South African Scientists Collaborate with NASA on Pluto Research

In 2006, the International Astronomical Union made waves by downgrading Pluto from its planetary status. While many were shocked, Pluto has continued to captivate scientists and researchers. Now classified as a dwarf planet, it resides in the Kuiper Belt, an icy region of the solar system.

Despite its demotion, Pluto still has many secrets to reveal, which is why scientists from South Africa have partnered with NASA to study the dwarf planet. Their mission: gain insights into Pluto’s atmosphere as it continues to move away from the Sun.

The Importance of Pluto

Pluto orbits the Sun on a 248-year-long elliptical path, reaching its closest point to the Sun in 1989. Since then, it has been moving farther away, and scientists believe its atmosphere might freeze onto its surface soon. This rare event has attracted global interest, leading to the latest collaboration between South African physicists and NASA.

To understand this process better, South African researchers from the University of the Western Cape (UWC) have joined NASA’s international mission. The team’s research focuses on astronomy and stellar explosions, giving them a unique angle on this critical mission.

The Occultation Event

The event that drew South African scientists into this mission is called an occultation. An occultation occurs when a celestial body passes in front of a distant star, temporarily blocking its light. During this brief moment, the atmosphere of the passing object can act as a lens, offering a rare opportunity to observe its characteristics.

For Pluto, observing such an event is essential. The dwarf planet’s atmosphere is expected to collapse in the coming years. Understanding the changes in its atmosphere could give researchers insight into similar processes occurring on other icy bodies in the outer solar system.

South Africa’s Role in the Mission

To observe this occultation, the UWC team used a Newtonian telescope provided by the University of Virginia. This high-tech 0.5-metre telescope was essential for capturing Pluto’s shadow as it passed over South Africa and Namibia at a staggering speed of 85,000 km/h.

On 4 August 2024, the team set up their viewing spot 40km north of Upington, Northern Cape. This precise location allowed them to catch Pluto’s shadow during the occultation. Despite facing challenges like cloudy skies and an unexpected gust of wind that shook the telescope, the team captured crucial data.

Though the occultation lasted mere seconds, the team hopes that the observations will reveal key information about Pluto’s atmosphere, including its temperature and chemical composition.

What’s Next?

Currently, the data is being processed to remove noise caused by the wind surge. The scientists are optimistic that the central flash observed during the occultation will provide essential information on how Pluto’s atmosphere refracts light. This data is crucial for understanding whether Pluto’s atmosphere is contracting as it moves away from the Sun.

Although it’s too early to share detailed findings, the UWC team is excited about the potential discoveries. If this year’s data doesn’t yield results, they will get another chance next year, when another occultation is expected to occur.

A Step Forward for South African Astronomy

This mission marks a significant achievement for South African science. The UWC team’s involvement in a major NASA-funded mission highlights the country’s growing role in international astronomy and space research. With their skills in nuclear physics, the team is poised to contribute valuable insights into Pluto and other celestial bodies.

For now, they eagerly await the results of their observations, hopeful that their work will unlock new knowledge about the mysterious dwarf planet at the edge of our solar system.