Good drawing of Earth's orbit for model? Possibly vector file?

[LightningInAJar]

TL;DR

Does anyone know where a 2D drawing of the earth's orbit can be found?

I would like to create a 3D printable model of the earth's orbit around the sun and slice it into the months of the year. So basically a calendar. Except I wanted to add heights for relative local weather conditions for a given year. Does anyone know the best way to draw our orbit?

 

[renormalize]

TL;DR: Does anyone know where a 2D drawing of the earth's orbit can be found?

How precise does the drawing have to be? According to https://en.wikipedia.org/wiki/Apsis, the Earth's orbital radius at aphelion vs. perihelion in AU is $1\pm0.0167$. That's less than 2% deviation from a perfect circle. Is depicting Earth's orbit as a simple circle close enough for your graphical purposes?

 

[Filip Larsen]

Except I wanted to add heights for relative local weather conditions for a given year.

The seasonal variations in weather on Earth are primarily driven by the tilt of the Earths spin axis relative its orbit around the Sun, and to a much lesser degree by the (small) variation in distance to the Sun. In this context what do you then mean by "height"?

 

[LightningInAJar]

How precise does the drawing have to be? According to https://en.wikipedia.org/wiki/Apsis, the Earth's orbital radius at aphelion vs. perihelion in AU is $1\pm0.0167$. That's less than 2% deviation from a perfect circle. Is depicting Earth's orbit as a simple circle close enough for your graphical purposes?

I want to be precise even if it might not be noticeable with a 3D printer's level of detail. Would it not be visually noticeable to see the Earth closer to the sun in the N hemis winter?

 

[LightningInAJar]

The seasonal variations in weather on Earth are primarily driven by the tilt of the Earths spin axis relative its orbit around the Sun, and to a much lesser degree by the (small) variation in distance to the Sun. In this context what do you then mean by "height"?

I mean there would be a base thickness of the model in general and for example increase thickness in different pie sections based on say average temp or rain fall.

 

[FactChecker]

If you are talking about average temp or rain fall in a particular location, the tilt of the Earth's axis is much more significant than the shape of the orbit. If you are talking about global surface temperature, you should be aware that there is a great deal of random behavior in that data. I doubt that you will detect the effect of the orbit shape without an enormous amount of accurate data.

 

[renormalize]

I want to be precise even if it might not be noticeable with a 3D printer's level of detail. Would it not be visually noticeable to see the Earth closer to the sun in the N hemis winter?

Suppose you draw the orbit as a 200mm (approximately 8 inch) diameter circle centered on the sun. Then the actual position of the Earth in northern winter would be shifted by less than 2mm to the inside of the circle. How visually noticeable do you consider that?

 

[Filip Larsen]

How visually noticeable do you consider that?

Wikipedia's page on Earth's orbit has a nice drawing that might aide in that assessment:
https://en.wikipedia.org/wiki/Earth's_orbit#/media/File:EarthsOrbit_en.png

 

[LightningInAJar]

If you are talking about average temp or rain fall in a particular location, the tilt of the Earth's axis is much more significant than the shape of the orbit. If you are talking about global surface temperature, you should be aware that there is a great deal of random behavior in that data. I doubt that you will detect the effect of the orbit shape without an enormous amount of accurate data.

I wanted to make the model just to give a visual of the weather of a given year. The cause of weather change doesn't matter to me. Just a freeze frame of a year.

 

[FactChecker]

I wanted to make the model just to give a visual of the weather of a given year. The cause of weather change doesn't matter to me. Just a freeze frame of a year.

That's an important clarification.

 

[LightningInAJar]

That's an important clarification.

The Earth's orbit is a perfect eclipse? No weird warps at either end? I still want to be kind of authentic with it. And how does one identify locations along the path in reference to a day of the year for a given year?

 

[renormalize]

The Earth's orbit is a perfect eclipse? No weird warps at either end?

The Earth's orbit is an almost-circular ellipse.

 

[FactChecker]

The Earth's orbit is a perfect eclipse?

"Perfect" is a very strong requirement. The Earth/Moon combination is nearly perfect. The Earth alone will be influenced a tiny bit by the Moon.

No weird warps at either end?

No. Nothing in physics is there to give it "weird warps".

I still want to be kind of authentic with it. And how does one identify locations along the path in reference to a day of the year for a given year?

@Filip Larsen 's post #8 should help you in that.

 

[phyzguy]

@LightningInAJar , doesn't @Filip Larsen 's post #8 give you everything you've asked for?

 

[LightningInAJar]

@LightningInAJar , doesn't @Filip Larsen 's post #8 give you everything you've asked for?

Do I need to convert degrees into days and align the particular years first day of spring with the vernal equinox?

 

[robphy]

The seasonal variations in weather on Earth are primarily driven by the tilt of the Earths spin axis relative its orbit around the Sun, and to a much lesser degree by the (small) variation in distance to the Sun. In this context what do you then mean by "height"?

It's crude and not-to-scale in space, but this might be qualitatively helpful:
https://glowscript.org/#/user/Rob_Salgado/folder/My_Programs/program/SunshineOnTheEarth/edit

You can edit the value of the latitude for different places on Earth.

 

[Filip Larsen]

Do I need to convert degrees into days and align the particular years first day of spring with the vernal equinox?

The diagram in #8 show the yellow orbit of Earth with the Sun fixed at the filled yellow dot near the center. The white circle is centered on the Sun with a (constant) radius that reflect the mean (average) Sun/Earth distance, thus making the annual variation of the Sun/Earth distance much easier to spot.

The month division along the orbit show where Earth is during that month, relative to the direction in space called the vernal equinox, which again is defined as the direction in space as seen from Earth towards the Sun at the time where the Sun passes the Earth equator towards the north. This direction acts as a reference direction when describing other Sun-orbiting objects relative to the Ecliptica (Earth orbit plane).

So, for example, around July 1st the Sun will have a longitude of around 100°. Note that the diagram arbitrarily has chosen 0° to be towards the right. You can rotate the whole diagram as you like without changing its meaning.

I am still not sure exactly what aspects you would like your model to reflect, but if you want it to show the "reason" for seasonal variations in 3D, so to speak I still say you probably want to somehow indicate the orientation of the equator along the orbit, e.g. something like illustrated below. Here the red ellipse corresponds to the yellow ellipse in the other drawing and you can see the Earth is tilted (around 23.4°, called the obliquity of the Ecliptic) and the seasons on the two hemispheres can be "deduced" from the amount of Sunlight they receive at the four shown positions.

https://en.wikipedia.org/wiki/Earth's_orbit#/media/File:North_season.jpg:

 

[LightningInAJar]

The diagram in #8 show the yellow orbit of Earth with the Sun fixed at the filled yellow dot near the center. The white circle is centered on the Sun with a (constant) radius that reflect the mean (average) Sun/Earth distance, thus making the annual variation of the Sun/Earth distance much easier to spot.

The month division along the orbit show where Earth is during that month, relative to the direction in space called the vernal equinox, which again is defined as the direction in space as seen from Earth towards the Sun at the time where the Sun passes the Earth equator towards the north. This direction acts as a reference direction when describing other Sun-orbiting objects relative to the Ecliptica (Earth orbit plane).

So, for example, around July 1st the Sun will have a longitude of around 100°. Note that the diagram arbitrarily has chosen 0° to be towards the right. You can rotate the whole diagram as you like without changing its meaning.

I am still not sure exactly what aspects you would like your model to reflect, but if you want it to show the "reason" for seasonal variations in 3D, so to speak I still say you probably want to somehow indicate the orientation of the equator along the orbit, e.g. something like illustrated below. Here the red ellipse corresponds to the yellow ellipse in the other drawing and you can see the Earth is tilted (around 23.4°, called the obliquity of the Ecliptic) and the seasons on the two hemispheres can be "deduced" from the amount of Sunlight they receive at the four shown positions.

https://en.wikipedia.org/wiki/Earth's_orbit#/media/File:North_season.jpg:
View attachment 372660

I actually don't care the cause of weather changes. I just want to represent the weather conditions historically for a given year. Temps, rain fall, snow fall, etc. Basically a round graph for a duration.

 

[phyzguy]

I actually don't care the cause of weather changes. I just want to represent the weather conditions historically for a given year. Temps, rain fall, snow fall, etc. Basically a round graph for a duration.

So you have everything you need, right?

 

[LightningInAJar]

So you have everything you need, right?

I believe so. I think in my design software I can just create a regular polygon with a multiple of 12 sides (enough to make it smooth) so I can find 1/12 points, and apply a stretch so it becomes elliptical.

 

[renormalize]

I've thought a bit more about it and decided to use Mathematica to investigate your question, as I understand it. Since you haven't specified the location of the weather data you want to use, I arbitrarily chose to download (from NOAA) 2025 daily maximum temperatures for Seattle, Washington, USA, along with daily Earth-Sun distances (from NASA), and plotted the data:

Clearly the daily temperatures are indeed roughly correlated with the Earth-Sun distances. So let's now convert the data to a polar form. From the daily radii, I used the well-known equation for elliptical orbits to extract the polar angle of the position of the Earth relative to the Sun for each day in 2025, plotted below as 365 blue dots:

Based on my interpretation of your question, I also show Seattle's maximum temperature day-by-day as a separate red "height" plot around the inside of the orbit. My comments follow:

• Perihelion (minimum Earth-Sun distance, slightly less than $1\text{AU}$) occurs on Day 3.
• Aphelion (maximum Earth-Sun distance, slightly more than $1\text{AU}$) occurs on Day 184.
• But visually, the Earth's elliptical orbit is almost indistinguishable from a perfect circle, leading me to question whether it's really worth the bother to plot the actual ellipse, as I have done above.
• And in my view, the patterns of daily distances and temperatures are better conveyed by the first two simple rectangular plots instead of the polar plot.

But perhaps I am not the intended audience for what you seek to accomplish.

 

[FactChecker]

IMO, the best thing about @Filip Larsen 's Post#8 is that it emphasizes the axis tilt toward the Sun by indicating degrees off of a vernal equinox. For a given location on Earth it might be interesting to graph the subject of interest versus the angular tilt of the (normal to the) Earth surface away from the Sun.

 

[Filip Larsen]

Clearly the daily temperatures are indeed roughly correlated with the Earth-Sun distances.

While it is not incorrect to say the two statistically roughly correlate it is also a misleading statement since it is a coincidental and inverse correlation (and we know how the average lay-person is prone to confuse correlation with causation). It is a bit like saying that rain correlate with western wind direction (which it does in my country) and then say nothing about how rain much better correlates with the presence of clouds.

 

[FactChecker]

That is not the form of the logical "cause-effect" correlation you should be looking for. (Notice that the correlation is the opposite of what you were expecting. the temperature is greatest when the distance is greatest.)

distances (from NASA), and plotted the data:

Clearly the daily temperatures are indeed roughly correlated with the Earth-Sun distances.

Remember that when the heat from the sun is highest, the Earth temperature will increase the most, but not be the highest. It will continue to increase more although the increases will be smaller.
You should be looking for a "time-lagged" correlation like this, where the peak effect is 1/4th of a cycle later than the peak of the cause:

You will find that "cause-effect" correlation if you look at a local temperature versus the angle between the normal to the Earth surface and the Sun direction. The hottest days of the summer are months AFTER the longest days of the year. With some work, you can get that for a particular Earth location from the information in @Filip Larsen 's post#8.

ADDED: If you still want to see the local effect of the shape of the orbit, you should first remove the larger effect of the tilt of the Earth's axis. In both cases, you should look for a highest temperature that is 1/4th of a yearly cycle (3 months) later than the peak causal effect.

ADDED2: If you are interested in other effects that are directly caused by increased temperatures, you might expect a further delay. Suppose you are interested in the height of crops. The situation might be: cycleOfTiltTowardSun => pi/4 delay => cycleOfLocalTemp => pi/4 delay => cycleOfCropHeight
That might put it at the polar opposite of what you expected.

 

[FactChecker]

https://en.wikipedia.org/wiki/Earth's_orbit#/media/File:North_season.jpg:
View attachment 372660

I might be worth pointing out here that this effect is zero on the Equator. If @LightningInAJar is interested in seeing how the distance to the Sun correlates to something, he should pick a location on the Equator.