Astronomers Develop First 3-D Map of Milky Way August 1, 2019

[Judi Lynn]

August 1, 2019



Comparison of simulation of three main star forming episodes in the spiral arms with the currently observed Cepheid variables. Oldest stars (red) are 400 million years old and the youngest (blue) are 30 million years old. Top view of the Milky Way, simulations are shown in the left panel, observations – in the right panel. (J. Skowron / OGLE / Astronomical Observatory, University of Warsaw)

(CN) – The Milky Way galaxy is home to countless stars, planets, and other celestial objects. Currently, scientists’ knowledge of its shape is based on what is known about other galaxies and models of our own solar system – but it is not the whole picture.

Astronomers Dorota Skowron and her colleagues from the University of Warsaw used a much more accurate means of gathering this information. In their study published Thursday in the journal Science, they showed that by measuring the distance between classical Cepheid variable stars within the galaxy, they could develop a three-dimensional map of the Milky Way in unprecedented detail.

Cepheid variables are different from ordinary stars, and have been used in the past as markers to measure distances of up to millions of light-years. The Hubble Telescope recently used these stars to determine the distance to a galaxy in the Virgo cluster, 56 million light-years from Earth. The Cepheid variable stars are useful because they pulsate at a constant rate of luminosity similar to a lighthouse, allowing astronomers to determine their distance from another object.

Thanks to a project named the Optical Gravitational Lensing Experiment (OGLE), scientists have identified more than double the number of classical Cepheid variables previously known. Skowron and her colleagues charted the distances of more than 2,400 Cepheid variables and determined their coordinates relative to the sun. Using this mapping approach, they re-examined what is known about the Milky Way’s physical features.

More:
https://www.courthousenews.com/astronomers-develop-first-3-d-map-of-milky-way/

[PoindexterOglethorpe]

1. How cool!

I have just sent a text to My Son the Astronomer about this. Hopefully we'll discuss it later on today.

[ThoughtCriminal]

2. Another discovery

[nitpicker]

3. From the BBC

https://www.bbc.com/news/world-us-canada-49182184

Milky Way galaxy is warped and twisted, not flat

By Pallab Ghosh
Science correspondent, BBC News

1 August 2019


Our galaxy, the Milky Way, is "warped and twisted" and not flat as previously thought, new research shows. Analysis of the brightest stars in the galaxy shows that they do not lie on a flat plane as shown in academic texts and popular science books.

Astronomers from Warsaw University speculate that it might have been bent out of shape by past interactions with nearby galaxies.

The new three dimensional map has been published in the journal Science.

The popular picture of the Milky Way as a flat disc is based on the observation of 2.5 million stars out of a possible 2.5 billion. The artists' impressions are therefore rough approximations of the truer shape of our galaxy, according to Dr Dorota Skowron of Warsaw University.

"The internal structure and history of the Milky Way is still far from being understood, in part because it is extremely difficult to measure distances to stars at the outer regions of our galaxy," she said.
(snip)