In October this year, the constellation Cetus can be seen in the night sky, which is visible to the naked eye, far above the horizon. It is also most likely looking in the general direction of an alien world called YZ Ceti b that has suddenly come to the attention of astronomers.
YZ Ceti b is a rocky, Earth-sized exoplanet (a planet orbiting a star other than our sun) orbiting a small red dwarf star, YZ Ceti, 12 light years from Earth, a handshake distance in astronomical terms. Astronomers are excited because they have detected repeated radio signals from this exoplanet indicating the presence of a magnetic field – a prerequisite for a habitable planet – in its vicinity.
How was it discovered?
The discovery was made by Jackie Feldsen of Bucknell University, Pennsylvania, and Sebastian Pineda of the University of Colorado, Boulder, using the Carl G. Jansky Large Array radio telescope in New Mexico. They published their findings in a journal natural astronomy on April 3rd.
They had to run several rounds of observations before they could detect radio signals from the star YZ Ceti, which appeared to match the orbital period of planet YZ Ceti b. From this, they concluded that the signal is the result of interactions between the planet’s magnetic field and the star.
said dr. Pineda via email to Hindu.
Why is the magnetic field important?
Just as bursts of energy from the Sun sometimes disrupt Earth’s telecommunications and damage Earth-orbiting satellites, intense bursts of energy from interstellar stars and exoplanet YZ Ceti produce stunning auroral glow.
“We see this indirectly in the radio broadcasts we receive,” said Dr. Pineda.
These radio waves, strong enough to be picked up on Earth, confirmed the existence of an extrasolar magnetic field. Such a signal can only be produced if an exoplanet orbits very close to its host star and has its own magnetic field to influence the stellar winds and generate the signal.
What is included in YZ Ceti b?
This is confirmed by YZ Ceti b’s tiny orbit: astronomers have determined that the planet only takes two Earth days to circle its star. In comparison, Mercury, which has the orbit of the smallest planet in the solar system, takes less than three Earth months to go around the sun.
Since the mid-1990s, astronomers have discovered hundreds of planets orbiting stars similar to the Sun, indicating that the formation of planets in the galactic universe is more common than scientists thought. Data from space science missions such as the Kepler, Gaia, and James Webb telescopes show that there are more than 300 billion planets in the Milky Way alone.
With so many exoplanets in the same “neighborhood” of the Sun, nearly half of all stars visible in the sky could host rocky Earth-sized planets in habitable orbits around them. In order to have a sustainable atmosphere and water, a planet must be a certain distance from its star (in an orbit said to be in the star’s “Goldilocks Zone”), or it will burn up.
Earth, for example, would be more like hot and sultry Venus if it was a little closer to the sun – or cold and arid like Mars if it was farther away. In fact, astronomers believe that about 30% of all discovered planetary star systems could contain a temperate zone.
How common is this magnetic field?
With numbers that big, it makes sense that strong planetary magnetic fields would be common outside the solar system. However, although many of the larger exoplanets discovered to date have magnetic fields, planetary scientists have simply never been able to pinpoint those fields. smallestAnd rocky Exoplanets – until now.
Dr Pineda noted that if the latest findings are confirmed by further research, they “will prove the potential of the methodology to lead to the magnetic characterization of exoplanets.”
This is important because the survival of a planet’s atmosphere may depend on the presence or absence of a strong magnetic field, as the field protects the atmosphere from erosion by charged particles blowing off the star. Dr Benady agrees: “Planets close to their stars are usually very hot and their atmospheres have likely been eroded over the billions of years of exoplanetary system history.”
What happened after that?
Surprisingly, Mars orbiting the Sun at a “safe” distance has a similar story to tell: Mars and Earth were almost the same billions of years ago, with lots of water, warm oceans, rainfall, and a similar atmospheric system. But even so, life began on one planet while another became dry and cold as the solar wind stripped most of its atmosphere. So this is also the story of YZ Ceti b?
“We hope to receive additional feedback on this target,” said Dr. Benadi. “Long-term observations are important to confirm these results and further investigate the properties of radio signals.” However, one thing is certain: The find will help astronomers learn more about the rocky underworlds in the depths of space that surround their host stars.
Prakash Chandra is a science writer.
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Astronomers are excited because they have detected repeated radio signals from YZ Ceti b – a rocky, Earth-sized exoplanet that indicates the presence of a magnetic field – a prerequisite for a habitable planet – in its vicinity.
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The discovery was made by Jackie Feldsen of Bucknell University, Pennsylvania, and Sebastian Pineda of the University of Colorado, Boulder, using the Carl G. Jansky Large Array radio telescope in New Mexico. They published their findings in a journal natural astronomy on April 3rd .
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This is important because the survival of a planet’s atmosphere may depend on the presence or absence of a strong magnetic field, as the field protects the atmosphere from erosion by charged particles blowing off the star.
