc on the ecliptic, which is astronomically oriented to the
equinoxes and solstices, and the sidereal zodiac, which is oriented to
the - differently sized - constellations in the area of the ecliptic.
When the astrological system was developed in Hellenistic Alexandria,
probably from the 3rd century BC onwards, the tropical and sidereal
zodiacs still largely coincided, because the stars were equated as
indicators of the seasons. Compared to that time, however, the two
zodiacs today are about 30° out of phase with each other. So if, for
example, the Sun is currently in the zodiac sign of Capricorn at the
beginning of January, it is spatially in the constellation of
Sagittarius. The reason for this is that the Earth's axis, which is
decisive for the seasons, lurches - similar to a spinning top, but
very slowly, namely one round in about 25,800 years; this process is
known as precession. From the Earth's point of view, the point of
Aries moves backwards through the constellations of different sizes at
a speed of 1° in about 72 years.” (translated from <a href="https://de.wikipedia.org/wiki/Tierkreiszeichen#Tropischer_und_siderischer_Tierkreis" rel="nofollow noreferrer">https://de.wikipedia.org/wiki/Tierkreiszeichen#Tropischer_und_siderischer_Tierkreis</a>).</p>
</blockquote>
<p>“the Sun is currently in the zodiac sign of Capricorn at the beginning of January, it is spatially in the constellation of Sagittarius” – that is a drastic, observable difference, isn’t it? 30° is quite big. And “one round in about 25,800 years” is no problem: “A 32,500 year old carved ivory Mammoth tusk could contain the oldest known star chart (resembling the constellation Orion). It has also been suggested that drawing on the wall of the Lascaux caves in France dating from 33,000 to 10,000 years ago could be a graphical representation of the Pleiades, the Summer Triangle, and the Northern Crown.” (<a href="https://en.wikipedia.org/wiki/History_of_astronomy#Early_history" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/History_of_astronomy#Early_history</a>)</p>
<p>More “is” than “could” was in the 2nd millennium BC: “The oldest accurately dated star chart appeared in ancient Egyptian astronomy in 1534 BC. The earliest known star catalogues were compiled by the ancient Babylonian astronomers of Mesopotamia in the late 2nd millennium BC, during the Kassite Period (ca. 1531–1155 BC).” (<a href="https://en.wikipedia.org/wiki/Star_chart" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Star_chart</a>) 3,500 years before present allow for some (apparent) movement: 3,500 years/72 years is nearly 50°! Nevertheless it could be argued, that the constellations did not (apparently) move (in space), but are at the same place but at another time in the year, i.e. moved in time instead of space. Fun fact: The stars (this time talking about the luminous spheroids of plasma) are not even at the positions, where we see their light today – they were at those positions when they emitted the light, which reaches us today, and then moved away. For stars visible with the naked eye, farthest away is V762 Cassiopeiae in 16,308 light-years according to <a href="https://cosmoknowledge.com/farthest-star-you-can-see-with-the-unaided-eye/" rel="nofollow noreferrer">https://cosmoknowledge.com/farthest-star-you-can-see-with-the-unaided-eye/</a>.</p>
<p>At <a href="https://en.wikipedia.org/wiki/Archaeoastronomy#Recreating_the_ancient_sky" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Archaeoastronomy#Recreating_the_ancient_sky</a> we read:</p>
<blockquote>
<p>“Not only does the Earth rotate, it wobbles. The Earth's axis takes
around 25,800 years to complete one full wobble. The effect to the
archaeoastronomer is that stars did not rise over the horizon in the
past in the same places as they do today. Nor did the stars rotate
around Polaris as they do now. In the case of the Egyptian pyramids,
it has been shown they were aligned towards Thuban, a faint star in
the constellation of Draco. The effect can be substantial over
relatively short lengths of time, historically speaking. For instance
a person born on 25 December in Roman times would have been born with
the Sun in the constellation Capricorn. In the modern period a person
born on the same date would have the Sun in Sagittarius due to the
precession of the equinoxes.”</p>
</blockquote>
<p>The alignment at Thuban instead of Polaris is not a map, but the pyramids are quite big, thus I think it counts.</p>
<p>And this is not complicated enough: There is also <a href="https://en.wikipedia.org/wiki/Apsidal_precession" rel="nofollow noreferrer">Apsidal precession</a>, <a href="https://en.wikipedia.org/wiki/Stellar_parallax" rel="nofollow noreferrer">Stellar parallax</a>, the <a href="https://en.wikipedia.org/wiki/Sun#Motion_and_location" rel="nofollow noreferrer">Sun rotates around the centre of our galaxy</a>, and our galaxy, the <a href="https://en.wikipedia.org/wiki/Milky_Way" rel="nofollow noreferrer">Milky Way</a>, moves in our <a href="https://en.wikipedia.org/wiki/Local_Group" rel="nofollow noreferrer">Local Group</a>, which also moves. There is also the apparent movement of the position of stars, which for real is the deflection of light by a mass, which the light passes (see e.g. <a href="https://en.wikipedia.org/wiki/Eddington_experiment#Theory" rel="nofollow noreferrer">Eddington experiment</a> and <a href="https://en.wikipedia.org/wiki/Gravitational_lens" rel="nofollow noreferrer">Gravitational lens</a>).</p>
<p>We have (apparent) change of position of stars (et al.), ancient viewed positions are shown to be different from recent ones. The question in the text below the title of OP’s question is somewhat different, Peter Erwin and Lariliss already answered that and Jacopo Tissino added the &gt;&gt;&quot;map&quot; (a statue, really) representing the stars as seen in, roughly, 125BCE&lt;&lt;. A paper (or papyrus or drawing in a tomb) remains to be found.</p>

CC BY-SA 4.0
2021-10-15T18:02:15.380Z
2022-07-07T08:00:37.413Z
2022-07-07T08:00:37.413Z
Stephen
<p>In practice, you're probably not going to get anything useful from ancient star <em>maps</em>, for several reasons:</p>
<ol>
<li>Very few of them actually survive from more than a few hundred years ago.</li>
<li>Maps (and visual diagrams in general) are hard to accurately reproduce if you don't having printing, so a diagram from a document originally produced, say, 2000 years ago may be rather distorted if the oldest copy you have was made only 1000 years ago, and was itself most likely a copy of a copy of a copy...</li>
<li>Even a genuine 2000-year-old map probably wouldn't have the accuracy for you to tell whether an apparent shift in the relative positions of stars was due to actual proper motion or just due to sloppiness in making the original map.</li>
</ol>
<p>What you <em>can</em> potentially use are ancient <em>catalogs</em> with numerical coordinates of stars. This is what Edmund Halley did in the early 1700s, when he compared modern measurements of the positions of stars against their coordinates from the catalogs of Hipparchus, Timocharus, and Ptolemy, and argued that Sirius, Aldebaran, and Arcturus were all shifted by various offsets (15 to 31 arc minutes) compared to their positions 1800 years ago or so. (He also pointed out that in Tycho Brahe's catalog, finished in 1598, Sirius was about 2 arc minutes north of where it was now, indicating the stellar motion had been continuous.) See <a href="http://articles.adsabs.harvard.edu/pdf/1942ASPL....4..103A" rel="noreferrer">Aitken 1942</a> for a reproduction of Halley's 1718 publication.</p>
<p>The cumulative proper motions of Sirius, Arcturus, and Aldebaran over the last 2000 years amount to something like half to a full diameter of the moon, so if you <em>had</em> an accurate map from 2000 years ago, you could probably notice the difference (though it would be relatively subtle). But, again, I don't think such a map exists.</p>

CC BY-SA 4.0
2021-08-11T20:23:51.950Z
And of course, Hipparchus had access to data spanning several centuries (probably from [Babylonian sources](https://en.wikipedia.org/wiki/Hipparchus#Babylonian_sources)), which enabled him to discover the precession of the equinoxes.
PM 2Ring
CC BY-SA 4.0
2021-08-14T15:30:21.093Z
We actually have a "map" (a statue, really) representing the stars as seen in, roughly, 125BCE: it is the Farnese Atlas, it is based on Hipparchus' catalogue, and a study by Schaefer (https://journals.sagepub.com/doi/10.1177/002182860503600202) used the stars' positions in the atlas as a reference to give a date to which they refer.
Jacopo Tissino
CC BY-SA 4.0
2021-08-11T16:32:58.107Z
2021-08-11T18:13:38.197Z
2021-08-11T18:13:38.197Z
Peter Erwin
<p>Stars move through the sky very slowly, which is not noticeable in a human lifespan. I’m aware of proper motion of Barnard's Star and things of the sort but I’d like to obtain a noticeable record of changes from 1000s of years ago.</p>
<p>There are old star maps I’ve seen online but it is hard to even understand what’s going on. Are there any sources that can explain it simply to me or even show side by side example of old/ancient and new/modern?</p>

CC BY-SA 4.0
2021-08-11T14:07:31.203Z
Hi! If you can supply some links to sites that you've found that were hard to understand, that would be very helpful.
Daddy Kropotkin
CC BY-SA 4.0
2021-08-11T20:25:58.503Z
The Babylonians collected over 7 centuries of data in their [astronomical diaries](https://www.livius.org/articles/concept/astronomical-diaries/).
PM 2Ring
CC BY-SA 4.0
2021-08-12T14:24:35.407Z
Look up Anthony Avenis books for more on ancient astronomy. I really like his writings. He was on StarTalk , too. www.anthonyfaveni.com
Raphael
CC BY-SA 4.0
2021-10-17T16:03:53.103Z
Your question is excellent. You asked if we "can see" those two words are the definition of observe. You also used the term "drastic changes" this would mean noticeable also part of your question. "Noticable" is a comparative word meaning you want evidence that is large enough to prove a point as opposed to changes which are so small as to exceed the accuracy of the measuring device or process. It's like buying a digital weight scale whose minimum unit is 1 gram but you are looking for hundredths of a gram differences. That process produces no evidence let alone proof.
Stephen's answer to your
Robert1954
<history><star-maps><apparent-motion>
Are there any old/ancient star maps that we can compare to today’s and see drastic differences?
Beans
# Are there any old/ancient star maps that we can compare to today’s and see drastic differences?

(Asked by: username_0 on 2021-08-11)

Stars move through the sky very slowly, which is not noticeable in a human lifespan. I’m aware of proper motion of Barnard's Star and things of the sort but I’d like to obtain a noticeable record of changes from 1000s of years ago.

There are old star maps I’ve seen online but it is hard to even understand what’s going on. Are there any sources that can explain it simply to me or even show side by side example of old/ancient and new/modern?

**Tags:** history, star-maps, apparent-motion

> **Comments:**
> **username_1**: Hi! If you can supply some links to sites that you've found that were hard to understand, that would be very helpful.  
> **username_2**: The Babylonians collected over 7 centuries of data in their [astronomical diaries](https://www.livius.org/articles/concept/astronomical-diaries/).  
> **username_3**: Look up Anthony Avenis books for more on ancient astronomy. I really like his writings. He was on StarTalk , too. www.anthonyfaveni.com  
> **username_4**: Your question is excellent. You asked if we "can see" those two words are the definition of observe. You also used the term "drastic changes" this would mean noticeable also part of your question. "Noticable" is a comparative word meaning you want evidence that is large enough to prove a point as opposed to changes which are so small as to exceed the accuracy of the measuring device or process. It's like buying a digital weight scale whose minimum unit is 1 gram but you are looking for hundredths of a gram differences. That process produces no evidence let alone proof. username_12's answer to your  

---

## 3 answers

### Answer by username_9 on 2021-08-11. Score: 43 | Accepted answer

In practice, you're probably not going to get anything useful from ancient star *maps*, for several reasons:

1. Very few of them actually survive from more than a few hundred years ago.
2. Maps (and visual diagrams in general) are hard to accurately reproduce if you don't having printing, so a diagram from a document originally produced, say, 2000 years ago may be rather distorted if the oldest copy you have was made only 1000 years ago, and was itself most likely a copy of a copy of a copy...
3. Even a genuine 2000-year-old map probably wouldn't have the accuracy for you to tell whether an apparent shift in the relative positions of stars was due to actual proper motion or just due to sloppiness in making the original map.

What you *can* potentially use are ancient *catalogs* with numerical coordinates of stars. This is what Edmund Halley did in the early 1700s, when he compared modern measurements of the positions of stars against their coordinates from the catalogs of Hipparchus, Timocharus, and Ptolemy, and argued that Sirius, Aldebaran, and Arcturus were all shifted by various offsets (15 to 31 arc minutes) compared to their positions 1800 years ago or so. (He also pointed out that in Tycho Brahe's catalog, finished in 1598, Sirius was about 2 arc minutes north of where it was now, indicating the stellar motion had been continuous.) See [Aitken 1942](http://articles.adsabs.harvard.edu/pdf/1942ASPL....4..103A) for a reproduction of Halley's 1718 publication.

The cumulative proper motions of Sirius, Arcturus, and Aldebaran over the last 2000 years amount to something like half to a full diameter of the moon, so if you *had* an accurate map from 2000 years ago, you could probably notice the difference (though it would be relatively subtle). But, again, I don't think such a map exists.

> **Comments:**
> **username_2**: And of course, Hipparchus had access to data spanning several centuries (probably from [Babylonian sources](https://en.wikipedia.org/wiki/Hipparchus#Babylonian_sources)), which enabled him to discover the precession of the equinoxes.  
> **username_13**: We actually have a "map" (a statue, really) representing the stars as seen in, roughly, 125BCE: it is the Farnese Atlas, it is based on Hipparchus' catalogue, and a study by Schaefer (https://journals.sagepub.com/doi/10.1177/002182860503600202) used the stars' positions in the atlas as a reference to give a date to which they refer.  

---

### Answer by username_5 on 2021-08-11. Score: 3

The proper motion of most stars is extremely small, measured in milli-arcseconds per year, where an arcsecond is 1/3600 of a degree, and of course milli means a thousandth of that. One degree is 3,600 arcseconds, or 3,600,000 milli-arcseconds.

Except Barnard's Star.
<https://www.kqed.org/quest/41313/do-constellations-change-over-time>

Ancient maps small insight.
<https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/>

I think, the most work that have been done since ancient times, is matching names and different culture's maps under IAU.

> **Comments:**
> **username_6**: I would not expect stars to *move* meaningfully, but it would seem plausible that there might be some stars which consistently appeared in star maps from 2,000 years ago but are no longer visible, or stars which are naked-eye visible today but for some reason never showed up in maps until fairly recently.  If either of those things happened, it would be apparent even stars' positions were only recorded +/- one degree.  
> **username_7**: Barnard's Star is, of course, too faint to be seen with the naked eye and would not appear on any ancient star maps.  There are a few stars with high proper motion that are visible to the naked eye (Groombridge 1830, 61 Cygni, Epsilon Indi), but they're either quite faint or aren't often visible to the Northern-Hemisphere civilizations that would have been likely to make detailed star maps.  
> **username_8**: @username_6: how would it be plausible that stars might appear or disappear like that?  
> **username_6**: @username_8: Stars last a long time, but not forever, and stars which emit light can be formed from gas clouds that previously hadn't.  For any individual star, such events would be vanishingly rare on human time scales, but there are almost certainly stars whose light first reached Earth in the time since people first started charting the skies, and there have almost certainly been stars that lasted long enough for their light to have been observed, but died out long enough ago that light from them has stopped reaching Earth.  
> **username_9**: @username_6 Star formation is a process that takes hundreds of thousands or millions of years, so you won’t really have “stars whose light first reached Earth in the time since people first started charting the skies”.  
> **username_6**: @username_9: Some stars are estimated to produce visible light for 10 million years; others may do so for longer or shorter times.  If 5,000 stars are naked-eye visible, then watching them for 2,000 years would represent ten million star-years' worth of observation.  That would seem to fall within the range where a star might plausibly be seen to appear from nowhere or disappear into nothingness.  
> **username_8**: @username_6, your logic is flawed. A star takes many thousands of years to reach its full brightness, and many thousands of years to fade away (unless it goes nova). So there won't be any stars that have changed noticeably in the last 2000 years, unless they exploded with a bang.  
> **username_6**: @username_8: Fair point, though of course some stars do go supernova. Further, during the time a star is forming or fading out, the brightness would change by many orders of magnitude, so it would seem plausible that there might be stars which are easily naked-eye-visible today but weren't visible thousands of years ago, or that were naked eye visible back then but are today dimmer than other stars that weren't visible back then.  I think I overestimated the probability of such "changes", but if an ancient civilization's star map has a star that isn't easily visible today...  
> **username_6**: ...such a discrepancy would seem more meaningful than an apparent shift in relative position.  
> **username_9**: @username_6 Historical novae (classical novae and supernovae) have always been described as completely "new" stars (*nova* = "new" in Latin; "guest stars" in traditional Chinese astronomy), not as a previously known star that got brighter.  
> **username_6**: @username_9: Certainly there must have been numerous times throughout the ages when a star went from being previously-unnoticed to barely noticeable, and there would likely have been no way to distinguish at the time whether the star had previously not been there, had been present but dimmer, or had always been present at the same brightness but it had gone unnoticed until someone with particularly good eyes happened to notice it.  If a star which was first cataloged in 1600 were today brighter than many other stars that were cataloged centures before, however, ...  
> **username_6**: ...that might suggest that the brightness of the star had changed with time.  
> **username_9**: @username_6 Your hypothetical "barely noticeable" stars would almost certainly not be in a map or catalog from 2000 years ago (Ptolemy's catalog had only $\sim$ 1000 stars). In any case, this is getting very far afield from the OP.  
> **username_10**: You say "Ancient maps small insight" but you don't explain what that insight is. Since your previous 2 paragraphs don't address the question, it's important that you [edit] your answer to add the necessary detail, for example a summary of what the linked website says (assuming it is actually relevant to the question about matching ancient star maps to contemporary ones to demonstrate a change in position). :-)  
> **username_11**: @username_6 do not be discouraged by the naysayers. There are a few stars that brighten considerably or fade on timescales of years, decades or centuries. Betelgeuse might be an example. Mira variables certainly are (Mira changes from being invisible to magnitude ~2-3 on timescales of a year). The star P Cygni notably brightened to third magnitude about 400 years ago and then faded again. So which stars appear in catalogues at any particular time could be of of interest.  

---

### Answer by username_12 on 2021-10-15. Score: 1

> Are there any old/ancient star maps that we can compare to today’s and see drastic differences?

Yes, we can! Well, depending on some definitions (e.g. “star”, “map”, “drastic”).

The universe is not static (see [Big Bang](https://en.wikipedia.org/wiki/Big_Bang)), everything is moving, space is expanding, stars are born, live, age, and die (see [stellar evolution](https://en.wikipedia.org/wiki/Stellar_evolution)). Thus, we do have changes. And we are able to observe them – observation led to the theories given above. “Observe” does not necessarily mean “see with the naked eyes”, though. (It can even mean “deduce from observing a large number of objects of the same type”.) The changes generally happen at an astronomical time scale, see [the answer of username_5](https://astronomy.stackexchange.com/questions/45248/are-there-any-old-ancient-star-maps-that-we-can-compare-to-today-s-and-see-drast/45252#45252). Therefore, generally the changes in one human lifetime or even several of those are too small to be seen (but see below). (If “map” means “astronomical catalogue”, position changes are seen therein.)

“old/ancient star maps”, as I understand it, are not about the position of stars in the universe! First, it is not about stars at all. “A star is an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity” (<https://en.wikipedia.org/wiki/Star>). That is not what an ancient star map would record. That ancient star map would record visible (luminous/light reflecting/…) “dots” in the night sky. This excludes our Sun, although it is a star (by the recent definition), but includes for example [supernovae](https://en.wikipedia.org/wiki/Supernova) (former stars), [novae](https://en.wikipedia.org/wiki/Nova), [comets](https://en.wikipedia.org/wiki/Comet), [asteroids](https://en.wikipedia.org/wiki/Asteroid), [nebula](https://en.wikipedia.org/wiki/Nebula), other planets in our solar system, our Moon, to name a few. Changes in the observation of those objects can be seen in much shorter time spans. The (super-)novae are explicitly named such, i.e. *nova* meaning new (star, although it is not a new star but a bright dot in the night sky where before there was no dot visible). When “map” means “depiction of luminous dots in the night sky”, then there would be maps without the (super-)nova, and later maps with it, maps showing a comet and maps not showing it. The Moon changes from “new” (i.e. completely dark) to full to new in one [lunar month](https://en.wikipedia.org/wiki/Lunar_month). The other planets circle the Sun not synchronized to the Earth circling the Sun, thus changing their position in the sky. Comets come and go, and some come again (see <https://en.wikipedia.org/wiki/List_of_periodic_comets>). Thus there are observable changes.

Another point is that the “old/ancient star maps” would not record the positions of those dots in the universe, but the observed, *apparent* positions on the sky. There are drastic changes of the apparent positions due to changes of the position of the observer. Movement of the observer does not mean traveling from north to south pole (which would also lead to quite different observations, see [Northern](https://en.wikipedia.org/wiki/Northern_celestial_hemisphere) and [Southern](https://en.wikipedia.org/wiki/Southern_celestial_hemisphere) celestial hemisphere) but sitting down at one point of the surface of the Earth and letting the Earth do all the motion. So, what does the Earth do to the unsuspecting observer of the sky? [https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/](https://www.coursehero.com/study-guides/astronomy/the-sky-above/) gives some good explanations (and figures!):

Earth rotates around its own axis. This leads to (apparent!) rise and down of Sun, Moon, “stars” (meaning dots in the night sky). “As Earth rotates about its axis, the sky appears to turn in the opposite direction around those celestial poles (Figure 3)” at [https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/](https://www.coursehero.com/study-guides/astronomy/the-sky-above/). Photographs of the night sky at different times of one night show quite different positions of the “stars”.

Earth rotates around the Sun (OK, around the common centre of gravity of Sun and Earth, which lays in the Sun but not in the centre of the Sun, happy now?) in one [sidereal year](https://en.wikipedia.org/wiki/Sidereal_year). When positioned at the Earth’ poles, that does not drastically change your direction of view. But when positioned at the equator, you would look in quite the opposite direction (very simple model, not drawn to scale):
[![View from earth with 1/2 year difference: opposite directions](https://i.sstatic.net/yR7CU.gif)](https://i.sstatic.net/yR7CU.gif)

And in the opposite direction there are different “stars”, i.e. during the year the “stars” seem to move, see Figure 5: Constellations on the Ecliptic of [https://courses.lumenlearning.com/astronomy/chapter/the-sky-above/](https://www.coursehero.com/study-guides/astronomy/the-sky-above/). Photographs of the night sky at different times of the year show different stars. (Please do not stand at the poles just do disprove this, otherwise I will point out the [parallax](https://en.wikipedia.org/wiki/Stellar_parallax).)

And this is not complicated enough: The rotational axis of the Earth, the [obliquity](https://en.wikipedia.org/wiki/Axial_tilt), is tilted and even “oscillates between 22.1 and 24.5 degrees on a 41,000-year cycle“ ([ibid.](https://en.wikipedia.org/wiki/Axial_tilt)). Thus a change of the tilt moves the position of the horizon against the celestial sphere, and a star, which was just barely visible above the horizon might vanish below it over the years. I remember reading about a “star map” drawn on a wall of a historic building (age: around 1,500 years), where that happened, but I do not remember the source.

And this is not complicated enough: The axis shows [Axial precession](https://en.wikipedia.org/wiki/Axial_precession): “In astronomy, axial precession is a gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis. In particular, it can refer to the gradual shift in the orientation of Earth's axis of rotation in a cycle of approximately 26,000 years.” This again leads to apparent movement of stars, see <https://en.wikipedia.org/wiki/Axial_precession#History>, shift of the equinox and (!) shift of the zodiac:

> “There are two different zodiacs which divide the ecliptic into twelve
> zodiac signs: the tropical zodiac with twelve sections, each with a
> 30° arc on the ecliptic, which is astronomically oriented to the
> equinoxes and solstices, and the sidereal zodiac, which is oriented to
> the - differently sized - constellations in the area of the ecliptic.
> When the astrological system was developed in Hellenistic Alexandria,
> probably from the 3rd century BC onwards, the tropical and sidereal
> zodiacs still largely coincided, because the stars were equated as
> indicators of the seasons. Compared to that time, however, the two
> zodiacs today are about 30° out of phase with each other. So if, for
> example, the Sun is currently in the zodiac sign of Capricorn at the
> beginning of January, it is spatially in the constellation of
> Sagittarius. The reason for this is that the Earth's axis, which is
> decisive for the seasons, lurches - similar to a spinning top, but
> very slowly, namely one round in about 25,800 years; this process is
> known as precession. From the Earth's point of view, the point of
> Aries moves backwards through the constellations of different sizes at
> a speed of 1° in about 72 years.” (translated from <https://de.wikipedia.org/wiki/Tierkreiszeichen#Tropischer_und_siderischer_Tierkreis>).

“the Sun is currently in the zodiac sign of Capricorn at the beginning of January, it is spatially in the constellation of Sagittarius” – that is a drastic, observable difference, isn’t it? 30° is quite big. And “one round in about 25,800 years” is no problem: “A 32,500 year old carved ivory Mammoth tusk could contain the oldest known star chart (resembling the constellation Orion). It has also been suggested that drawing on the wall of the Lascaux caves in France dating from 33,000 to 10,000 years ago could be a graphical representation of the Pleiades, the Summer Triangle, and the Northern Crown.” (<https://en.wikipedia.org/wiki/History_of_astronomy#Early_history>)

More “is” than “could” was in the 2nd millennium BC: “The oldest accurately dated star chart appeared in ancient Egyptian astronomy in 1534 BC. The earliest known star catalogues were compiled by the ancient Babylonian astronomers of Mesopotamia in the late 2nd millennium BC, during the Kassite Period (ca. 1531–1155 BC).” (<https://en.wikipedia.org/wiki/Star_chart>) 3,500 years before present allow for some (apparent) movement: 3,500 years/72 years is nearly 50°! Nevertheless it could be argued, that the constellations did not (apparently) move (in space), but are at the same place but at another time in the year, i.e. moved in time instead of space. Fun fact: The stars (this time talking about the luminous spheroids of plasma) are not even at the positions, where we see their light today – they were at those positions when they emitted the light, which reaches us today, and then moved away. For stars visible with the naked eye, farthest away is V762 Cassiopeiae in 16,308 light-years according to <https://cosmoknowledge.com/farthest-star-you-can-see-with-the-unaided-eye/>.

At <https://en.wikipedia.org/wiki/Archaeoastronomy#Recreating_the_ancient_sky> we read:

> “Not only does the Earth rotate, it wobbles. The Earth's axis takes
> around 25,800 years to complete one full wobble. The effect to the
> archaeoastronomer is that stars did not rise over the horizon in the
> past in the same places as they do today. Nor did the stars rotate
> around Polaris as they do now. In the case of the Egyptian pyramids,
> it has been shown they were aligned towards Thuban, a faint star in
> the constellation of Draco. The effect can be substantial over
> relatively short lengths of time, historically speaking. For instance
> a person born on 25 December in Roman times would have been born with
> the Sun in the constellation Capricorn. In the modern period a person
> born on the same date would have the Sun in Sagittarius due to the
> precession of the equinoxes.”

The alignment at Thuban instead of Polaris is not a map, but the pyramids are quite big, thus I think it counts.

And this is not complicated enough: There is also [Apsidal precession](https://en.wikipedia.org/wiki/Apsidal_precession), [Stellar parallax](https://en.wikipedia.org/wiki/Stellar_parallax), the [Sun rotates around the centre of our galaxy](https://en.wikipedia.org/wiki/Sun#Motion_and_location), and our galaxy, the [Milky Way](https://en.wikipedia.org/wiki/Milky_Way), moves in our [Local Group](https://en.wikipedia.org/wiki/Local_Group), which also moves. There is also the apparent movement of the position of stars, which for real is the deflection of light by a mass, which the light passes (see e.g. [Eddington experiment](https://en.wikipedia.org/wiki/Eddington_experiment#Theory) and [Gravitational lens](https://en.wikipedia.org/wiki/Gravitational_lens)).

We have (apparent) change of position of stars (et al.), ancient viewed positions are shown to be different from recent ones. The question in the text below the title of OP’s question is somewhat different, username_9 username_9 and username_5 already answered that and username_13 added the >>"map" (a statue, really) representing the stars as seen in, roughly, 125BCE<<. A paper (or papyrus or drawing in a tomb) remains to be found.


---

