The 'Forbidden' planet has been found in the 'Neptunian Desert'

The 'Forbidden' planet has been found in the 'Neptunian Desert'
Exoplanet NGTS-4b -- also known as 'The Forbidden Planet' Credit: University of Warwick/Mark Garlick

An exoplanet smaller than Neptune with its own atmosphere has been discovered in the Neptunian Desert, by an international collaboration of astronomers, with the University of Warwick taking a leading role.

New research, led by Dr. Richard West including Professor Peter Wheatley, Dr. Daniel Bayliss and Dr. James McCormac from the Astronomy and Astrophysics Group at the University of Warwick, has identified a rogue planet.

NGTS is situated at the European Southern Observatory's Paranal Observatory in the heart of the Atacama Desert, Chile. It is a collaboration between UK Universities Warwick, Leicester, Cambridge, and Queen's University Belfast, together with Observatoire de Genève, DLR Berlin and Universidad de Chile.

NGTS-4b, also nick-named 'The Forbidden Planet' by researchers, is a planet smaller than Neptune but three times the size of Earth.

It has a mass of 20 Earth masses, and a radius 20% smaller than Neptune, and is 1000 degrees Celsius. It orbits around the star in only 1.3 days—the equivalent of Earth's orbit around the sun of one year.

It is the first exoplanet of its kind to have been found in the Neptunian Desert.

The Neptunian Desert is the region close to where no Neptune-sized planets are found. This area receives strong irradiation from the star, meaning the planets do not retain their gaseous atmosphere as they evaporate leaving just a rocky core. However NGTS-4b still has its atmosphere of gas.

When looking for new planets astronomers look for a dip in the light of a star—this the planet orbiting it and blocking the light. Usually only dips of 1% and more are picked up by ground-based searches, but the NGTS telescopes can pick up a dip of just 0.2%

Researchers believe the planet may have moved into the Neptunian Desert recently, in the last one million years, or it was very big and the atmosphere is still evaporating.

Dr. Richard West, from the Department of Physics at the University of Warwick comments:

"This planet must be tough—it is right in the zone where we expected Neptune-sized planets could not survive. It is truly remarkable that we found a transiting planet via a star dimming by less than 0.2% - this has never been done before by telescopes on the ground, and it was great to find after working on this project for a year.

"We are now scouring out data to see if we can see any more in the Neptune Desert—perhaps the is greener than was once thought."


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More information: Richard G West et al, NGTS-4b: A sub-Neptune transiting in the desert, Monthly Notices of the Royal Astronomical Society (2019). DOI: 10.1093/mnras/stz1084
Citation: The 'Forbidden' planet has been found in the 'Neptunian Desert' (2019, May 29) retrieved 24 June 2019 from https://phys.org/news/2019-05-forbidden-planet-neptunian.html
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May 29, 2019
It's interesting, but a planet at 1000 deg. C. is a slag heap, not much more.

May 29, 2019
Researchers believe the planet may have moved into the Neptunian Desert recently, in the last one million years, or it was very big and the atmosphere is still evaporating.

This assumption arises because without it they will have great difficulty explaining why a supposedly 5 - 10 billion year old planet sitting in that zone still has an atmosphere left AND why it is in fact of Neptunian size.
Fact of the matter is they have absolutely no clue how and when that planet got there and therefore their assumption is simply hot gas. Why would the planet decrease in size? No answer given - it is irrational, at least the way it's stated.

May 29, 2019
Just so by the way - the article does not clarify what NGTS stands for:
Next-Generation Transit Survey. I wish people would take more care in their editorials.

May 29, 2019
supposedly 5 - 10 billion year old planet


where the hell are you getting these numbers from?

May 29, 2019
In other words... it is all speculation. Every time I hear scientists be sure of something I feel like laughing. They are so arrogant and yet this — The fact they have no solid clue about 95% of what they say —keeps happening over and over and over. Scientists of the 21st are so underwhelming.

May 29, 2019
"It orbits around the star in only 1.3 days" how is that orbit and speed sustainable?

May 29, 2019
supposedly 5 - 10 billion year old planet


where the hell are you getting these numbers from?


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