Will Gater - "Alien Worlds" Lecture

On Wednesday we were treated to an enthralling lecture by returning speaker, Will Gater. 

Will, an Astrophysics graduate of UCL, is a freelance journalist of astronomy, author of several books and a regular presenter on TV and radio. 
 
Entitled "Alien Worlds: the extraordinary inhabitants of the Milky Way" Will took us on a spectacular tour of the burgeoning field of Exoplanets.  Setting the scene with Ancient Greek and Middle Ages philosophical reflections on the Plurality of Worlds, he took us through the groundbreaking discoveries of exoplanets,  namely those around Pulsar PSR B1257+12 in 1992, detected by investigating radio pulse anomalies, and then those orbiting a main sequence star, 51 Pegasi, identified in 1995 by the radial velocity method.  
 
Will continued to explain in detail the various methods of detection employed,  including the transit method, gravitational micro-lensing and the aforementioned radial velocity "Doppler shift" technique.  The Kepler mission, of course, featured largely and how its astonishing catalogue of discoveries continues despite its severely curtailed capabilities owing to mechanical problems.  
 
Will related the initial shock and still not fully understood nature of exoplanetary systems and their dissimilarity to our own.  The plethora of close orbiting  "hot Jupiters" and "super Earths" and corresponding paucity of systems structured like our Solar System is a distinct puzzle for near-future projects such as the EELT, JWT, TESS and others to try and solve. 
 
Having outlined the caveats in getting too excited about Earth-sized worlds in "Goldilocks Zones" around other stars, Will finished his brilliant (and non-stop!) talk on a fine up-note by presenting  the staggering extrapolated statistics of Earth-sized,  temperate worlds in the Milky Way.  There are probably billions out there,  he concluded, as we applauded another truly excellent evening and speaker at WAS lecture-night.

Mark Cullen

Jakub Bochinski lecture of Evaporating Exoplanets

Evaporating Exoplanets" was the third lecture given to us by Jakub Bochinski from the Open University on Wednesday 17th September 2014. Jakub had just returned from a series of conferences throughout Europe, and gave us an in-depth update on the subject.

The first exoplanet was discovered in 1992, last year there were 967, and to date the number is approximately 2,000.  However the rate of discoveries is now believed to be 1,000/year and up to 3/day.  Some exoplanets transits in front of their star and are hot or cold depending on how close or how far away from their stars they are.

Jakub told us about two exoplanets that he had been studying recently.   WASP-12b is among the hottest known gas giants, it is highly irradiated, has a temperature of 2500 Kelvin, and is surrounded by an extended cloud of gas, which the planet is flying through.  The timings of planets' transist have been observed through photometry in different wavelengths by the ULTRACAM camera on the back of the William Herschel Telescope, and translated into light curves.   Because of the noise in the WASP-12b data, Jakub has written a piece of software he has called ULTRACorrect, which corrects noise at 100,000 pixels/second and leaves a clear data set to perform analysis on.   This analysis is still ongoing and we are hoping to hear about it more in the future.

The other exoplanet, KIC 12557548b is a Merury sized exoplanet with a temperature of 2,100 Kelvin, which is shown to be geologically active, actively disintegrating in front of our telescopes, and creating a comet-like dust tail, which follows the planet.   It is hoped that Jakub will be able to find out the size of dust grains in the tail, and potentially  even look under the planet's surface to start asking questions about its composition.

What next!  The NASA Kepler probe is the most successful exoplanetary mission so far.   Future missions are - the ESA CHEOPS due for launch in 2017, the NASA TESS probe, and the ESA M3 class PLATO 2 planned for 2024. The last one should produce a wealth of targets for follow-up studies by any ground-based observatory.  There are two designs planned for this, a single telescope with a wide field of view, and a telescope with multiple lenses, similar to the SuperWASP observatories.   All these missions will study exoplanets and their stars in different ways.

Jakub has written a paper about his most recent and exciting observations, and concluded his lecture with the words "The Future is here."   The lecture produced a lot of questions from members.

We had hoped to have another lecture on exoplanets in the future.   Although Jakub might be moving abroad shortly, he has offered to help our Society set up our observatory telescope so that we can observe exoplanets ourselves.   We look forward to taking him up on his offer.

Our thanks go to Jakub for yet another interesting and informative lecture.

Jan

  

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Jakub 

Jakub Bochinski-Exoplanets

In November, Jakub Bochinski gave a wonderful and very popular lecture titled “From pole to pole-a short tale of extrasolar planets & how we find them”.

Last year Jakub gave a very informative, interesting & well received lecture introducing exoplanets. He is currently working at the Open University researching exoplanets.

Jakub gave a brief description explaining what exoplanets are & that the first exoplant was found in 1992 by Alexander Wolzczan. He explained that there are currently 974 confirmed exoplants and thousands of candidates, showing graphs and diagrams to explain this. Jakub has co authorised some of the most recently discovered exoplanets and has starting looking into exogiant galaxies.

He went on to explain how habitable these planets maybe for life, the size of the planet and what it is made of. He explained the methods used to find exoplanets which are: Pulsar timing, Radical velocity, Eclipse timing, Micro gravitational lensing and Transit searching. Transit searching is the method which has led to the discovery of the most exoplanets.

He makes his observations using data obtained from the Superwasp telescopes and by following possible leads up with the automated pirate telescope. He finished by telling us about future missions using the ‘Tess’ satellite and the ‘James Webb telescope’.

After appreciative applause he went onto judge the photographic competition.