Leo I dwarf galaxy: a hidden treasure
Our home galaxy, the Milky Way, is not alone: a parade of small galaxies is all around it. Leo I, a dwarf galaxy, is one of them. Spotting it is not straightforward, as you are dazzled by Regulus, one of the brightest stars in the sky.
Surely, I will not surprise you telling that our Milky Way has a number of physical satellite galaxies. Two of them are visible to the unaided eye: the Large and the Small Magellanic Clouds (gems reserved to those living in the Southern Hemisphere). But there are many more: several tens, including confirmed members and candidates.
Among the confirmed members, the dwarf spheroidal galaxy Leo I is a remarkable one. It is among the most distant satellites of our cosmic island, placed at about 850.000 light years from us. As seen from our planet, Leo I lies almost exactly in the line of sight of the star Regulus, the 22nd brightest one in our our sky, in the constellation of Leo (hence the name), the Lion. But the star is “only” 80 light years away from us: 80 vs 850.000.
This apparent proximity makes the vision of Leo I quite hard, as you are dazzled by Regulus, which is about 10 arcmins apart (1/3 of the angular size of the lunar disk). It was discovered on 1950 and the evident light interference from Regulus made studying the galaxy not easy.
The image above comes from the average of four, 300-seconds exposures, unfiltered, remotely collected with the “Elena” (PlaneWave 17″+Paramount ME+SBIG STL-6303E) robotic unit available at the Virtual Telescope Project. Of course, the bright blob of light on the left is Regulus.
In our image, you can easily see how Leo I is resolved into many stars. We know that now star formation has basically almost ended there.
Support The Virtual Telescope Project!
Support us! Please, donate and receive unique, LIMITED EDITION set of images of the epic 27 July 2018 lunar total eclipse above Rome, of potentially hazardous asteroids and much more, specifically made for supporters like you!
(you can adjust the amount later)