As anyone who has been paying attention knows, Edwin Hubble's discovery of the "standard candles" of Cepheid variable stars expanded our universe by magnitudes. Prior to Hubble, "nebulae" that were galaxies, like the Andromeda Nebula, were thought to be within our local neighborhood. But now we know, etc., etc..
But now, we have a new model of our own galaxy (γαλαξίας in Greek: The myth is that somehow Heracles managed to be suckling at the breast of Hera, who when she realized who the infant was, ripped him from her breast and spewed milk across the heavens, the Milky Way), 3D-imaged with Cepheid variables. Article is at Science Mag[$], as well as elsewhere.
Cepheids help to map the Galaxy
Cepheid variable stars pulsate, which allows their distances to be determined from the periodic variations in brightness. Skowron et al. constructed a catalog of thousands of Cepheids covering a large fraction of the Milky Way. They combined optical and infrared data to determine the stars' pulsation periods and mapped the distribution of Cepheids and the associated young stellar populations across the Galaxy. Their three-dimensional map demonstrates the warping of the Milky Way's disc. A simple model of star formation in the spiral arms reproduced the positions and ages of the Cepheid population.
Science, this issue p. 478[$].
Science 02 Aug 2019:
Vol. 365, Issue 6452, pp. 478-482
DOI: 10.1126/science.aau3181[$]
Also at Popular Science.
(Score: 2) by takyon on Friday August 02 2019, @01:00PM
Follow up to this article [soylentnews.org].
We haven't actually seen all of the stars in the Milky Way in great detail. The Gaia [wikipedia.org] mission will help fill in the gaps by characterizing around 1 billion stars. LSST [wikipedia.org] will also help, especially with finding the dimmer objects, such as red and brown dwarfs, and anything near the center of the Milky Way:
https://arxiv.org/pdf/1708.04058.pdf [arxiv.org]
But brighter objects could be observed without impacting the LSST's main science goals:
Some future follow-up missions will be needed before we know where 100 billion to 1 trillion Milky Way objects are.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]