Flat Earth debunks - Stars

{{pseudoastronomy}}
{{ArticleSeries|Flat Earth|the Flat Earth}}
Flat-Earthers have made several incorrect observations to claim the Earth is flat. This article refutes claims made by flat-Earthers about the stars.

=="But star trail photography proves that the Earth doesn't move!"==
[[File:Roller coaster.jpg|thumb|right|'''Flerfcoaster''': Flat-earthers like Eric Dubay [https://youtu.be/gz8d7SQwJho?feature=shared&t=279 claim] the star trails would be a mess if photographed from what they'd describe as a solar system roller coaster. In reality, a star trail photo is taken over 24 hour time period during which the Sun and Earth move an amount that causes negligible parallax. Dubay's video exaggerates this by running at roughly 15,000,000x speed, and even the illustration he shared (above) show this if one just counts some pixels. Earth's own rotation that causes the most noticeable effect, is either part of the star trail photo, or it's negated by the camera's equatorial mount.]]

[[File:All In A Spin Star trail.jpg|thumb|Star trail photography done in Chile, where stars revolve clockwise. A phenomenon that can't be explained on a flat Earth.]]
Although the theory isn't necessarily [[geocentrist]] (as one can technically still adopt a [[heliocentric]] [[worldview]] while holding to a belief in a flat Earth), flat-earthers almost always fall into that camp.

One particular claim is that long-duration star trail photographs do not show any movement of the stars other than that caused by the [[Earth's rotation]], the flat-earther's reasoning being that, if the Earth is moving so fast around the [[Sun]], the stars should appear smudged. This claim is symptomatic of all flat-earthers' false assumptions about the distance between us and celestial objects, or their inability or lack of willingness to perform basic [[math]]. This is most likely because {{wpl|Spherical trigonometry}} and astro-trigonometry are exact sciences, which ''only work'' in a spherical environment.<ref>P.E. Robinson (23 March 2003). "[https://www.youtube.com/watch?v=XUQAIldqPww Introductory Astronomy: Parallax, the Parsec, and Distances]". ''[[YouTube]]''.</ref> 

For example, let's consider a star trail photograph of the nearest star is taken for 12 hours on a 10,000-pixel-wide camera. The Earth would travel about 1,287,000 km during that time. The nearest naked-eye visible star is Alpha Centauri, which is 4.34 light-years (41 trillion kilometers) away. The star would appear to move 0.018 pixels.<ref group=note>Round earthers are just trying to pull the wool over the eyes of thinking people with math!</ref>

The stars in flat Earth model run into all sorts of problems:

* '''Only a subset of stars is visible, anywhere''': There are 2 points to capture star trails and see a star that appears to not move in the sky. These are the famous Polaris in the north and Sigma Octantis in the south. All the stars in the sky rotate around these 2 points which are completely opposite of each other. These are called the Northern and Southern circumpolar stars. Both star trails are made of different constellations. It makes no sense that the northern night sky reveals another 180 degrees worth of stars "due to perspective" as one moves towards southern latitudes.

* '''Northern stars' trails would appear elliptical:''' Due to the perspective, star trail photography on northern hemisphere would have circular paths only below north pole. The further from the north pole one moves, the more [https://youtu.be/uexZbunD7Jg?feature=shared&t=65 elliptical] the star trails would become. Still, flerfs have zero issue [https://youtu.be/J7RwAcL4Iq0?feature=shared&t=3871 claiming] the stars just rotate on different axis depending on latitude, and provide no explanation how that's possible. Or some, like Eric Dubay lie with [https://youtu.be/V_RceH0-hSk?feature=shared&t=228 images] that have been stretched to make them appear elliptical. For comparison, here are the originals: [https://i0.wp.com/echeng.com/wp-content/uploads/2024/02/echeng120321_23_startrail.jpg?fit=700%2C467&ssl=1 top left], [https://images.slideplayer.com/20/5979770/slides/slide_16.jpg middle left], [https://twanight.org/wp-content/uploads/2022/01/3001252.jpg bottom left], [https://twanight.org/gallery/yukon-aurora-with-star-trails/ top right], [https://www.universetoday.com/wp-content/uploads/2014/05/Polaris-star-trails-July-25_2011S-ANNO.jpg middle right], and [https://www.shutterstock.com/video/clip-7260796-4k-starry-sky-over-reservoir-kremenchuk-mountain bottom right (video, see 00:11)].

* '''Flat Earth south is in all directions''': A person looking at Sigma Octantis from South America would have to be looking in [https://youtu.be/su-fmoZUkF8?feature=shared&t=187 the opposite direction] of a person looking at the same star in Australia.

* '''Southern star trails don't work:''' The flat-earthers claim the reason Sigma Octantis shows up in all directions, is it takes turns in where it appears. As night time moves around the pizza land, the stars follow it. In other words, in the flat Earth model, Sigma Octantis orbits the north pole. This completely debunks the flat Earth model, as the southern sky star trails [https://youtu.be/su-fmoZUkF8?feature=shared&t=107 show Sigma Octantis remains relatively still].

* '''Star trails switch direction on southern hemisphere''': While star trails in the northern hemisphere show that stars [https://youtu.be/su-fmoZUkF8?feature=shared&t=73 revolve around Polaris counterclockwise], in the southern hemisphere they [https://youtu.be/su-fmoZUkF8?feature=shared&t=97 revolve around Sigma Octantis clockwise]. Also, if the camera is looking at the celestial equator, the stars [https://youtu.be/su-fmoZUkF8?feature=shared&t=87 move in parallel straight lines]. All of this can be easily explained by the rotation on a round Earth, but it is impossible in a flat Earth "dome". (Even [[Answers in Genesis]] admits this much!<ref>[https://web.archive.org/web/20210609062841/https://answersingenesis.org/blogs/danny-faulkner/2016/10/12/flat-earth-star-trails/ Flat Earth-Star Trails] by Danny R. Faulkner (October 12, 2016) ''Answers in Genesis'' (archived from June 9, 2021).</ref>)

*'''Equatorial mounts are needed''': Contrary to what flerfs like [https://youtu.be/N9CQPMOzeRs?si=p8lAtHKRQn2xrZFz&t=5017 Dubay quoting William Carpenter] have claimed, astronomers have to compensate for the curvature of the Earth in the form of {{wpl|equatorial mount||s,}} and have done so since the late 1700s. Equatorial mounts are used for {{wpl|polar alignment}} in which the axis of rotation of the telescope is aligned with the axis of rotation of the Earth, and rotated in the opposite direction to eliminate apparent movement. On a flat Earth, the polar axis would always be directly perpendicular to the plane of the planet - but a round Earth requires it to be tilted at an angle equal to the latitude of the observer. See Dave McKeegan's [https://www.youtube.com/watch?v=LHU_6Ot067M video] for more in depth explanation why equatorial mounts make zero sense on a flat Earth.

[[File:New Horizons Proxima Centauri Parallax Animation.gif|thumb|right|Two-frame animation of our nearest star, {{wpl|Proxima_Centauri|Proxima Centauri|,}} taken from the {{wpl|New_Horizons|New Horizons probe|,}} and from Earth, shows parallax visible to the naked eye. A flat Earth would show no parallax so of course flerfs like [https://youtu.be/5WemOn1pqrU?si=gJURY-xNSGy2yrx6&t=97 Dubay] lie about it not being there.]]

* '''Stellar parallax exists''': Over longer time periods astronomers can observe the apparent movement of nearby stars caused by Earth's orbit around the Sun, though it is quite small. Still, '''stellar parallax would not exist at all if Earth was the flat immovable place flerfs claim it is.''' In astronomy, the {{wpl|parsec}} is defined as the distance where a star will appear to move back and forth by one arc-second over the course of a year, meaning they measure the precise differences in angles needed to aim a telescope directly at certain star while Earth is on either side of the Sun during its full orbit (for example aiming on the summer solstice and winter solstice and calculating the parallax based on those minute differences). While light-years are what the public generally thinks in when thinking of astronomical differences are far, far more widely used in popular science publications, parsecs are the preferred unit of distance by astronomers due the ease of making calculations with them, acting as a sort of a metric light-year (coincidentally, the ratio between the length of a foot and meter (1:3.28) is almost the same as between the light-year and parsec (1:3.26)).

=="But Polaris can be seen from the Tropic of Capricorn!"==

[https://www.youtube.com/watch?v=SauZfMS-lZo&t=8847s Cries] Eric Dubay, [https://archive.org/details/1865RowbothamZeteticAstronomy/page/40/mode/2up?q=%22tropic+of+Capricorn%22 parroting Rowbotham's Zetetic Astronomy]. To Quote Astronomy magazine's [https://www.astronomy.com/science/is-polaris-visible-from-the-southern-hemisphere/ article] on the topic:

{{cquote|Although Polaris is also known as the North Star, it doesn’t lie precisely above Earth’s North Pole. If it did, Polaris would have a declination of exactly 90°. Instead, our navigational beacon currently has a declination of 89.34°. The difference, 0.66°, would be Polaris’ peak altitude if viewed '''from the equator''', and the latitude south of the equator from which the star would scrape the horizon — if Earth had no atmosphere. But our blanket of air refracts starlight, causing an object near the horizon to appear higher than it really is. Under typical atmospheric conditions, this adds 0.57° to an object’s altitude, so '''Polaris would barely show up from 1.23° south latitude.'''|||Astronomy Magazine<ref>Astronomy Staff (Dec. 14, 2018). [https://www.astronomy.com/science/is-polaris-visible-from-the-southern-hemisphere/ "Is Polaris visible from the Southern Hemisphere?"]. Via astronomy.com</ref>}}

So Dubay is just blatantly lying. The burden of proof is on him, and he's free to travel to southern hemisphere to make history by being the first one ever to document Polaris from the Tropic of Capricorn.

=="But all stars gradually decline when moving away from the North pole!"==

[[File:Polaris angle2.jpg|thumb|right|The angle at which Polaris at the top of the hemispherical dome will be seen from its edge, is 45°, no matter what the actual size of the dome is. Assuming the Dome is larger than the edge of Ice Wall, will only make Polaris appear even higher.]]

[[File:Polaris altitude.jpg|thumb|right|A screenshot from Dubay's video shows Polaris will be seen at very low altitude when observed at the equator. One thing Dubay forgot: Now Polaris is right above ground.]]

[https://youtu.be/J7RwAcL4Iq0?si=uVQznZpYVwpSgC-P&t=7444 Says] Eric Dubay. Let's see what really happens, first on a hemispherical dome (perfect sphere cut in half), and then a flattened one. In all cases, the observation will be done from the edge of the firmament.

'''Hemispherical dome'''

Let's assume the pizza land's radius, i.e. distance from north pole to firmament is
20,000 km. If Polaris is attached to the firmament, it will be visible at  

[[File:Hemispherical dome polaris angle 20 000 km.svg|475px]] <!-- <math>\theta = tan^{-1} \frac{\text{height of Polaris}}{\text{distance from north pole}} = tan^{-1} \frac{20,000km}{20,000km}= 45^{\circ}</math> --> angle. It will not disappear.

The distance at which Polaris would appear to be at 10° above the horizon, is [[File:Hemispherical dome distance 10 deg.svg|200px]]<!-- <math>d = \frac{20,000}{tan(10^{\circ})} = 113,400km</math> -->

The distance at which Polaris would appear to be at 1 arc-minute above the horizon, is [[File:Hemispherical dome distance 1 arcminute.svg|225px]] <!-- <math>d = \frac{20,000}{tan(\frac{1}{60}^{\circ})} = 68,730,000 km</math> -->

'''Flattened firmament'''

But perhaps God doesn't have to care about structural integrity, and the peak of the firmament with Polaris glued to it, is right above the Sun, at 3,000 miles, or 4,828 km. Now, Polaris will be seen at [[File:Low ceiling dome polaris angle 20 000 km.svg|485px]]<!-- <math>\theta = tan^{-1} \frac{\text{height of Polaris}}{\text{distance from north pole}} = tan^{-1} \frac{4,828km}{20,000km}= 13.63^{\circ}</math> --> angle. It will not disappear.

The distance at which Polaris would appear to be at 10° above the horizon, is [[File:Low ceiling dome distance 10 deg.svg|200px]] <!-- <math>d = \frac{4,828km}{tan(10^{\circ})} = 27,400km</math> -->, which is outside the firmament.

The distance at which Polaris would appear to be at 1 arc-minute above the horizon, is [[File:Low ceiling dome distance 1 arcminute.svg|225px]] <!-- <math>d = \frac{4,828km}{tan(\frac{1}{60}^{\circ})} = 16,600,000 km</math> --> which is 43 times further away than the Moon in the globe model.

If you think this problem can be made to go away, by saying the firmament is much larger, then that only raises polaris, and it should appear higher on all latitudes.

== "But Sigma Octantis can not be seen with publicly available telescopes!" ==

[https://youtu.be/N9CQPMOzeRs?si=RqJodnp9vY4eXo0h&t=3802 Claims] Eric Dubay. {{wpl|Sigma_Octantis|Sigma Octantis}} has apparent magnitude of 5.47. The {{wpl|Limiting_magnitude|}} of stars in dark suburban areas is about 5. Thus, Sigma Octantis is barely visible with naked eye. As explained [https://www.youtube.com/watch?v=fNljq7o1ZtY here], the star can be photographed with roughly 30 second exposure time. Also, telescopes not only zoom in, they also gather more light than the human eye, making objects brighter.<ref group='note'>If lenses did not collect and focus more light energy, {{wpl|Burning_glass|burning glasses}} wouldn't be a thing.</ref>  Thus, Sigma Octantis that's already barely visible with our tiny pupils, absolutely can be seen with a store bought telescope.

== See also ==

* [[Flat_Earth|Flat Earth]]

Flat Earth debunks

* [[Flat_Earth_debunks_-_The_Earth|The Earth]]

* [[Flat_Earth_debunks_-_The_Moon|The Moon]]

* [[Flat_Earth_debunks_-_The_Sun|The Sun]]
* '''[[Flat_Earth_debunks_-_Celestial_mechanics|Celestial mechanics]]'''
* [[Flat_Earth_debunks_-_Celestial_objects|Celestial objects]]
* [[Flat_Earth_debunks_-_Astronautics|Astronautics]]
* [[Flat_Earth_debunks_-_Astrophotography|Astrophotography]]
* [[Flat_Earth_debunks_-_The_conspiracy|The conspiracy]]

==Notes==
{{reflist|group=note}}

==References==
{{reflist|2|80%}}

[[Category:Anti-intellectualism]]
[[Category:Conspiracy theories]]
[[Category:Denialism]]
[[Category:Flat Earth]]
[[Category:Pseudoscience]]
[[Category:Pseudoastronomy]]

Categories: Anti-intellectualism, Conspiracy theories, Denialism, Flat Earth, Pseudoscience, Pseudoastronomy