Dec. 2, 2024

#474 Q&A: Constellation Curiosities, Comet Encounters & The Universe's Birthdate

Space Nuts Episode 474 Q&A: Cosmic Constellations, Comet Mysteries, and Citizen Science
Join Andrew Dunkley and Professor Fred Watson as they explore the wonders of the universe in this Q&A edition of Space Nuts. From the shifting...

Show Notes
Transcript

Space Nuts Episode 474 Q&A: Cosmic Constellations, Comet Mysteries, and Citizen Science
Join Andrew Dunkley and Professor Fred Watson as they explore the wonders of the universe in this Q&A edition of Space Nuts. From the shifting constellations as you journey through Space to the enigmatic nature of comets and the age of the universe, this episode is packed with celestial insights and intriguing questions from our audience.
Episode Highlights:
- Constellations from Afar: Discover how the constellations we know would appear from different vantage points in Space. How far must you travel before the familiar star patterns become unrecognisable?
- Comet Tsuchinshan-ATLAS: Delve into the story of Comet Tsuchinshan-ATLAS, its recent appearance in our skies, and the question of whether it has visited our solar system before. Learn about the signs that indicate a comet's history and its journey from the Oort Cloud.
- Age of the Universe: Uncover the methods used to determine the age of the universe, including the role of the Hubble constant and the importance of measuring cosmic distances. How close are we to knowing the exact age?
- Citizen Science Opportunities: Explore the world of citizen science and how you can contribute to astronomical discoveries. From asteroid occultations to light curve data, find out how you can be part of the scientific community.
For more Space Nuts, including our continually updating newsfeed and to listen to all our episodes, visit our website. Follow us on social media at SpaceNutsPod on facebook, X, YouTube, Tumblr, Instagram, and TikTok. We love engaging with our community, so be sure to drop us a message or comment on your favourite platform.
For more Space and Astronomy News Podcasts, visit our HQ at www.bitesz.com.
Become a supporter of this podcast: https://www.spacenutspodcast.com/about
Stay curious, keep looking up, and join us next time for more stellar insights and cosmic wonders. Until then, clear skies and happy stargazing.
00:00 - Space Nuts Q and A edition with Professor Fred Watson
01:29 - Roger asks how far can you go before constellations start getting disoriented
07:45 - Professor Fred and Andrew answer your questions about the Space Nuts podcast
09:13 - On the nights I was best able to observe it, it was cloudy
10:49 - Could this comet be its first visit into the inner solar system
13:47 - How did we measure how old the universe is? Thanks, Fred
19:16 - Sandy asks what is the greatest astronomical discovery by a citizen scientist
✍️ Episode References
Space Nuts Podcast
[Space Nuts Podcast](https://www.spacenutspodcast.com)
New Horizons
[New Horizons](https://www.nasa.gov/mission_pages/newhorizons/main/index.html)
Zooniverse
[Zooniverse](https://www.zooniverse.org)
DreamLab App
[DreamLab](https://www.vodafone.com.au/about/news-centre/dreamlab)
Unistellar
[Unistellar](https://unistellaroptics.com)
Galaxy Zoo
[Galaxy Zoo](https://www.zooniverse.org/projects/zookeeper/galaxy-zoo)

Become a supporter of this podcast: https://www.spreaker.com/podcast/space-nuts--2631155/support.

WEBVTT

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Hi there, it's Space Nuts yet again. How many are

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we up to now? Four one hundred and seventy four?

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My goodness, it's a Q and A edition. My name

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is Andrew Dunkley. Thanks for joining us this time. We

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are going to be answering questions about what constellations look

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like from a different point in space. If you're traveling,

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when when does it not look like your neighborhood anymore?

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It's an interesting question. We're going to talk about a

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comet that's been in the sky recently, and I've seen

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lots of happy snaps from people on the Space Nuts

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podcast group facebook page about this comet, sou Chin Shan.

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We'll also be discussing the age of the universe and

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citizens science. That's all on this edition of Space Nuts.

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Fifteen second Channel ten nine ignition sequence.

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Space Nuts NI or three two one Space Nuts.

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As can I reported, Bills goods and joining.

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Us to answer all of those questions, it is Professor

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Fred Watson. Hello Fred, Hello on.

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Duh, Nice to see you here.

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Very yes, yes, hey you been since I saw you last.

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Sitting here? Really just waiting for something to help?

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Yes, funny that funny? Shall we get stuck straight? Into it.

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We should. Yeah, my coffee is going cold, so we

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should Oh.

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Yeah, yeah, get into that. We are going to New

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York first. This is a question from Roger.

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Roger truck driver. And then I'm traveling through the around

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Back Park in Upstate New York. I got a question

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about the constellations. I'm guessing that anywhere in our solar

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system you went, they pretty much looked the same. But

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how far would you have to go before things start

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to get disoriented? We were to we were to go

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to Alpha Centaur, like four light years away, would just

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still recognize some of them? Are? Would they be completely disoriented?

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And I'm kind of thinking of like science fiction shows

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where they show the stars flying by like trees when

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you're going down the road. I'm kind of guessing it

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wouldn't look like that because of the distance between them.

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They probably look like they stayed in the same place.

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But now the question is how far can you go

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before I think, before you don't recognize the neighborhood anymore? Right,

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loving the show, guys, keep on trucking.

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There he is. Thank you, Roger. I always love that.

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I haven't heard from Roger in a wall. Yeah, that

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was an interesting analogy about driving down the highway and

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the trees fly past. They do portray space travel that

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way with the stars, but I think it would probably

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be a much more boring viewed in that in real

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terms after a while, I mean, it'd be pretty extraordinary

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to look at, but eventually you'd be saying, oh, yeah,

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there it is, the stars still there. Yeah, and what

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check it in the thousand years time and see where

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it is. It might be a bit like that.

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It probably is actually. I mean, for first of all,

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we you know, on human timescales, with the technology that

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we have today, it takes a long time to get

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even beyond the little bit of Pluto as we know

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from New Horizons, which I think took nine years to

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get from Earth to Pluto on its epic voyage in

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the early part of this century. And it is interesting

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that that that has been used as a baseline to

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directly measure the distance to some of the stars. The

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fact that we know where star is from the Earth,

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and yeah, you get to what is it, thirty thirty

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astronomical units something like that. The distance out to Blueto

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it's thirty forty and an astronomical unit is one hundred

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and fifty million kilometers the distance from the Earth to

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the Sun. To get a view from there, their positions

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look very, very slightly different. You need to measure them

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accurately with the kind of equipment that New Horizons has

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on board. But yeah, you can see the difference there.

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You can see what we call the parallax, the distant

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the different position in the sky that a star looks

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to be from different things. Yes, in the name of

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a well known book by an author who has a

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voice very similar to the one that you're not listening

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to now, but you will be in a second.

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I think I know him. Yes, it just happened. It

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does happen to have a copy of the book on

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my desk. As you mentioned you were.

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Yeah, yeah, it's a great, great word and a great

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title from book. But you know, Roger's comments are right

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on the money. You've got to go a long way

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before the constellations start looking different. I think if you

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went to Alpha Centauri, you look at the sky and

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think that's pretty well the same sky that we see

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from except actually for except for you know, the Alpha

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Centauri itself, of the Alpha Centauri systems is a triple

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triple star system that would look pretty damn bright, and

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so you wouldn't really see the stars of Centaurus. But

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a lot of the stars in the sky are at

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distances which you measure in hundreds of light years. I

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guess with the naked eye we see out to about

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very roughly a thousand light years, and so traveling just

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for four and a bit light years is not going

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to change things that much. There'll be some constellations that

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will have the odd star looking as it's in the

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wrong place, and said Norris will be one of them,

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because you're right next to one of the stars of Centaurus.

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But I think generally speaking, you will be able to

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recognize them. They might look just slightly walked, but you're

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able to recognize them. It was certainly a common feature

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of textbooks that I used to read on astronomy when

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I was a youngster growing up and getting interested in astronomy.

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It's a common feature to have pictures of constellations as

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they are now, as they would be in ten thousand years,

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as they will be in fifty thousand years, and you know,

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and so it goes on. And that's because of the

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intrinsic motions of the stars themselves. It's not because we're

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changing our vantage point, but it was always the same.

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You could see the basic outline of a constellation and

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it would just change slightly sort of, you know, you

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realize that it's not quite the same, that something's a

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bit different about it. So I think that will be

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what you'd see as you journeyed deeper and deeper into space.

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Yeah, so you'd have to go a heck of a

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long way before yeah, really sort of went where the

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hell am I?

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Yeah?

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I think I think fifty light years a hundred light

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years you would start seeing a completely different set of

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you know, set of star patterns. You really would worry

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where you were. This would be a very alien sky

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to you.

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Yes, yes, indeed, a really interesting question. And that's brilliant

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and you know, not surprising that it's come from Roger,

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who spends a lot of time traveling and he probably

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is driving along in the trees were flashing past, and

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he went, wait a minute, yep, there's a question in that.

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So there it is.

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Thank you, Roger, Well done, Space MUDs. Our next question

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comes from Lisa. Lisa is from Prince George in British

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Columbia in Canada. Hello, Professor Fred and Andrew. I was

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lucky enough to have clear skies to comet. I'm going

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to get it right this time. Soo Chin Shan was

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passing by. He was passing by and got to observe

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it two nights in a row. I shared a few

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pictures on the Space Nuts podcast group Facebook page. If

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anyone is interested, I probably saw them, Lisa, I did too. Yeah,

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witnessing such a rare event was truly awe inspiring, and

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it got me thinking. We know this comet has an

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orbital period of eighty thousand years, but do we know

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for sure that it's been here before. Is it possible

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that it dropped out of the oort cloud more recently

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and is on its first lap, so to speak? Is

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there any way to tell other than direct observation if

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a comet is a repeat visitor. Thanks for a wonderful podcast.

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I've been listening since twenty eighteen and love of both

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the show and the community that has formed around it. Lisa, Oh,

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that's lovely, Lisa. I'm glad you're enjoying being part of

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a space nuts podcast group on Facebook. And if you're

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not yet, maybe you should go along and have a look,

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because it is a great little page. And yeah, I

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think everyone really enjoys there, their time there and their

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company and the conversation they have with each other. However,

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we have an important question to answer with Sue Chin

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Shan the comet that was in the sky recently on

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the nights I was best able to observe it. It

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was cloudy, and then when it finally cleared up, the

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darn thing was too low on the horizon for me

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to get a look at it, so I never ever

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got to see it myself, which I'm very disappointed about.

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But I'm pretty sure it won't be the last one

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to pass by in the next several years, so I

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might get a shot at another one.

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Oh you will. And I've got a similar story to you, Andrew,

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which is that when it was at its brightest in

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the evening sky here in Sydney, we had really overcust weather,

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which we've got now it's been like this for a

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month and it's not very conducive to astronomy. But I

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was lucky enough when we were I think I told

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you we were many. Now we're down at a place

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called Sea Lake near Lake Tyril in northern Victoria for

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a star fest, and there were lots of telescopes there,

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and one of them had his. One of the astronomers

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who was using these telescopes had his telescope coupled to

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a detector, a real time detector, in other words, a

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TV camera, and he was showing the results on a

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screen and he was actually pointing it at Tushin Chan

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Tu Chin Shan, and so I did see it, but

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not through the telescope, but I saw it live as

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it was on the screen. So that cheered me up

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quite a lot. Now to Lisa's question, that's a really

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good one as well. And this business of the eighty

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thousand years, it's a little bit of a moveable face

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because comment often their orbits are perturbed strongly by the

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gravity of other objects in the Solar System, including in

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particular the planet Jupiter, which is the biggest of the planets,

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and so often the orbital period of these very long

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period comets changes. Now to the nub of the question,

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could this be its first visit into the inner Solar System?

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I think it could be. I'm not sure in this case,

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and I should have read up on this, because there

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are markers in a comet's emissions when it gets near

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the Sun that give you some idea as to how

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many times it has been around the tracks, in other words,

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how many times it's passed close by the Sun, because

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it changes the structure of the comet. Every time it

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goes around the Sun. You get more of the volatiles

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blown away and you're left with a more dusty body.

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And I think think there's you know, the rate at

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which these chemicals, the elements within and molecules within the

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comets I see body, The rate at which these are

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dispersed into space changes depending on which compound you're talking about,

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And so I think by looking at the mix of

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chemicals that is being emitted by a comet when it

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gets near the Sun, you can get some idea of

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how many times it's visited the Sun. Now, I'm only

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saying things that I recall from having looked this up

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a long time ago. So there might be nuances in

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that that aren't correct, and there might also be details

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that I haven't really explained. But at the bottom line

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is that it may have been the first time around

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the Sun. If not, we might have ways of knowing

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about it, and I should check them out just to

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see what the pondits say. About that.

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Yeah, well I was only discovered last year's.

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Right it was, so it was on its incoming orbit

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last year, so we know the first thing.

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I just did a quick search. And now I've said,

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has the commet been here before? And it says it

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has never reached the inner solar system in human his

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view before? Now apparently, so there you are. So it's

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call for it.

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It's a pristine comet, isn't a thought?

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Okay, So we just have to wagit eighty thousand years

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to have another look at.

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It and see what's changed.

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Yeah, yes, indeed there's a few that are going to

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be quicker than that's that's the good news. Thank you,

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Lisa Tho. Really good question, and yeah you're right, it's

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the first time it's been here. Apparently. This is Space

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Nuts with Andrew Dunkley and Professor Fred Watson, the road.

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Piece Nuts.

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Now Fred to our next question, although we're not moving

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far around the globe because this one comes from David

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who happens to live in Canada.

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Hello Andrew and Professor Watson. David here from Saint John's

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Nufuna in Canada, just wondering how did we measure how

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old the universe is Thanks love forcast.

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Thanks David. I'm going to ask David a question that

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every time I travel and I tell people I'm Australian,

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they'll say, oh, do you know John faith Waite? Oh, David,

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do you know Lisa? Now I gather from the provinces

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they live in. They're probably not very close.

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Together at all.

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But you know, I get that. You get that a lot.

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I get that a lot when I travel. It's ridiculous. Well,

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I might know him, except there are thirty million other

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people that you know. Ah, yeah, it's funny. It is funny.

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Ah to the universe. How do we know it's right?

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How did we measure it in the first place? What's

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the goss there?

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So? Yeah, So the first measurements made of the age

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of the universe were when we started measuring what's called

256
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the Hubble constant, And the Hubble constant is the current

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rate of expansion of the universe. It's how fast it's

258
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expanding now. And it's an easy calculation to go from that.

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If you assume the expansion has been constant throughout the

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history of the universe, it's an easy calculation to go

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from the expansion velocity back to when everything was at

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the same point in space, and you get the answer.

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You get an answer of about if I remember this,

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about fifteen billion years. So that was the first way

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that we evaluated the age of the universe. And I

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guess that was in the early sixties seventies when the

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Big Bang theory was really becoming very much the theory

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of the universe as we know it rather than one

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that was just a hypothesis. And so that's the first way.

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But there are there are other ways of doing it,

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and we can you can sort of again it comes

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to it's all about accurately measuring distances and things of

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that sort, because that's what you need to do to

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get a good idea of well, first of all, the

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hubble constant. You've got to you've got to evaluate what

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that is, and it needs the measurement of distances. And

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there are two ways of measuring distances in this kind

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of context. One is standard rulers and the other is

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standard candles. So standard candle is is a light source

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that you hold up whose intrinsic brightness that you know,

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and then you see how bright it is from your

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vantage point. And if you know the intrinsic brightness, you

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can work out the distance, and that's how the super

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and ova work works. People are doing investigation of the

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in fact, in particular the dark energy and the accelerated

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expansion of the universe. They look at super and ova

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explosions of a particular type that we know has a

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certain brightness, and from that you can deduce the supernova's distance,

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and from that you can tell whether your value of

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the Hubble constant is right or whether it needs tweaking.

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And the standard ruler method actually goes back to the

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early universe when there are characteristic separations of galaxies, and

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even before that, the characteristic separation of the hot and

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cold features, of the warm and cool features in the

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00:17:35.480 --> 00:17:40.039
cosmic microwave background radiation give you an idea about the

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you know, the age of the universe, the state of

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the universe at that time. So all these things come

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together and you've got a much more subtle value for

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00:17:48.720 --> 00:17:50.480
the age of the universe. We now think it's thirteen

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00:17:50.480 --> 00:17:53.720
point eight billion years, but that's not that different from

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00:17:54.079 --> 00:17:59.400
just taking a straightforward, you know, linear expansion since zero

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00:18:01.079 --> 00:18:04.880
to determine the age of the universe from the hob

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directly from the Hubble constant, So thirty point eight billion years.

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00:18:08.480 --> 00:18:11.079
It's got a lot of input into it, but even

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00:18:11.119 --> 00:18:13.240
the crudest method gives us something similar to that.

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While you were talking, I thought I'll do a Google

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00:18:17.039 --> 00:18:21.759
search and I asked what is the exact age of

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the universe? And the answer was interesting. According to estimates,

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the universe is thirteen point seven billion years old with

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an uncertainty of two hundred million years. We can't really

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00:18:33.839 --> 00:18:35.039
be exact, can we.

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00:18:36.160 --> 00:18:41.759
No, that's right, so our technology has to improve. I

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have always had not a theory, but the notion that

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when we do get down to the exact age of

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the universe, it will turn out to have been created

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on the first of April, and that will tell us

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things about the universe that we probably don't really want

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to know.

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If it's just one big joke, yeah, oh, how are

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00:19:05.799 --> 00:19:06.160
you loved?

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Yes?

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Imagine So so there it is. David several ways of

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00:19:12.079 --> 00:19:14.359
making the measurement, and they all come up with around

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about the same number. Finally, Fred, we have a question

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00:19:19.759 --> 00:19:24.359
from Sandy. I love these short form questions. Hi, Fred

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and Andrew, are there citizens science programs that you know

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00:19:28.119 --> 00:19:32.559
of where average people I e. Me help with scientific

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00:19:32.720 --> 00:19:39.720
data for asteroid occultations, occultations and light curve data submission

329
00:19:39.799 --> 00:19:43.119
for stars and asteroids. Wow, thanks Sandy.

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00:19:45.359 --> 00:19:48.839
Yes, another great question and good on you. Some do

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00:19:48.960 --> 00:19:52.839
that means you're making measurements, and citizens science is a

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00:19:52.880 --> 00:19:56.039
great way of getting those measurements into our knowledge base.

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00:19:57.599 --> 00:19:59.440
So the first thing that came into my mind was

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00:19:59.839 --> 00:20:04.880
the universe, and Zuniverse is a kind of suite of

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00:20:05.000 --> 00:20:09.279
citizen science programs that started, I think with the Galaxy

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00:20:09.480 --> 00:20:14.079
Zoo project, which was citizens science citizen scientists looking at

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00:20:14.160 --> 00:20:18.720
images from the Sloane Digital Sky Survey, and that's a

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00:20:18.920 --> 00:20:23.599
telescope in New Mexico that surveyed the northern sky in

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00:20:24.119 --> 00:20:27.359
very great detail. Discovered all these weird and wonderful objects,

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and they are among them galaxies, I mean, the weird

341
00:20:32.920 --> 00:20:36.000
and wonderful galaxies is probably what mostly this was about,

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00:20:36.039 --> 00:20:40.960
hence the name Galaxy Zoo, which produced some quite extraordinary discoveries.

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Hanni's object is one that comes to mind. I think

344
00:20:45.319 --> 00:20:48.799
we might have mentioned that recently, a green blob next

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00:20:48.839 --> 00:20:52.799
to a galaxy, which was eventually traced to gas fluorescing

346
00:20:53.359 --> 00:20:56.160
after an outburst from the center of the galaxy probably

347
00:20:56.160 --> 00:20:57.960
are burnt by the black hole at the center of

348
00:20:58.000 --> 00:21:01.400
the galaxy some millions or even billions of years ago.

349
00:21:02.200 --> 00:21:05.559
Haney's vote. It was called because I think that's the

350
00:21:06.559 --> 00:21:10.039
Dutch word for objects, and she was a Dutch school teacher,

351
00:21:10.319 --> 00:21:13.880
which probably still is. So that sort of thing was

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00:21:13.920 --> 00:21:16.680
a particular version of cities and science, but that sort

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of spread its tentacles and became something called the zuniverse,

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which I think has a number of different projects in it,

355
00:21:25.079 --> 00:21:28.680
and I think there may well be they may well

356
00:21:28.759 --> 00:21:34.160
be asteroid occultation you know pages or like data like

357
00:21:34.240 --> 00:21:38.680
curve pages. I actually just googled cities and Science asteroid occultations.

358
00:21:39.200 --> 00:21:43.720
They came up with a number of interesting websites. Unistella

359
00:21:43.799 --> 00:21:48.480
has one Unistellar Citizen Science. Unistellar is a company that

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00:21:49.759 --> 00:21:55.079
is actually manufactures a very particular kind of telescope, and

361
00:21:55.359 --> 00:21:59.759
they have an asteroid occultation citizen science page. That's one

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00:21:59.799 --> 00:22:03.759
to look for. I also googled light curves, I think

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00:22:03.839 --> 00:22:06.440
cities and science like curves. That came up with a

364
00:22:06.480 --> 00:22:11.920
whole lot of things. One of them is it's actually,

365
00:22:12.519 --> 00:22:15.480
you know, the Hubble telescope has global cities and science

366
00:22:15.559 --> 00:22:20.319
projects of its own. But zooly versus perhaps the classification

367
00:22:20.480 --> 00:22:23.720
that's biggest and perhaps most popular, and they certainly do

368
00:22:23.920 --> 00:22:30.720
have a variable star like curve citizen science project. There

369
00:22:30.799 --> 00:22:34.759
are specialist astronomical societies that do both of those things,

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00:22:34.799 --> 00:22:40.640
as well as societies dedicated to asteroid observations and dedicated

371
00:22:40.720 --> 00:22:44.720
to variable star work. Most of them are international and

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00:22:44.880 --> 00:22:47.039
very well established, and they're not that hard to find.

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So have a look around, Sandy, and you're sure to

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find the right one for you.

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00:22:52.200 --> 00:22:54.759
Oh yeah, I thought I'd just throw one out there

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00:22:54.839 --> 00:22:57.680
and say, you know, what is the greatest discovery by

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00:22:58.079 --> 00:23:01.119
astronomical discovery by a citizen sign scientists? And it went

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00:23:01.599 --> 00:23:05.440
straight to an August twenty twenty four article in fiz

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00:23:05.559 --> 00:23:11.039
dot org Citizen science projects identify twenty new astronomical discoveries

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00:23:11.039 --> 00:23:18.359
and that included previously unidentified supernovae. And there's more than

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00:23:18.400 --> 00:23:22.079
two thousand volunteers across one hundred and five countries that

382
00:23:22.200 --> 00:23:26.039
are working on these projects. The project is called Killer

383
00:23:26.119 --> 00:23:33.759
Nova Seekers, and they're aiming to find kilo novae, the

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00:23:33.880 --> 00:23:37.640
explo cosmic explosions of neutron stars and black holes colliding

385
00:23:37.720 --> 00:23:40.640
in distant galaxies. So there's all sorts of stuff going

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00:23:40.680 --> 00:23:43.759
on out there. If you've search deep enough, you'll find

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00:23:43.799 --> 00:23:46.920
what you're more in terms of citizen science in the

388
00:23:47.119 --> 00:23:50.960
realm of astronomy. So yeah, there's a lot going on.

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I don't do it with astronomy, but I do do

390
00:23:55.519 --> 00:23:58.079
a little bit of a thing that's not I don't

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00:23:58.079 --> 00:24:00.920
suppose you call it citizens science. So I downloaded an

392
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app called dream Lab d am Lab, and what it

393
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does is at night, when I put my mobile phone

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00:24:10.839 --> 00:24:14.240
on a charger, I open up the dream Lab app

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and I just click start session and it starts crunching

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00:24:17.920 --> 00:24:21.680

#474 Q&A: Constellation Curiosities, Comet Encounters & The Universe's Birthdate

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#474 Q&A: Constellation Curiosities, Comet Encounters & The Universe's Birthdate

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