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Posted on 03/09/2019 10:18:12 AM PST by ETL
Scientists have finally been able to accurately calculate the weight of the Milky Way, overcoming the difficult hurdle of measuring dark matter, the European Space Agency (ESA) announced Thursday.
After years of struggling to estimate the size of our galaxy, astronomers with NASA and the ESA used data from the Hubble Space Telescope and the ESA’s Gaia mission to determine the Milky Way weighs about 1.5 trillion solar masses within a radius of 129,000 light years from the center.
Because dark matter makes up about 90 percent of the galaxy, estimates of the Milky Way’s weight have differed widely in the past.
Previous measurements ranged from 500 billion to 3 trillion times the mass of the Sun.
"We just can't detect dark matter directly," Laura Watkins, of the European Southern Observatory in Germany who led the team’s analysis, said in a statement.
"That's what leads to the present uncertainty in the Milky Way's mass – you can't measure accurately what you can't see."
Because dark matter is so difficult to calculate, Watkins and her team measured the velocities of dense star clusters, called globular clusters, that orbit the galaxy’s spiral disc.
They used data from Gaia, the ESA’s space observatory, to measure globular clusters as far as 65,000 light-years away from Earth and data from the Hubble Space Telescope — a project shared by NASA and the ESA — to measure globular clusters as far as 130,000 light-years away from Earth.
(Excerpt) Read more at foxnews.com ...
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Orion asks, "Does this belt make me look fat?
-PJ
LOL. GREAT catch. Objects in space have a fixed mass but their weight varies with gravitational attraction, i.e. distance to other objects. You get a gold star for catching that right off the bat.
#2 The Romulans and Klingons disagree.
Q says Earthlings no not what they say.
It can be. To within 2 significant digits. Of course, they don't mention error bars that are probably bigger than their entire estimate.
If I recall correctly though, mass will increase with speed. Relatively anyways.
I can.
The Milky Way weighs nothing.
Sure--it's got mass. But there is no weight.
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