Re: APOD: 4000 Exoplanets (2022 Aug 14)
Posted: Mon Aug 15, 2022 8:25 pm
Great point. I keep forgetting things like that.
APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
Great point. I keep forgetting things like that.
And I only noticed the Kepler transit method discoveries' cumulative shape in the interactive video after you pointed it out!MarkBour wrote: ↑Mon Aug 15, 2022 8:20 pmThanks. With the explanation, it is better. I thought that a compendium of exoplanets might tend to align with the Milky Way, but I think this video shows that our discoveries so far are in our local stellar neighborhood and are all over the sky, so the Milky Way at this time is not especially relevant to the image. In that vein, the plot of the Kepler-found planets in lavender is interesting. Basically, it is a solid shape of a plus sign ("+"). It is not showing us where more exoplanets are, it is showing us where we looked. Indeed, it shows us the shape of Kepler's CCD sensor array. It found planets everywhere.alter-ego wrote: ↑Mon Aug 15, 2022 4:31 am Basically, the entire 360° view of the MW is presented in cylindrical coordinates. Instead of mapping the MW center to image center, the first 2 exoplanets were centered. Doing so results in the sine-wave-like distortion of the MW in the image. Other mappings would distort the MW band differently. Common mappings (stereographic and fisheye) distort the WM to an off-centered circle or oval which doesn't fill the image field as well in my opinion. I personally like the APOD symmetrical MW presentation. Interesting the Earh is also added to the image.
Ah, I hadn't noticed, but yes, the circles do warp as you move around. And I like it better, too.johnnydeep wrote: ↑Mon Aug 15, 2022 1:53 pm
Thanks. I hadn't bothered to watch the "shown compressed" video, and even when I did just now I didn't realize until the second watch that you can use the mouse to change the view and thereby "look" around at the entire sky! And when doing so, you can clearly see that the eccentricity of the circles changes dynamically as you pan the sky. Thus, they mean nothing in particular with regard to the exoplanets shown. And in a difference of opinion with alter-ego, I GREATLY prefer that interactive video to the one in the APOD!