In the show this time, Dr David Kipping talks to us about exomoons, Dr Rob Beswick tells us about the e-MERLIN array in this month's JodBite, and your astronomical questions are answered by Dr Joe Zuntz in Ask an Astronomer.
JodBite with Dr Rob Beswick
Dr Rob Beswick works on the e-MERLIN radio telescope network, operated from Jodrell Bank Observatory. In this interview, he talks about the way the network operates, what it looks at and how it can help us to understand the births and deaths of stars using high-resolution radio imaging. He also tells us about a citizen science project to detect gravitational lenses, recently featured on the BBC's Stargazing Live television programme.
Interview with Dr David Kipping
Dr David Kipping looks for exomoons - moons around planets outside our Solar System - and is based at the Harvard Smithsonian Center for Astrophysics in Massachusetts. He explains the intensive computation involved in mining the data from the Kepler spacecraft in search of the tiny extra dip in a star's brightness that would indicate the presence of a moon around an exoplanet, and he looks forward to the prospect of the first such discovery. He discusses future missions, such as NASA's TESS and ESA's PLATO, which will seek extrasolar systems across more of the sky, and talks about the chemical analysis of planets and moons that will be possible with the coming JWST infrared telescope. Such analysis could reveal the signature of life on a planet, or, given the extra energy from tidal heating, on a moon.
Ask an Astronomer
Dr Joe Zuntz answers your astronomical questions:
- The first question is from Nigel Edwards: "How does a photon experience the passage of time as it travels through the Universe? If a photon travels for 100,000 years from our perspective, does the photon itself see the journey as instantaneous?"
- The next question, from Margaret Feaster, is: "Does the Earth's wobble affect the Moon's orbit?"
- Finally, Peter Conway says: "How do gravitational slingshots work to accelerate space probes as they pass planets? Why isn't the speed they gain as they approach a planet lost when they pull away from it?"
Odds and Ends
Another Rosetta update: ESA's comet-chasing probe has reached close proximity to its target, with the Rosetta spacecraft only 100 kilometres away as of the 6th of August. All the planned orbital manoeuvres to slow the probe to a relative velocity of 1 metre per second with respect to the comet have worked, and in the next few months the previously unseen comet will be mapped out in great detail as the mission planners search for an appropriate site for Rosetta's lander, Philae. If everything goes well, the latter should clamp onto the surface of the comet in mid-November, firing harpoons into comet 67P/Churyumov-Gerasimenko to secure itself to the surface.
Among the multiple conflicts in the world at this moment, the conflict in Ukraine has the potential to affect activities in space. Because of their differing political stances regarding Ukraine, the USA and Russia have imposed economic sanctions against each other. If the sanctions were extended to space-related activities, they could cause disruptions in a couple of different ways. First, NASA relies upon Russian rockets to get astronauts to the International Space Station (ISS). If Russia were to remove itself from the ISS collaboration, NASA would be unable to get astronauts to the station. Second, the USA imports Russian engines for their Atlas V rockets. If the USA could no longer buy these engines from Russia, it could potentially design and build replacements, but it would cause major disruptions to the USA's launch schedule.
Geologists and biologists have uncovered the secret life of microbes in the extreme cold and dark of a lake beneath the Antarctic ice sheet. Russian scientists first discovered organisms in Lake Vostok in 2013, and now an American team has drilled through to more in Lake Whillans. These tiny life-forms survive 800 metres beneath a glacier by using the chemical energy found in molecules such as ammonium, which are ground from rocks as the glacier moves. They provide further evidence of the possibilities of survival in harsh conditions, and will be a source of encouragement to efforts to search for alien life under the frozen surface of Jupiter's moon Europa.
|JodBite:||Dr Rob Beswick and Libby Jones|
|Interview:||Dr David Kipping and Indy Leclercq|
|Ask An Astronomer:||Dr Joe Zuntz and Indy Leclercq|
|Presenters:||George Bendo, Indy Leclercq and Mark Purver|
|Editors:||Indy Leclercq and Mark Purver|
|Segment Voice:||Tess Jaffe|
|Website:||Indy Leclercq and Stuart Lowe|
|Cover art:||The first gravitational lens to be discovered by citizen science, identified as part of the Zooniverse SpaceWarps project during BBC Stargazing Live in January 2014. CREDIT: Jim Geach/VICS82|