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Transcript below

Dr Ian Musgrave brings us his April SkyGuide … telling us when, where and what to look for in the evening and morning skies this month.
Included are references to the April 8 Total Solar Eclipse transecting diagonally right across continental USA.
As usual Ian gives us his ‘Tangent’ about Fungi on the ISS
Also Ian is continuing his ‘Astrophotography Challenge’ where he presents us with an achievable and challenging task to undertake with our cameras.
This month our challenge is to capture Comet 12P/Pons-Brooks, and this month he gives us great tips to capture this ‘Dragon Comet’ with simple equipment.
Transcript:
Brendan: Welcome to the Astrophiz Podcasts. My name is Brendan O’Brien, and first of all, we would like to acknowledge Australia’s first astronomers, the Aboriginal and Torres Strait Islander people, the traditional owners and custodians of the land we are on. This episode is produced on Yorta Yorta and Kauna Country. And we’d also like you to influence your local politicians to do more to mitigate climate change by moving from fossil fuels to renewable energy sources.
We’re now in our ninth year of production with over 180 fabulous interviews with top scientists from all over the world. Each month we produce two fabulous episodes…. On the first of each month, Dr Ian ‘AstroBlog’ Musgrave gives us his monthly SkyGuide, plus a unique astrophotography challenge. Then on the 15th of each month, we publish an interview with a leading astronomer, astrophysicist, space scientist, data scientist, telescope engineer, project manager, or particle physicist. And we discover their science journey and rare insights into how they think and conduct their amazing research into exactly how our universe works.
Our audio files and transcripts are available on our website at Astrophiz-dot=com and MP3s can be freely streamed from Soundcloud, Google Podcasts and Apple Podcasts.
But right now we’re zooming over to Adelaide in South Australia to speak with Ian.
Brendan: Hello Ian.
Ian: Hello Brendan.
Brendan: Great to be speaking with you again Ian and can you tell us mate, what’s up in the sky for April?
Ian: Well it’s always a pleasure to speak to you Brendan and the month of April has a number of interesting things happening.
Now sadly, most of the bright planets have vanished from our evening sky and Jupiter is scraping the horizon over the next few weeks. But despite that a number of interesting things are happening.
To start off with, once again, Australians will be united in the same time zones in Central Australia and Eastern Australia.
Which also makes telling you about when things happening a lot easier. As always, I’m going to start with the moon. So April the 2nd is the last quarter moon. April the 9th is the new moon. April the 16th is the first quarter moon and April the 24th is the full moon. The moon is at perigee on April the eighth and at apogee on April the 20th.
So Easter is coming up and over the Easter period, we’re going to have a reasonably dark sky so you can go out and look at the pretties and then over the next couple of weeks, you’ll have plenty of dark sky time.
So let’s go back to the evening sky. I’ve already told you that Jupiter is lowering in the northwest evening sky.
It’s getting progressively lower and progressively difficult to see as the month progresses. And possibly by the end of the month, you won’t be able to see it very well at all. On the 10th and 11th, Jupiter’s bracketed by the thin crescent moon lower in the twilight. And you probably will need a lower level horizon to see it at its best. Jupiter and Uranus are within binocular distance of each other.
They’re coming closer over the month but they’ll be very difficult to see in the twilight when they’re at the closest on the 21st. In fact they’re probably only visible in the civil twilight where the background light will make it almost impossible to see Uranus even in binoculars.
So that’s the evening planetary action.
Now let’s look to the morning sky where a lot more interesting things are happening. Having said that, I will say there’s one more interesting thing coming up in the evening sky, but I’ll talk about that later on.
So Mercury returns to the morning sky from about mid -month and at the end of the month will be quite visible. On the 19th, Mercury is two degrees … That’s about two finger widths from Venus, but you’ll probably need binoculars and a level of unabscured horizon to see Mercury.
However, by the end of the month, Mercury is prominent at nautical twilight and it’s making a nice line with Mars and Saturn. Now, obviously, as I’ve just said, Venus is sinking further into the morning twilight and by the end of the month, it’ll be virtually unobservable, so it’s transiting from nautical twilight to civil twilight. It’s sufficiently bright that you can still see it reasonably well at civil twilight, but at least at the beginning of the week as nautical twilight is transiting into civil twilight, the view of the lineup of Mars, Saturn and Venus will look very nice indeed.
So on the 8th, Venus will be above the crescent moon again. This is quite low in the twilight but it will look very nice in binoculars and again as I said on the 19th Mercury is 2 degrees from Venus but you’ll need binoculars to really see Mercury.
Now Mars is still climbing higher in twilight and on the 6th the crescent moon is above Mars so you’ll have a lineup of moon, Mars, Saturn and Venus right there on the horizon, and then Mars and Saturn are coming closer together so Mars is going to be close to Saturn on the 11th and that’s because Saturn is also climbing higher on the twilight so on the 7th remember on the 6th the crescent moon was just above Mars on the 7th the crescent moon is just below Satan so the line up of Mars , Saturn and the uh crescent moon the with Venus down low on the horizon … And again, that’s going to be quite attractive.
As I said, Saturn’s going to be close to Mars on the 11th, but the pair will be less than half a finger width apart. And they’re going to be easily visible together in not only binoculars, but in the medium power telescope you should be able to see the rings of Saturn, as well as the Mars being a disk. So that will be very nice.
So that will be all a photography challenge. The main challenge there is simply getting up at that hour of the morning, rather than a technical photography challenge.
So those are the main planetary action. Now, I remember I said that there’s another thing happening in the evening. This is Comet 12P.
Now Comet 12P/Pons-Brooks is a Halley -style comet and it’s currently entertaining the Northern hemispherians.
We’ve seen some really nice photographs of the comet near the Andromeda Nebula. So it will come into our evening sky around about mid month and it’s going to be reasonably bright now when an astronomer says bright … that means brighter than magnitude about 13.
And typically, many of the bright comets are things that you can only see with a humungous telescope. But it’ll be coming in at around about magnitude 4 .5 will actually get brighter as it rises.
But unfortunately, it’s been going to be very low to the horizon initially. And so even though it’s real magnitude is 4 .5, you’re looking through all this horizon muck, and it will be more like magnitude 5 … so really probably just visible for the unaided eye if you’ve got a good eyesight more likely going to be binoculars. So on the 14th it’s going to be quite close to Jupiter in fact it’ll be within binocular distance of Jupiter because it’s south of Jupiter.
So if you get your binoculars out look at Jupiter and look about binocular diameter to the south, you should be able to see the comet. Now the comet’s going to be … even though it’s relatively bright, that’s magnitude five, which is within unaided eye visibility … but because it’s an extended object and a fuzzy object, it will be a lot harder to see than something of the same magnitude like a star, for example. It continues to grow rise higher in the sky so by the 21st it’s now substantially above the horizon, there’s less murk, it is actually brighter, it’s the magnitude 4 .4. Wow! But it’s close to two of the brightish stars in Taurus, Chai and Omicron. They’re relatively visible as they’re relatively bright stars, very close together. They’re just down from the head of Taurus the Bull, so you should be able to check it out quite easily. So it’s on the opposite side of the horns of the bull, it’s forming the body of the bull. So the shape of the head of Taurus the Bull, you follow that down by a couple of binocular distances, near the head of Taurus the Bull, you should see the pair of the stars that represent Chai and Omicron and on the 21st the comet will be within binocular distance of them.
So I hope that you tell me your binoculars on that and the comet should be visible there in binoculars. You might be able to see it with the unaided eye. Again, that’s going to be higher in the m urk and you’ll have less atmospheric distortion but still because it’s a faint fuzzy object you may not be able to see it very well with the unaided eye. During the rest of the month it gets higher and higher still but now it’s starting to fade unfortunately most of the …. there’s no good signpost stars but if you’ve got your binoculars trained on the pair of Omicron and Chai Tao and sweep up you should be able to pick it up as it goes. And also, if you’ve managed to detect it when it was next to Chai Tau, you should be able to keep on watching it night after night as it goes up.
And as the sky gets darker, it’ll be easier to see even though it’s fading.
Brendan: Okay!
Ian: … And for those of you us who are in the northern hemisphere, waves to northern hemisphere people, if you’re in the United States, you’ll be able to see the total eclipse of the sun on the 8th. That is, if you’ve already booked accommodation a year in advance and booked your plane tickets a year in advance.
If you live close to the line, which goes through Texas, Atlanta, Kentucky. Indiana, Pennsylvania and New York up into Maine and Ohio then you might be able to drive to the center line and watch the eclipse but don’t count on getting any accommodation because all the eclipse fanatics will have booked it out but it’s going to be a very good eclipse.
It’s going to be a nice deep eclipse. So we’ll be able to see it for over three minutes. The best observation is in southern US, north Mexico, but everywhere else we’ll still see a nice duration of eclipse and because the moon is not far from Perigee where it’s closest to the earth, it’s nice and big, it’s a nice big shadow and you should be able to get some very good images of the Corona if you can get there … So that will that will be excellent for our North American listeners If you’ve got a chance and you’re living close have a go if you’re not living close then it’s too late You should have organized yourself much better Hahah Which is what I always say because every year I say “Oh I should go visit this eclipse in somewhere interesting” and I never do.
So there’s one last thing to look at. If you’ve been watching the sky, you’ll be noticing that the Southern Cross has been getting higher and higher.
The last episode, I talked about the Southern Pleiades and the nice little cluster just heading off the Southern Cross. If you train your binoculars on the Southern Cross itself, just below Beta Crucis, you’ll see a nice, nice little sprinkle of stars. This is the Jewel Box and this is one of the lovely sights of the southern skies.
It’s called the Jewel Box because there’s a lot of different coloured stars. It’s small, but it is absolutely beautiful.
Brendan: Yes!
Ian: And that’s it for the sky … There is lots of lots happening, lots to do, but unfortunately it involves getting up very early in the morning.
Brendan: Excellent! What a good thing to do. Okay. Keep going, Ian.
Ian: Okay. Would you like a tangent?
Brendan: I’d love a tangent. The tangents are a highlight for me.
Ian: Okay. Well, next time you’re looking up at the International Space Station or Tiangong as it goes over, and this month around about the middle of April, there should be some nice ISS passes around about mid month, bear a thought for the passengers have made to them.
Now, I’m not talking about the human passengers, but they’re not human ones. So the ISS has played a host to a range of organisms, ants, fish, mice, tardigrades and squid. But all of those have been intentional experiments without taking the organisms up into the the space station to see what microgravity does to them,
or how they respond to microgravity. But I’m talking about the unintentional passengers, much smaller and with greater horribility potential. I’m talking fungi, and also microorganisms,
but mostly fungi. Now, to set the scene, back in ’98, we first learned that fungi could survive in outer space in the… rather dramatic way.
So the Cosmonauts on the Russian space station near saw a strange film spitting across the outside, a window, yes, that’s the outside. And this thing kept on growing,
destroying the windows, titanium quartz surface, and getting into the space station. Are you freaked out yet? This is where we’ve turned on the spooky music. Now, it turned out these space invaders were…
not space invaders, but homegrown fungi that had hitched a ride on the spacecraft and had learned to survive in this vacuum of space. And I tried following up on these particular fungi,
but getting the peer -reviewed papers is very difficult. So I can’t tell you… Actually, I identified them, but I can’t tell you what they are. But anyway. as a result of this we take a lot of care to keep stuff going into space sterile.
So the payloads move through clean rooms, they’ve got high power air filtration systems, they’re thoroughly mopped in the scrum with disinfectants. So the things we take into space are generally at least reasonably sterile.
But you can’t do this to humans, found you grow a human skin, as I’ll do, indeed, other more cross and get into space with this. So even with the best cleaning procedure, there’s still fungi lurking on the space station.
So again, this has horrible potential, but there’s been a long running experiment monitoring the microbiomes of the natural space station. And so far it’s found that the ISS microbiome in the ISS is probably similar to the ISS.
to the urban earth environments. They fluctuate a bit from month to month, but they’re not horribly the similar to the earth environments. That’s the microorganisms,
fungi and bacteria that are living inside the space nation. There are some differences. There’s some rare of yeast that tend to be more abundant and colonized.
the astronauts, but so far it doesn’t seem like anything’s gonna be really toxic. But like Mia, there are microbes that are on the outside of the ISS.
– Yep. – And the researchers have found that microbes have not only survived in these environments, well, we do that from the ISS, but retain their reproductive ability. And most of the work orders exhibit increased biochemical activity and resistance to antibiotics,
which is not such a good thing. So in order to study the response of microorganisms to living in the vacuum of space and the radiation of space,
the European Space Agency has started the Lycans and Fungi experiment to see how fungi behave in space and in Mars -like conditions. Unfortunately, the abbreviation LIPE is the same as the title of a Netflix horror movie about an African -froled life form that start legally looks like an overgrown fungus and takes over the International Space Station with horrifying results.
So, the ESA exposed a lichen to the exterior of Mars -like conditions. of the International Space Station for 18 months. That is over a year. And it survived.
There’s no water, no air, extreme temperature, constant bar -bar radiation. And the lichen didn’t even go into stasis, but it kept right on photosynthesis. You’re true.
This might seem bizarre, but lichens are really radiations of resistance. They can survive something like 12 ,000. ,000 times the dose of a killer human. Not only that,
there’s a fungus called cryptococcus neopholans that actually eats radiation in roughly the same way that plants eat light we think because we still don’t quite understand how it works.
They were discovered inside the reactor at Chernobyl and part of the reason why they’re able to survive annual heat inverted commas. commas are radiation is they produce a huge amount of melanin.
So NASA sent these melanites found in a space in 2016 and then did a long -term experiment from between 2017 to 2018,
looking at whether or not these fungi could not only survive air in space, but could they protect the eye of from radiation?
And they found that the fungi indeed could cut radiation levels on the ISS by about 2%. This was done with relatively small patches of fungi, and they worked out that they had a more comprehensive fungal sheet.
This could cut it down by around about 4%. That doesn’t sound like much, but it still is another layer of security. security reducing radiation hazards on the ISS.
It could be incorporated with other materials to grow a thicket of fungal matter. You don’t have to worry so much about lofting all these materials into space in one go where the fungi can just nicely grow for you,
and it might be also useful in Mars where you could use these fungi to grow inside the Martian structures to help shield the Martian structure from radiation. radiation. So,
one day these microbes might help shield spacecrafts to have that from some radiation. So, even though the bungie in space has the potential to be a type of a horribly de -topic,
it turns out these things may in fact be greatly beneficial and help us and so the spacefaring society. Fantastic,
that reminds me how prescient Nessa and JPL were to crash Cassini into Saturn rather than let it wander around space and potentially deposit its hitchhikers into a moon or somewhere else.
And it also makes me wonder what hitchhikers are on board Voyager 1 and Voyager 2, which sooner or later, possibly later, will eventually reach other star systems and begs the question,
what hitchhikers are doing on the surface of those spacecraft? – Well, both the voyagers and the pioneers before them were extensively sterilized as before.
they went into space. So, hopefully, if anything survived the sterilization process, the extended period in deep space will sterilize anything. On the other hand,
when Bereshet crashed into the moon, it was carrying a load of tardigrades, and tardigrades are notorious for surviving high radiation and dehydrating conditions.
So, the… hoping that the radiation on the moon will have killed any of the tardigrades that survived the crash, if any did. But the space fungus story must suggest that they might be a little bit more resilient and maybe the next moon commoners will find tardigrades on the moon.
Fantastic. Okay, Ian. do you have a astrophotography challenge for us for the month of April? Yes, I do. And guess what?
It revolves around Comet 12p. Now, because everyone’s had a go at stacking images from their simple cameras or phones,
and you’re now familiar with stacking software, it’s time to move out and use it for something different. Now, Comet 12p is a different challenge to Vesta.
Vesta was quite dim and basically on the limit of what you would be able to image with simple point and shoot systems,
but Comet 12p is much brighter, but on the other hand, it’s an extended object, so a star -like object of the same magnitude is easier to image than an extended object because the brightness is more plus now.
And also because the comet is roughly at nautical twilight rather than deep astronomical twilight, you’ve got more background light.
So with best you can go all out, do very long exposures and stack blocks that’s good. of long exposures at the highest possible ASA ISO rating.
With 12p, you’ve got the issue that the background twilight, if you buy too much exposure, the background twilight will overwhelm common 12p.
So I would suggest that rather than doing quite long exposures at ISO 3200, which is what I was using, try something lower like 1600.
Try not to run the exposures for longer than about four seconds, maybe one to two seconds depending on your camera and its response and do a good stack.
So I found for my… my Canon XS, a stack of 30 images was good for bringing up faster. Possibly you can get away with fewer,
but stacks of maybe 10 to 20 images might be helpful. And again, I play around a bit because you’ve got some really obvious guide stars.
stars unlike with Vesta where you had to put around a bit trying to find exactly where the guide stars were and making sure you got in between the guide stars on the 14th for Jupiter and on the 21st for the pair of Chai and Omicron,
Omicron Tauri. They’re easy to see guide stars and fairly easy to focus on some. So have a bit of a play around. Try some different exposure times and different exposure isos in order to get a feel for what’s happening.
Stack away and see if you can pull the comet out against the firelight. Now the images I’ve been seeing from northern hemisphere have been showing some nice quite nice tail.
tails, but again, they’ll be taken under very dark sky conditions We’ll have the able to stack lots of relatively longish exposures to bring out the tail So it’ll be a bit of a challenge to In the water to I like that is an hour sunset and try and pull out the tail against the background sky But it’s a well worth it It’s going to be a new nice little comet and hopefully everybody can get to see it,
not only in binoculars, maybe possibly with the unaided eye who got a good eyesight and hopefully with your cameras you can pick up something very nice.
Fantastic, I look forward to better in. I’ve got a very good view from where I am because I’ve got ocean as my western horizon so I don’t have to worry. worry so much about trees and things getting in the way.
It gives me a quite a bit of advantage but the marine layer things get quite high so it gets effectively so that the extinction of further comet and stars is quite significant even though you’ve got a good distance above the horizon.
So I’ll get to play around and I’ll look forward to seeing the comet and now having to react the same. that, it’s probably going to be weeks and weeks of cloud where I’ll see nothing whatsoever.
Well I’ll be trying that. I’ve got a mirrorless camera that I can attach to a six inch telescope and I’ve also got a 400mm lens I can attach to a DSLR so I’ll be having a good shot at that so wish me luck.
I wish you luck, I wish you clear skies and I’ll horizons. And having said that, the entire southeast of Australia will now be softened for the next month.
Of course. Well, thank you very much. The end astro blog must grave a fabulous preview of what’s up in the sky for April,
a great tangent and an inspiring astrophotography. challenge. I’ll be giving it my best shot. Fantastic and let’s hope some more people are enthused and I don’t know are people able to submit photos to the astrophys Facebook site?
If not, they can submit it to the SunSkywatch site and I can share it from there to astrophys Facebook. people who have managed to get some photos okay.
Excellent well thank you very much and good night mate. Good night and you have a great Easter and hopefully you have time to look at the skies in between all family fun and catch -ups.
See ya. See you later bye. And remember Astrophiz is free and unspoken. but we always recommend that you check out Dr Ian Musgraves’ Astro Blogger website to find out what’s up in the night sky.
And in two weeks, we’re bringing you a wonderful interview from the recent Transience Down Under Conference in Melbourne, Australia, where we spoke with Professor Katie Ocatell,
who is the Associate Professor of Astrophysics and Physics from Melbourne. Melbourne University. Her stellar research and science journeys are sensational.
Katie is an observational astrophysicist whose research focuses on the extreme death of stars. You’ll love this next episode and keep looking up!
