Other view layers for lay viewers

I always have so many questions when using this amazing resource. They’re things that people with little subject matter knowledge have but help increase our understanding.

“How far?”
A click option that would tell me how far away a selected object is in light-year terms. I know this probably can be done in other ways, but I’m thinking of something pretty straightforward.

“For scale”
I often wonder: how big is this X object compared to the Milkway Way? So, why not have a toggleable layer with more commonly understood objects – our sun, the milky way, the “largest object in the survey” can be overlayed at the same scale next to the object one is viewing.

“Library of biggest, oldest, and weirdest”
How about a panel with links to lots of objects of interest and extremes:
the biggest object,
the most massive object,
the farthest object,
the closest spot,
the reddest object,
the object with the most objects nearby,
radiation hotspots,
known events,
busy regions with the most galaxies per square measure space,
a sublibrary of unusual/unique/unidentified objects that raise interest, etc.


Thanks for the suggestions. Thing is, this project has ~ 0 staff; it’s basically my side project, and if anyone were paying me to add stuff to it, it would be directed toward the scientists on the DESI (desi.lbl.gov) project that supports it.

Now, other larger efforts like the Sloan Digital Sky Survey have produced huge volumes of educational resources; it’s definitely worth checking out their stuff. And GalaxyZoo also has good resources.

Some specifics:
“How far” is actually an incredibly difficult and controversial question in astronomy. For the nearest stars, we (the Gaia satellite, that is) can measure parallaxes and infer real distances. But for essentially everything else, all we can do is measure their redshift [well, okay, see ‘cosmic distance ladder’ for a couple other handles]. Based on the Hubble diagram, we know that on average a galaxy with a given redshift is a given distance away from us… sort of. Distances over cosmological scales are actually really weird; the distance between things (which you can define in like 3 or 4 different ways) is the result of complicated math on a parameterized cosmological model. For this reason, astronomers usually just talk in redshifts.

Plus, we only have redshifts for a tiny fraction of the galaxies and quasars – mostly from the Sloan Digital Sky Survey. It’s a few million redshifts, out of ~2 billion objects we detect. The DESI survey will increase that by x10, but that’s still at most a couple percent of objects.

For very similar reasons (is it big and far away, or small and nearby?), actual sizes of things are hard to know also!



Thanks, Dustin. It’s a wonderful piece of work. Kudos to you.

Is there one galaxy you could link me to that I could use to imagine what the milky way would look like from the same relative perspective? Size, shape, etc?

Well, the Wikipedia page on the Milky Way suggests that UGC 12158 might look similar to the Milky Way –

(with a green cosmic ray, and some weird magenta star neighbors!)

They also list NGC 2336:

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