Exploring Exoplanets with JWST. In November's episode, Mel talks to Dr Hannah Wakeford on her work in the field of exoplanets, utilising JWST to delve into planetary atmospheres. For our Jodbite, we talk to postdoc Dr Aishrila Mazumder about her research mapping hydrogen.

The News

Lift off for mission to investigate habitability of solar system moon

On 14th October NASA’s Europa Clipper spacecraft was launched from the Kennedy Space Centre in Florida. Europa Clipper is currently on its way to study Europa, one of Jupiter’s 95 moons. It is one of Juppiter’s largest moons, first observed by Galileo in 1610, and shows strong signs of having a liquid water ocean beneath its smooth ice crust. The spacecraft will perform repeated close fly-by’s of the moon to meet its three main science objectives, which are to understand the nature of the icy crust, the ocean and the moon’s geology. This information will help to improve our understanding of the astrobiological potential for life beyond Earth as the moon has all the ingredients needed for life as we know it, namely water, organic chemistry, energy sources causing eruptions on the ocean floor and conditions which have been stable for around four billion years. Our knowledge of Europa has been formed by previous missions exploring Jupiter, such as Juno and Galileo, but this is the first mission focussed on the moon itself.
The instruments on board the spacecraft include cameras to produce high resolution images, spectrometers to help produce composition maps, a radar which will be able to search through the ice for subsurface water and a magnetometer which will help to understand more about the moon’s interior.
Europa Clipper will reach its destination in April in 2030, having travelled 1.8 billion miles. Once it arrives it will make nearly 50 flybys of Europa whilst orbiting Jupiter, going to altitudes as low as 16 miles above the surface. It will cover a different section each flyby resulting in almost full coverage of the moon by the end of its mission.

New Exoplanet found very close to us!

On October 1st, 2024, a team of astronomers using the European Southern Observatory’s Very Large Telescope confirmed the existence of an exoplanet orbiting Barnard’s star, the closest single star to our Sun.
Barnard’s star, located just six light-years away, is a red dwarf and the second-closest stellar system to Earth, after the Alpha Centauri system. Given its proximity, Barnard’s star has long been a prime target for the detection of exoplanets, especially low-mass, rocky planets. However, despite previous detection signals, no exoplanet had been confirmed. But today, we officially welcome Barnard b , a small, rocky planet with at least half the mass of Venus.
Barnard b is an intriguing find. It’s twenty times closer to its star than Mercury is to our Sun, completing an orbit in just 3.15 Earth days. However, its surface temperature of 125°C, while being rather low, is far too hot to sustain liquid water. Barnard b is alas still located too close from it’s star to host life as we know it, placing it well outside the habitable zone. The research team, led by Jonay González Hernández of the Instituto de Astrofísica de Canarias, spent over five years gathering precise radial velocity measurements with the VLT’s ESPRESSO spectrograph. This high-precision instrument detected the changes in Barnard’s star’s light caused by the gravitational influence of an orbiting planet, providing a clear signal of Barnard b’s existence.
And here’s where it gets even more interesting: astronomers have also found hints of three more potential exoplanets orbiting Barnard’s star. Though further observations are needed to confirm them, it shows our cosmic backyard is full of low-mass planets. González Hernández remarked, “Even if it took a long time, we were always confident that we could find something.” And they did—Barnard b now stands as one of the smallest and closest exoplanets known.
Looking ahead, this discovery paves the way for even more detailed studies using next-generation telescopes. The Extremely Large Telescope currently under construction in Chile, is expected to play a key role. It’s ANDES spectrograph will allow for in-depth atmospheric studies of small, rocky planets, particularly those in the habitable zones of nearby stars.
As our detection methods become more refined, the study of Barnard’s star and its planetary system opens up new avenues in the search for low-mass exoplanets, expanding our understanding of planetary systems within our galactic neighbourhood.

Interview with Dr Hannah Wakeford

For this month's interview, Dr Hannah Wakeford visits JBCA to explain how she models exoplanet atmospheres in her work at the University of Bristol. In this Jodcast interview, find out how she got to where she is now and uncover what to expect when her research revisits the Trappist-1 system.

Jodbite with Aishrila

In this Jodbite, Jessy speaks with JBCA Postdoc Dr Aishrila Mazumder about her work on mapping Hydrogen using the 21 cm signal using the Meerkat Radio Telescope in South Africa and how this can be used to study how the distribution of matter evolves over time.

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News : Phoebe Ryder and Nastassia Raffy
Interview : Dr Hannah Wakeford and Melissa Azombo
Jodbite : Aishrila Mazumder, Jessy Marin and Barbara Cabrales
Editors : Jordan Norris, Jamie Incley, Tobias Russell
Website : Lily Correa Magnus
Producer : Lily Correa Magnus
Cover Art : The Moon, pictured on May, 21, 2022, the day before going into its Last Quarter phase, is seen from the space station as it orbited 266 miles above the Pacific Ocean. CREDIT:NASA Blogs: Space Station (2022, May) Science Full Speed Ahead as Station Preps for Cargo Mission.