On this day, the day filled with teddy bears, chocolate candies, hallmark cards and romance, no other celestial region is more appropriate.
Located approximately 7,500 light-years from Earth in the constellation of Cassiopeia, the Heart Nebula (formally dubbed IC 1805, or Sh2-190) is an emission nebula that, quite obviously, has a silhouette resembling a beating heart. Only, instead of having blood flowing throughout it, thanks to the stars burrowed in the center of the region, our cosmic heart is pervaded by excited electrons, which have been ionized from the envelope of surround hydrogen gas. The outline itself is made up of large interstellar dust clouds, which are mostly opaque in visible light.
The bright spot on the right is NGC 896, which was the first independently discovered object in the nebula at the time, but now, we know an open cluster of stars exist near the nebula's center. Together, the brightest stars are 50 times the mass of our sun, with a small fraction of the stars being dim, an even smaller fraction of the stars are approximately as massive as the sun.
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