‘Extra-solar’ planets are those outside our Solar System and more than 200 have been discovered orbiting stars close to our own Sun. The planet with water in its atmosphere is known as HD 189733b, and orbits a star in the constellation of Vulpecula the Fox, which is 64 light years from the Sun. HD 189733b is known as a “transiting planet” because it passes directly in front of its star, as viewed from the Earth.
The researchers, led by Dr Giovanna Tinetti of the European Space Agency and UCL’s Department of Physics & Astronomy, found that as HD 189733b passes in front of its ‘sun’, it absorbs starlight in a way that can only be explained by the presence of water vapour in its atmosphere. This is the first time that astronomers have been able to confirm that water is present on an extra-solar planet.
Dr Tinetti, who has recently taken up a prestigious Aurora Fellowship at UCL, said: “Although HD 189733b is far from being habitable, and actually provides a rather hostile environment, our discovery shows that water might be more common out there than previously thought, and our method can be used in the future to study more ‘life-friendly’ environments.”
The discovery was made using NASA’s Spitzer Earth-orbiting telescope, taking measurements at a number of key wavelengths in the infrared region of the spectrum that pick out the crucial signature of water. The water detection relied not only on Dr Tinetti’s painstaking analysis, but also on the calculation of highly accurate water absorption parameters by Dr Bob Barber and Professor Jonathan Tennyson, both of UCL’s Department of Physics & Astronomy.
Dr Barber said: “The absorption parameters were calculated from our Barber-Tennyson list of water vapour spectral lines. This includes over 500 million individual absorption features, each like fingerprints, giving us vital clues to the amount of water present and the temperature of the atmosphere.”
Professor Tennyson, who heads UCL’s Physics & Astronomy Department, explained: “Parts of the atmosphere of HD 189733b are very hot – around 2,000 degrees. You need the millions of lines we calculated to simulate this, putting in absorption accurately where it should be and – just as accurately – giving gaps for the light to get through the atmosphere, where it can.”
HD 189733 is a star very much like our own Sun, although a little cooler. Its planet is not like Earth, however. HD 189733b is a gas giant planet, about 15 per cent bigger than Jupiter. However, while Jupiter is over five times as far away from the Sun as our Earth is, HD 189733b is more than 30 times closer to its star than the Earth is to the Sun – explaining why it’s so hot.
Dr Tinetti added: “The ‘holy grail’ for today’s planet hunters is to find an Earth-like planet that also has water in its atmosphere. When it happens, that discovery will provide real evidence that planets outside our Solar System might harbour life. Finding the existence of water on an extra-solar gas giant is a vital milestone along that road of discovery.”
David Weston | alfa
APEX takes a glimpse into the heart of darkness
25.05.2018 | Max-Planck-Institut für Radioastronomie
First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
25.05.2018 | Event News
02.05.2018 | Event News
13.04.2018 | Event News
25.05.2018 | Event News
25.05.2018 | Machine Engineering
25.05.2018 | Life Sciences