A Story Of Interacting Galaxies: The Antennae
Together, multiple wavelengths of light provide a snapshot of the complete stellar lifecycle.
Galaxies are the universe’s cities of stars, and like cities they change over time in population, structure, and appearance. When galaxies are drawn toward each other by gravity, stars and planets can pass by each other unharmed, but the gas and dust between stars collide. The gas is compressed and heated, setting off waves of new star formation. Some of these new stars are massive and have a short, bright life, allowing multiple phases of a massive star’s “lifecycle” to be viewed together, if the correct wavelengths of light are combined.
The Antennae galaxies provide a stunning multi-wavelength view of galaxy interaction and all the resulting phases of the stellar lifecycle. Interacting galaxies typically swing by each other multiple times, each time compressing gas to form new stars. Telescope observations in different wavelengths show how the interaction has unfolded over time, with X-ray binary stars and diffuse X-ray gas indicating earlier waves of star formation. Humans have studied stars for thousands of years, but much of their formation process is still mysterious; interacting galaxies like the Antennae provide insight not only into how galaxies change over time, but also the cyclical pattern of stars, which seems to grow more wondrous the more it is understood.
Quick Facts: The Antennae
Also known as:
NGC 4038 (upper galaxy) and NGC 4039 (lower galaxy)
Type of object:
Spiral galaxies
Distance from Earth:
68 million light-years
Location in the sky:
Corvus Constellation
Did you know:
The interaction between these two galaxies is ongoing, and has already been occurring for more than 100 million years.
Credits: The Antennae
Radio image from the ALMA telescope: ESO, NAOJ, NRAO
Infrared light image from the Spitzer Space Telescope: NASA, JPL-Caltech
Visible light image from the Hubble Space Telescope: NASA, ESA
X-ray light image from the Chandra X-ray Observatory: NASA, CXC, SAO
Multi-wavelength image, X-ray: NASA, CXC, SAO; Infrared: NASA, JPL-Caltech; Visible: NASA, ESA
Subject-matter expertise provided by Dr. Brad Whitmore
Produced by the Space Telescope Science Institute’s Office of Public Outreach