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Comment by rdiddly | Hacker News Reader

I just want to know where it is, jeez. Map of the galaxy please! (Assuming it's in this galaxy.)

After a extensive search I give up, but I found some data that may be useful.

As another commenter found, these star and planets are 650 light years away, that's very close for a star, very near us in the Milky Way.

This is a map of our neighborhood in a range of 5000 light year: http://www.atlasoftheuniverse.com/5000lys.html

For comparison, Polaris is 323–433 ly away and Rigel is 860 ± 80 ly away in the opposite direction. So 650 ly is a distance in between, but I still can't understand in which direction is this.

In a map of the full galaxy (x10 zoom out) http://www.atlasoftheuniverse.com/galaxy.html these star and planets are only a few pixels away from the Sun.

More data, in case someone know how to use an astronomy program to make a nice graphic: http://simbad.u-strasbg.fr/simbad/sim-id?Ident=HD+195689

> So 650 ly is a distance in between, but I still can't understand in which direction is this.

The SIMBAD link you gave gives you the RA and Dec (Right Ascention and Declination) which gives you a precise co-ordinate for where in the sky the object is. It's a bit difficult to wrap your head around the co-ordinate system but if you think about it hard enough you could translate to a map of the galaxy.

To be frank, most researchers don't look at maps of the galaxy for analysis, in general you're looking at things from the perspective of Earth.

Does the article specify the planet's distance from Earth? I can't seem to find this rather fundamental information.

Seems like the article indeed forgets to mention the distance. I guess the nature article[0] has all the information, but since I can't access that one right now I also found a Washington Post article[1], according to which the distance from Earth is about 650 light-years.

[0]https://www.nature.com/nature/journal/vaop/ncurrent/full/nat...

[1]https://www.washingtonpost.com/news/speaking-of-science/wp/2...

It doesn't but the paper's abstract mentions the HD identifier, so you can look it up on SIMBAD[1] to get the parallax. While parallaxes aren't the best measure of distance (they really aren't very good at all) you can get an okay estimation by taking [d = 1/p] where d is in parsecs and p is in arcseconds. Saving you the math, it's about ~188 ±20 parsecs (~564±60 ly).

[1]: http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+195689&...

The nature article[1] mentions in the abstract that the identifier for KELP-9 (the host star) in the Henry Draper catalog is HD 195689. Here's the information about it from SIMBAD[2]. It also appears to have been referenced in 6 other papers, so I presume that such information already exists about it.

[1]: https://www.nature.com/nature/journal/vaop/ncurrent/full/nat... [2]: http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+195689&...

Any talk of a confirmed exoplanet will be in our galaxy.

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