What Are the Penguin and the Egg Galaxies?

A vivid portrait captured by the James Webb Space Telescope commemorates its second science anniversary by showcasing a duo of interacting galaxies known as Arp 142. These galaxies, individually catalogued as NGC 2936 (the Penguin) and NGC 2937 (the Egg), have been engaged in a cosmic dance that started between 25 and 75 million years ago. Their interaction set in motion a series of gravitational interactions that will eventually lead to their merger into a single galaxy hundreds of millions of years from now.

How Does Webb Capture These Interactions?

Webb's specialization in capturing infrared light, which is beyond human visual perception, allows for a unique view of these interacting galaxies. The telescope's combined near- and mid-infrared observations from its NIRCam (Near-InfraRed Camera) and MIRI (Mid-Infrared Instrument) reveal the galaxies joined by a blue haze of mingled stars and gas. This detail underscores the complexity and beauty of their cosmic dance.

What Does the "Dance" of the Penguin Look Like?

Before their first approach, the Penguin galaxy held the shape of a spiral. Today, it has transformed, with its galactic center gleaming like an eye and its unwound arms forming a beak, head, backbone, and fanned-out tail. This transformation is a result of the gravitational pull exerted by the Egg galaxy, causing the Penguin’s thinner areas of gas and dust to crash in waves and form new stars.

Why Is the Egg Galaxy Less Affected?

In contrast to the Penguin, the Egg galaxy remains largely unchanged. As an elliptical galaxy, it is filled with aging stars and has less gas and dust available for new star formation. Additionally, the Egg's compact shape and comparable mass to the Penguin prevent it from being significantly consumed or distorted during their interaction.

What Other Cosmic Entities Are Present in the Image?

The top right of Webb's image features an edge-on galaxy, catalogued as PGC 1237172, residing 100 million light-years closer to Earth. This young galaxy teems with new, blue stars, which practically disappear in mid-infrared light captured by Webb. This contrast highlights Webb’s ability to distinguish between stellar populations of different ages and compositions.

How Does Webb Compare to Hubble in Observing Arp 142?

Webb's image of Arp 142 is overflowing with distant galaxies, some with spiral and oval shapes, while others appear as shapeless dots. This is a testament to Webb's sensitivity and resolution. Comparing Webb's view to a 2013 image from the Hubble Space Telescope reveals that Webb can detect far more distant, redder, and dustier galaxies, emphasizing its superior capabilities.

What’s Next for Webb in Its Scientific Journey?

Over its second year of operations, Webb has continued to advance scientific understanding of the universe. It has made new discoveries about other worlds, the lifecycle of stars, and the early universe. Webb's observations have helped solve mysteries about the universe’s reionization, detected the most distant black hole merger, and confirmed longstanding discrepancies in the Hubble constant measurements.

How Does International Collaboration Enhance Webb's Capabilities?

Webb represents a significant international partnership between NASA, ESA, and the Canadian Space Agency (CSA). ESA provided the telescope’s launch service using the Ariane 5 vehicle, along with crucial instruments like the NIRSpec and 50% of the MIRI. This collaboration has been essential in enabling Webb to deliver groundbreaking discoveries and enhance our understanding of the cosmos.

POLL TIME

Stay tuned for more discoveries as Webb continues to explore the universe and unveil its many mysteries!🚀