In the show this time, we talk to Hugo Messias about Gravitational lensing, Bob Watson tells us about Three decades of Cosmic Microwave Background(CMB) in this month's JodBite, and your astronomy questions are answered by George Bendo in Ask an Astronomer.
JodBite with Bob Watson
A longtime fan of the Jodcast, Dr Bob Watson is a research fellow at the University of Manchester. During his career, Bob has straddled the line between instrumentation and observation, all the while studying the light from the early Universe. He talks to the Jodcast about what cosmic microwave background observations can tell us about the early Universe, our galaxy and (possible) even inflation.
Interview with Hugo Messias
Tom Scragg interviews Dr. Hugo Messias as part of the Measuring Star Formation in the Radio, Millimetre, and Submillimetre meeting held at the Jodrell Bank Centre for Astrophysics on 24-26 July. Hugo discusses gravitational lensing, galaxy mergers and what it's like working in the Atacama desert as part of a multi-national team."
Ask an Astronomer
George Bendo answers your astronomical questions:
- James Walters asks:"Have any black holes been found that are not at the centre of a galaxy?"
- David Kings asks: "Would there be any noticable orbitable changes in the Local Group of galaxies, following the merger of the Andromeda and the Milky Way galaxies? i.e I'm assuming the combined mass would possibly have greater gravitational effect on other objects."
- Hein Du Plessis asks: "How do we know that C (the speed of light) is constant over time and size of the universe? Would a C relative to the size of the universe not explain accelerating expansion more elegantly?"
Odds and Ends
We discuss the legacy of John Wall (1932 - 2018), who sadly died last month. John was the inventor of the Crayford focuser, commonly found as part of many amateur optical telescopes. John named the focuser after his local astronomical society and decided not to patent his invention, effectively donating it to the amateur astronomical community. He also made the largest refracting telescope ever built by a single person. His many inventions, contributions, and achievements will be used and remembered for many years to come.
In a recent individual achievement from the world of cosmology, Prof. Peter Coles (of Cardiff and Maynooth (IRE) universities) has out-bearded a host of competitors to scoop the prestigious Beard of Winter 2017/18 award, as presented by the Beard Liberation Front (BLF). The prize "focuses both on fuller organic beards, suitable for winter weather but also on beards that have made an early New Year impact in the public eye ". You can follow Prof. Coles and his beard over at his blog, In The Dark.
We also bid farewell to Claire Bretherton, who is moving on to pastures new after 8 years at Carter Observatory (and working on Night Sky South for nearly as long!). We hope you'll join us in wishing her all the best on her future adventures.
Down here in the troposphere we're generally not too worried about space weather. Similarly, if you were a satellite in geostationary orbit, a hurricane down here on Earth probably wouldn't concern you too much. However, if you're a resident of the thermosphere, a region 50-400 miles above the surface, then you'd be checking both the space and terrestrial weather forecasts regularly. This region of the atmosphere is home to the International Space Station and many low-Earth orbit satellites. Consequently, it's important to know the effects of earth and space weather on our satellites and our astronauts. NASA launched the Global-Scale Observations of the Limb and Disc (GOLD) mission on January 25th with a view to studying how sensitive the conditions in the thermosphere are to the weather above and below. The mission is on its way to geostationary orbit where it will scan the entire disc of planet Earth every 30 minutes to measure the temperature, pressure and abundance of oxygen and nitrogen in the thermosphere. This is the first time that measurements have been taken of this region with such high cadence. Increases in pressure can cause greater drag on satellites causing corrective maneuvers to be required to correct orbits. An increase in the ion content due to solar wind activity can cause charges to build up on spacecraft or in sensitive electronics which, when discharging, cause false radio signals to be seen, or worse, failure of the components entirely. Also, radio signals that propagate that region, to and from satellites, can be affected by solar activity too and so as an increasing amount of our infrastructure is based in orbit, these measurements are invaluable. More info can be found here.
|JodBite:||Bob Watson and Monique Henson|
|Interview:||Hugo Messias and Tom Scragg|
|Ask An Astronomer:||George Bendo and Eunseong Lee|
|Presenters:||Emma Alexander, Jake Morgan, Ben Shaw|
|Editors:||George Bendo, Andreea Dogaru, Tom Scragg|
|Segment Voice:||Mike Peel|
|Website:||Naomi Asabre Frimpong and Stuart Lowe|
|Producer:||Naomi Asabre Frimpong|
|Cover art:||This image from the NASA/ESA Hubble Space Telescope shows a galaxy cluster, SDSS J1038+4849, that appears to have two eyes and a nose as part of a happy face. CREDIT: NASA/ESA|