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Thorne-Zytkow Objects Facts for Kids
Discover 20 amazing facts about Thorne-Zytkow Objects, sourced from NASA and written for kids to understand and enjoy. Want to explore Thorne-Zytkow Objects in 3D? Launch the game to visit!
What Is a Thorne-Żytkow Object?
A Thorne-Żytkow Object (TZO) is a bizarre star-within-a-star — a red supergiant with a neutron star hiding at its core! It was predicted by physicists Kip Thorne and Anna Żytkow in 1977.
Meet the Discoverers!
Kip Thorne won the Nobel Prize in Physics in 2017 for gravitational waves. Anna Żytkow is a Polish-born astrophysicist. Together they imagined what would happen if a neutron star fell into a red supergiant!
How Do TZOs Form?
A TZO can form when a neutron star in a binary system spirals into its companion red supergiant. The neutron star sinks to the center and becomes the new "engine" powering the giant star!
The Deadly Spiral!
In a close binary system, the neutron star loses orbital energy through tidal friction with the giant's envelope. Over thousands of years, it spirals inward until it reaches the core — creating a TZO!
Born from a Supernova Kick!
Another way a TZO can form is when a supernova explosion gives the newly-born neutron star a "kick" that sends it crashing directly into its companion star!
Unusual Nuclear Burning!
In a normal star, nuclear fusion happens in the core. In a TZO, material falls onto the neutron star surface and undergoes exotic nuclear reactions, creating elements that normal stars can't make!
The irp-Process!
TZOs produce elements through the "interrupted rapid proton capture" (irp) process. This creates unusual amounts of rubidium, molybdenum, and lithium — a chemical fingerprint that helps astronomers identify TZOs!
Masters of Disguise!
From the outside, a TZO looks almost identical to a normal red supergiant! The only way to tell the difference is by carefully analyzing the star's light for those telltale unusual elements.
A Real Candidate: HV 2112!
In 2014, astronomers found HV 2112 in the Small Magellanic Cloud — a red supergiant with excess rubidium, lithium, and molybdenum. It might be the first TZO ever identified, though the debate continues!
Another Suspect: HV 11417!
HV 11417 is another red supergiant in the Small Magellanic Cloud that shows some TZO-like chemical signatures. Finding more candidates helps scientists understand how common these weird objects might be.
Giant Convection Currents!
Inside a TZO, enormous convection currents carry material from near the neutron star core all the way up to the star's surface — a journey of millions of kilometers! This is how the unusual elements reach the surface.
Absolutely Enormous!
A TZO would be about the same size as a red supergiant — roughly 1,000 times wider than our Sun! If placed at the center of our solar system, it would swallow Mars and possibly Jupiter!
Layers of Extreme Heat!
The surface of a TZO is relatively cool at about 3,500°C (like a normal red supergiant), but temperatures soar to billions of degrees near the neutron star core — hotter than the center of a supernova!
A Brief Cosmic Life!
TZOs probably only exist for about 100,000 to 1 million years before the neutron star either consumes enough material to collapse into a black hole, or the outer layers are blown away entirely!
Neutrino Factories!
The neutron star core of a TZO produces enormous numbers of neutrinos — ghostly particles that pass right through normal matter. These neutrinos actually help carry energy away from the core!
How Do TZOs Die?
A TZO can end its life in several dramatic ways: the neutron star might collapse into a black hole, the envelope might be ejected leaving a bare neutron star, or the whole thing might explode as an unusual supernova!
Gravitational Wave Whispers!
When the neutron star first spirals into the red supergiant, it might produce detectable gravitational waves — ripples in spacetime that advanced detectors like LIGO could potentially pick up!
Incredibly Rare!
Scientists estimate there might be only 20 to 200 TZOs in our entire Milky Way galaxy at any given time. That's incredibly rare compared to the hundreds of billions of stars in our galaxy!
Magnetic Mayhem!
The neutron star at the core of a TZO has an incredibly strong magnetic field. As material from the supergiant falls onto it, the magnetic field channels the gas into violent eruptions and jets!
Source: NASA · Last updated: