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The Planets Today

theplanetstoday.com

94 pointshyperific33 comments

Don't miss the button in the lower right to switch between desktop and mobile view, I almost did.

"If you have our desktop version enabled on your computer, then the application shown above plots the position of the Earth and planets using data from this NASA's JPL website and is accurate between 3000 BCE and 3000 CE. If you have our mobile version enabled then we'll be showing you a simpler view of the solar system showing you the current planetary positions with the option of moving up to 30 days forwards or backwards."

970 years from now someone is going to get rich selling an entire series of books about the upcoming apocalypse, predicted by the ancient NASA* calendar suddenly ending.

* which will most likely be interpreted as a fertility cult because of all the phallic monuments.

This all but confirms that the Mayans had a robust space program going.

It's well known that there's an undiscovered functional Mayan space ship under Central Park: https://futurama.fandom.com/wiki/A_Farewell_to_Arms

Also click on "Luna" on the bottom left to see a view of plants

I like this. It really helps illustrate that how long it takes to get to Mars can vary hugely depending on when you leave Earth.

My kids learned in school (during the 5 minutes of the year they spent talking about the solar system) that Venus is closer to Earth than Mars, but I had to use a diagram like this to explain that that's only sometimes true

kind of limiting that you can only go back and forward in time one month though. I would love a slider, a play button

The free (FOSS, I believe) program Celestia is excellent for showing kids that kind of thing.

It’s also lua-scriptable. I once created a “tour of the solar system” script that worked like a presentation (hit a button to advance to the next view) for my wife to use in her classroom, in an afternoon, never having scripted the program or written Lua before. Did a top-down view with orbital tracks, zoomed to planets, did side-by-side size comparisons, all kinds of stuff. Not hard to use, very cool. Or you can just click around the UI and use keyboard shortcuts to demonstrate quite a bit of stuff.

If you're on iOS, there's an app called Solar Walk that might be fun to play around with.

If you want orbits and a slider, there's <https://www.pbslearningmedia.org/resource/buac20-sci-ess-wwt...>

Though it doesn't show today, this 3D model of the solar system is great

https://codepen.io/juliangarnier/pen/krNqZO

Tangentally, I came across this preprint today about sensible definitions for planets, as IAU doesn't actually call exoplanets "planets", and there's some unclarity re hydrostatic equilibrium ("how round") and especially the "clearing the path" / orbital dominance

Quantitative Criteria for Defining Planets (UCLA) https://arxiv.org/abs/2407.07590

I had to do a double take on this minor detail —

The current date is expressed as:

     12:07:2024 AD

I don’t think I’ve ever seen colons used as a date part separator, only as a time part separator (and they tend toward ambiguity even there).

And “AD” is generally superseded by “CE” now, isn’t it?

(I ruin everything by caring about the wrong details! It’s a great game. Try it! You’ll hate it.)

The orbits look perfectly circular. Is this a simplification, or are the elipses so mild that they look like circles at that scale?

It must be a simplification, for example Pluto's orbit is so eccentric that it's sometimes closer than Neptune

Except for Mercury (eccentricity[0]: 0.2056) and the displayed transneptunian objects Eris (0.4407(!)), Pluto (0.2488), Haumea (0.1887) and Makemake (0.1559) all other planets (including the dwarf planet Ceres (0.0758)) are pretty accurate.

Current orbital eccentricites for our plantes in ascending order:

[0.00002 (Triton)]

0.0068 (Venus)

0.0086 (Neptune)

0.0167 (Earth)

0.0472 (Uranus)

0.0541 (Saturn)

0.0934 (Mars)

[0.9951 (parabolic) (Comet Hale-Bopp)]

So, the planets eccentricities (except for Mercury) are within one order of magnitude (0.01 and 0.1) nearly circular.

[0]https://en.wikipedia.org/wiki/Orbital_eccentricity

Click "To Scale View" in the upper left, then click on the concentric blue circles in the upper right of the main diagram to show inner planets, outer planets, or all planetoids including Eris.

Also check out the Geocentric view for the earthbound perspective.

An honorable mention: https://celestiaproject.space

This but in 3D and adjustable for any date. Plus lots of fun stuff like popular culture sci fi spacecraft.

I’ve seen so many times this 2D representation of the solar system and I felt somehow shocked when I saw a Youtube video supposedly showing how the planets actually orbit around the sun, and how the sun orbits the center of our galaxy. Basically, the sun is moving and the planets orbiting around it form some sort of vortex. If you look at the whole thing as if you were in front of the vortex (or behind), you would see the 2D representation.

I don’t know either if that’s what happens in reality but this 2D representation is getting old I guess.

I've seen that too when it was making the rounds. It's certainly interesting in that it opens your mind to the concept of reference frames. That said, I don't think the 2D representation is really all that inaccurate (and certainly that "vortex" animation isn't particularly MORE accurate either).

That's the thing about reference frames. There is no absolute and there can be multiple that are equally valid. Frankly, using the sun as our reference frame makes perfect sense to me.

When you're trying to visualize a car trip on a map from one city to another, is it really useful to visualize the car, the city, and the planet all spinning around, moving through space in the same kind of vortex?

It depends on your frame of reference - that video is true for a frame of reference which is the center of the galaxy. This representation is with the sun as the frame of reference. From that point of view it is the galaxy that is moving with respect to the sun and the planets.

The "vortex model" that went viral something like 10 years ago was more or less immediately debunked by scientific news outlets. It is beautifully made and intriguing but unfortunately not correct.

See more: https://www.universetoday.com/107322/is-the-solar-system-rea...

The website design reminds me of my initial forays into website creation in the early 2000s using Dreamweaver.

The code of the website if from that era, and the interactive element in the center was written in flash.

You don't need flash installed in the browser to view it because flash projects can be emulated by js frameworks and they can also be "compiled" to web.

I heard from some young people the 2000s aesthetic is "in" right now.

Sol and Luna. Nice to see sensible names for these.

Sol and Luna are technically "incorrect" names for The Sun and The Moon, as per the IAU. (Notably, so is "Terra" for Earth. Earth is Earth, it already has a proper name)

That is not to say I think they're un-sensible. I think it would be a great idea for the IAU to adopt them, as "Sun" and "Moon" are already generic terms from the reference of other planets/solar systems.

IAU is not a sensible organization. See: Pluto and the dwarf planet category.

It doesn't make sense to call Pluto a planet.

In fact, if we needed to change it's classification it would make more sense to call it a binary dwarf planet or a binary planet than it would to call it a planet again.

An indicator of which way the planets are moving and more importantly spinning would be nice.

I have bookmarked it so I can see about where the planets are. Thank you.

Its a great site. Really enjoyed playing with that.

Now back to work.. :(

wow now i understand the mandala representation in hindu cosmoology, the movements of the planets and the whole cosmos in lines of their paths

Moon not Luna

"Moon" (capitalized) is too confusing when talking about moons. It's easier to give it its own designation.

confusing for who?

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