11 Fascinating Facts About Our Milky Way Galaxy.

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Credit: ESA/NASA/JPL-Caltech
▼ How much do you know about the city you live in? Sure, you've got your favorite restaurants and the best way to avoid traffic during rush hour, but it's unlikely you know the details of every urban nook and cranny. The same goes for the galaxy you live in, the Milky Way.
Our celestial home is an awe-inspiring place full of stars, supernovas, nebulas, energy and dark matter, but many aspects of it remain mysterious, even to scientists. For those seeking to better know their own place in the universe, here are 11 enlightening facts about the Milky Way.
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Credit: Juan Carlos Muñoz/ESO
Small galaxies orbit the Milky Way and sometimes crash into it
When Portuguese explorer Ferdinand Magellan sailed through the Southern Hemisphere in the 16th century, he and his crew were among the first Europeans to report on circular clusters of stars in the night sky, according to the European Southern Observatory. These clusters are actually small galaxies that orbit our Milky Way like planets around a star, and they have been named the Small and Large Magellanic clouds. Many such dwarf galaxies orbit ours — and sometimes they get eaten by our massive Milky Way. Earlier this year, astronomers used new data from the Gaia satellite that showed millions of stars in our galaxy moving in similar narrow, "needle-like" orbits, suggesting they all originated from an earlier dwarf galaxy dubbed "the Gaia  Sausage," as Live Science reported at the time.
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Credit: Two Micron All-Sky Survey
We're not sure exactly how many stars are in the Milky Way
Counting stars is a tedious business. Even astronomers argue over the best way to do it. Their telescopes see only the brightest stars in our galaxy, and many are hidden by obscuring gas and dust. One technique to estimate the stellar population of the Milky Way is to look at how fast stars are orbiting within it, which gives an indication of the gravitational tug, and therefore the mass, of the galaxy. Divide the galactic mass by the average size of a star and you should have your answer. But as David Kornreich, an astronomer at Ithaca College in New York, told Live Science's sister site Space.com, these numbers are all approximations. Stars vary widely in size, and many assumptions go into estimating the number of stars residing in the Milky Way. The European Space Agency's Gaia satellite has mapped the location of 1 billion stars in our galaxy, and its scientists believe this represents 1 percent of the total, so perhaps the Milky Way contains  about 100 billion stars.
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Credit: Shutterstock
Nobody knows how much the Milky Way weighs
On a related note, astronomers are still unsure exactly how much our galaxy weighs, with estimates ranging from 700 billion to 2 trillion times the mass of our sun. Getting a better grasp is no easy task. Most of the Milky Way's mass — perhaps 85 percent — is in the form of dark matter, which gives off no light and so is impossible to directly observe, according to astronomer Ekta Patel of the University of Arizona in Tucson. Her recent study looked at how strongly our galaxy's humongous mass gravitationally tugs on smaller galaxies orbiting it and updated the estimate of the Milky Way's mass to 960 billion times the mass of the sun, Live Science previously reported.
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Credit: Springel et al./Virgo Consortium
The Milky Way is probably in a big, empty spot in the universe
Several studies have indicated that the Milky Way and its neighbors are living out in the boonies of the cosmos. From afar, the large-scale structure of the universe looks like a colossal cosmic web, with string-like filaments connecting dense regions separated by enormous, mostly empty voids. The emphasis in that last sentence should be on "mostly empty," since our own galactic abode seems to be an inhabitant of the Keenan, Barger and Cowie (KBC) Void, named after three astronomers who identified it in a  2013 studyin The Astrophysical Journal. Last year, a separate team looked at the motion of galaxies in the cosmic web to provide additional confirmation that we're floating in  one of the big, empty areas, Live Science previously reported.
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