Astrophiz 69 ~ Dr Chris Lidman

Episode69c copy

This is the second of 6 ‘Astrotour’ episodes of Astrophiz, where we’ll be publishing recordings of interviews I did on a two and a half thousand kilometre tour of five of Australia’s finest Eastern state radio and optical observatories.

Dr Chris Lidman, who is the first Director of the ANU Siding Spring Observatory, which is deep in a pristine dark sky parkin the Wurrumbungle ranges in North Eastern New South Wales in Australia. Chris was a member of the team which shared the 2011 Nobel Prize for Physics andhas more than 30,000 citations from 197 research papers and more than 100 other publications. So apart from being a very active researcher, he has responsibility for many of the telescopes based on site, from the powerful Skymapper right up to this immense 3.9m AAT

We also extend our condolences to Dr Ian Musgrave, whose 96yo mother passed away recently. He will be back with us in two weeks.

So in Ian’s absence for this episode, I’ll try to give a shortened version of Ian’s expert commentary “What’s Up Doc” and I’ll try to give you an idea of some things to watch out for in the sky over the next couple of weeks.

My observational knowledge is basic at best, so I cranked up a free bit of software that Ian introduced me to called Stellarium.
I made the location Adelaide in South Australia and set the time for dusk on Sunday 4th of November and at 8:20pm, if you have a low horizon, you’ll see Jupiter setting, followed rapidly by Mercury. It’s not often you get to see Mercury, It is moving so fast and so close to the sun, so why not pop out to have a look after sunset.
Mercury sets about 9pm, followed by the giant red eye of the Scorpion, Antares. By 10:30 pm The Milky way has carries Saturn with it down to set on the western horizon, And if you follow the ecliptic upwards, Mars is still quite high in the west.

For astrophotographers who are  morning people who want to capture the very thin crescent moon at 4% illumination around 6am on Tuesday 6th November. This will be a great challenge because the sunrise is only about 20 minutes after moonrise. And remember, if you point your camera at the sun, you will not only blind yourself for life, you’ll also wreck your cameras CCD.

For normal people who dont get up early, to capture the very thin crescent moon at 3% illumination, you might catch it just after the sun sets around 8pm on Friday 9th November.

And if you’re really clever, you’ll get the sliver of the moon, Mercury Jupiter and red Antares all in the one shot. If anyone does that, send your image to me @Astrophiz on Twitter, and I’ll re broadcast it for you.

Also on the 11th November in the West at about 9:00 the crescent moon and saturn will be close together.

Now because I’m doing an Ian here, I’ll go off on one of his astronomical tangents about Mercury.
The BepiColombo Mercury mission was launched from French Giana. This is a joint venture between the European Space Agency (ESA) and the Japanese space agency, Jaxa.

 BepiColombo involves not one orbiter but two. Once the spacecraft has been delivered into orbit around Mercury by the ESA-built Mercury transfer module, it will split into two,  and release the Mercury magnetospheric orbiter, built by Jaxa, and the Mercury planetary orbiter, built by ESA.

It will travel 9Bn Km and takes 7 years to get there. You can’t just drop a spacecraft down the gravity well to the sun and go into orbit around Mercury. It’s more complex and much more elegant than the Famous Rich Purnall manoeuvre. The craft was given an initial boost two weeks ago onto of the European’s most powerful rocket, the Arianne, Then it does a series of slingshot flyby’s to match Mercury’s orbital velocity. First there one return-to-earth earth flyby in 2020, then 2 Venus fly-bys in 2020 and 2021, then six flyby’s of Mercury till it finally matches velocity and arrives in orbit in 2025, 

“The heat there is really severe, 450C on one side, and the other side is -180C and is going from one to the other over a few tens of minutes and the on-board instruments have to operate around room temperature.

So for each orbiter, they have the same problem, but solve it with different solutions.

The Japanese orbiter will spin 15 times a minute to avoid being toasted, like a kebab on a barbecue, while the European orbiter will be wrapped in a special multi-layer blanket and have a radiator for protection.

This will be a really interesting mission to follow.

In the news: 

The search for FRBs is turning up some really interesting results. A new paper from ICRAR is published.


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