A beautiful image showing two interacting galaxies has been captured by a camera originally designed to study dark energy. The two galaxies in this image, NGC 1512 and NGC 1510, are part of an interacting pair that have been in the process of merging together for 400 million years. As the two come closer, drawn together by gravity, the forces are accelerating star formation and many new stars are being born.
Galaxy NGC 1512, which is the bigger galaxy on the left of the image, is a barred spiral galaxy like our Milky Way. Its smaller partner, galaxy NGC 1510, is a dwarf lenticular galaxy, meaning it is a small type of galaxy that has some properties of a spiral galaxy and some of an elliptical galaxy.
You can see the tendrils of dust and gas reaching out from the larger galaxy as the two merge, with the gravitational forces stretching out their shapes and powering the star formation seen in the stream of light between them. Eventually, the two will complete their merger and become one galaxy.
The pair is located in the constellation of Horologium, or the Pendulum Clock, which is visible in the southern hemisphere. at 60 million light-years away they were imaged in detail by using NOIRLab’s Dark Energy Camera, also known as DECam. This instrument, located on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory, was designed for investigating dark matter in a project called the Dark Energy Survey.
This project looked at wide fields of space to understand more about dark energy, and observations were concluded in 2019. Since then, DECam has been put to good use for collecting other data like this image of galactic interaction.
DECam “collect[s] starlight reflected by the telescope’s 4-meter-wide (13-foot-wide) mirror, a massive, aluminum-coated and precisely shaped piece of glass roughly the weight of a semi-truck,” NOIRLab explains.
“After passing through the optical innards of DECam — including a corrective lens nearly a meter (3.3 feet) across — starlight is captured by a grid of 62 charge-coupled devices (CCDs). These CCDs are similar to the sensors found in ordinary digital cameras but are far more sensitive, and allow the instrument to create detailed images of faint astronomical objects such as NGC 1512 and NGC 1510.”