Scientists have reported finding a new dwarf galaxy in the Magellan Bridge - a gas stream connecting two Magellan Clouds. The galaxy was named South Hydra 1, as it lives in the same small constellation in the southern sky. That is why the find was also called the “snake in the clouds”.
The Dark Matter Camera (DECam) on the Blanco 4-meter telescope at Cerro Tololo Observatory (Chile) was used for the search. Analysis of the spectroscopic data revealed a new ultra-weak dwarf galaxy.
The South Hydra 1 is a slightly elliptical ultra-weak system, distant from the Sun by 90,000 light years, and also 78,000 light years from the Large Magellanic Cloud. The absolute value reaches -4.7. The parameters indicate that we are likely to have a dwarf type or an extended globular cluster.
Density of the main sequence in the region of the Magellan Clouds. The location of the found dwarf galaxy is indicated between the Large Magellanic Cloud (left) and the Small Magellanic Cloud (right). Marked with a red dotted circle The review shows that the galaxy is endowed with an old, metal-poor, stellar population with several blue stars with a horizontal branch and two variables RR Lyra. The system is dominated by dark matter, which means it can be a globular cluster or a dwarf galaxy that has squandered matter due to tides.
The level of metallicity is approaching -2.5. The system has one carbon star with an extremely low level of metal (-3.0), and the ratio of carbon and iron is 3.0. The findings state that South Hydra 1 is part of the Magellan family of satellites. But additional observations will be needed to confirm.