The first exoplanet was discovered in 1992 and it opened up a new era of planetary science. Eight years later, a group of astronomers at the European Southern Observatory (ESO) took a series of infrared images of a brown dwarf. What they didn’t know at the time was they had also taken the first ever direct photo of a planet outside the Solar System.
In 1998, lead scientist Gaël Chauvin and his team of European and American astronomers at the ESO began an investigation of the TW Hydrae association, a collection of low-mass stars and substellar objects.
By April 2004, the group’s new target of the survey was a brown dwarf designated 2MASSWJ1207334-393254 (shortened to 2M1207) located 230 light years away from Earth. Using the Very Large Telescope at the Paranal Observatory in Chile, they obtained a number of infrared images and were surprised to see the brown dwarf was joined by a tiny red blemish.
The object was 100 times fainter than 2M1207 and the team couldn’t explain what it was. They suspected it could be an exoplanet and more observations were made two months later.
By September, the ESO group confirmed the object (now labelled 2M1207b) was an exoplanet, an extremely hot gas giant with about five times the mass of Jupiter. It orbited the brown dwarf at a distance close to that of the Sun and Neptune. The team announced their findings to the world.
The astronomers spent another year analysing 2M1207b. They utilised resources from the Hubble Space Telescope and Paranal Observatory. Evolutionary software models and a spectral data analysis of the 2M1207 system were run. All data pointed to the object being an exoplanet.
In 2016, 2M1207b was the subject of another in-depth study. The Hubble Space Telescope was used to measure the exoplanet’s spin, the first time such a feat had been achieved using direct imaging.
Led by the University of Arizona’s Daniel Apai, the team found interesting details in 2M1207b’s atmosphere during the investigation. A day on the exoplanet was measured to be about 10 hours long and it had complex cloud structures. Though based on the brightness observed, 2M1207b’s clouds were most likely bland in colour.
Due to its 1,400 plus degree temperature, the astronomers also predicted the exoplanet rains fine silicate particles at high elevations and iron vapour at lower levels in its atmosphere.
The science team believed 2M1207b and its companion brown dwarf didn’t form in the traditional sense where stars, planets and other objects are all created from the material in one accretion disk. Instead, they concluded the two could have formed from their own separate disks.
At only 10 million years old, 2M1207b is still very young and will cool down over the next few billion years.
As of 2022, over 5,000 exoplanets have been discovered. With the James Webb Space Telescope coming online, it will be possible to take many more direct images of them in even higher detail than ever before. This will greatly add to astronomers’ understanding of them and will create new breakthroughs in planetary science.
Photo Credit: European Southern Observatory (https://www.eso.org/public/images/26a_big-vlt/)
2M1207b – First Image of an Exoplanet (ESO) (https://www.eso.org/public/images/26a_big-vlt/)
2M1207b – First Image of an Exoplanet (NASA) (https://exoplanets.nasa.gov/resources/300/2m1207b-first-image-of-an-exoplanet/)
About: 2M1207b (https://dbpedia.org/page/2M1207b)
A Planet With Planets? Spitzer Finds Cosmic Oddball (https://www.nasa.gov/vision/universe/starsgalaxies/spitzerf-20051129.html)
Astronomers Measure Rotation of Cloudy Super-Jupiter (http://www.sci-news.com/astronomy/rotation-cloudy-super-jupiter-2m1207b-03646.html)
Fresh Debate Over First Photo of Extrasolar Planet (https://www.space.com/1023-fresh-debate-photo-extrasolar-planet.html)
Is This Speck of Light an Exoplanet? (https://www.eso.org/public/news/eso0428/)
Let the Great World Spin (https://exoplanets.nasa.gov/news/250/let-the-great-world-spin/)
Other Worlds (https://webb.nasa.gov/content/science/origins.html)
Yes, it is the Image of an Exoplanet (https://www.eso.org/public/news/eso0515/)