#but what about the host planet eclipsing the sun? how often would that happen? would it last long enough to impact daily life?

[sidereon-spaceace]

Today's worldbuilding agonies: not wanting to ever specify how much time is passing because how the hell am I supposed to configure time-keeping across multiple planets and moons across the solar system

But then at a certain point wanting there to be a difinitive countdown clock before Something Bad happens to add tension and stakes

[nasa]

The Stellar Buddy System

Our Sun has an entourage of planets, moons, and smaller objects to keep it company as it traverses the galaxy. But it’s still lonely compared to many of the other stars out there, which often come in pairs. These cosmic couples, called binary stars, are very important in astronomy because they can easily reveal things that are much harder to learn from stars that are on their own. And some of them could even host habitable planets!

The birth of a stellar duo

New stars emerge from swirling clouds of gas and dust that are peppered throughout the galaxy. Scientists still aren’t sure about all the details, but turbulence deep within these clouds may give rise to knots that are denser than their surroundings. The knots have stronger gravity, so they can pull in more material and the cloud may begin to collapse.

The material at the center heats up. Known as a protostar, it is this hot core that will one day become a star. Sometimes these spinning clouds of collapsing gas and dust may break up into two, three, or even more blobs that eventually become stars. That would explain why the majority of the stars in the Milky Way are born with at least one sibling.

Seeing stars

We can’t always tell if we’re looking at binary stars using just our eyes. They’re often so close together in the sky that we see them as a single star. For example, Sirius, the brightest star we can see at night, is actually a binary system (see if you can spot both stars in the photo above). But no one knew that until the 1800s.

Precise observations showed that Sirius was swaying back and forth like it was at a middle school dance. In 1862, astronomer Alvan Graham Clark used a telescope to see that Sirius is actually two stars that orbit each other.

But even through our most powerful telescopes, some binary systems still masquerade as a single star. Fortunately there are a couple of tricks we can use to spot these pairs too.

Since binary stars orbit each other, there’s a chance that we’ll see some stars moving toward and away from us as they go around each other. We just need to have an edge-on view of their orbits. Astronomers can detect this movement because it changes the color of the star’s light – a phenomenon known as the Doppler effect.

Stars we can find this way are called spectroscopic binaries because we have to look at their spectra, which are basically charts or graphs that show the intensity of light being emitted over a range of energies. We can spot these star pairs because light travels in waves. When a star moves toward us, the waves of its light arrive closer together, which makes its light bluer. When a star moves away, the waves are lengthened, reddening its light.

Sometimes we can see binary stars when one of the stars moves in front of the other. Astronomers find these systems, called eclipsing binaries, by measuring the amount of light coming from stars over time. We receive less light than usual when the stars pass in front of each other, because the one in front will block some of the farther star’s light.

Sibling rivalry

Twin stars don’t always get along with each other – their relationship may be explosive! Type Ia supernovae happen in some binary systems in which a white dwarf – the small, hot core left over when a Sun-like star runs out of fuel and ejects its outer layers – is stealing material away from its companion star. This results in a runaway reaction that ultimately detonates the thieving star. The same type of explosion may also happen when two white dwarfs spiral toward each other and collide. Yikes!

Scientists know how to determine how bright these explosions should truly be at their peak, making Type Ia supernovae so-called standard candles. That means astronomers can determine how far away they are by seeing how bright they look from Earth. The farther they are, the dimmer they appear. Astronomers can also look at the wavelengths of light coming from the supernovae to find out how fast the dying stars are moving away from us.

Studying these supernovae led to the discovery that the expansion of the universe is speeding up. Our Nancy Grace Roman Space Telescope will scan the skies for these exploding stars when it launches in the mid-2020s to help us figure out what’s causing the expansion to accelerate – a mystery known as dark energy.

Spilling stellar secrets

Astronomers like finding binary systems because it’s a lot easier to learn more about stars that are in pairs than ones that are on their own. That’s because the stars affect each other in ways we can measure. For example, by paying attention to how the stars orbit each other, we can determine how massive they are. Since heavier stars burn hotter and use up their fuel more quickly than lighter ones, knowing a star’s mass reveals other interesting things too.

By studying how the light changes in eclipsing binaries when the stars cross in front of each other, we can learn even more! We can figure out their sizes, masses, how fast they’re each spinning, how hot they are, and even how far away they are. All of that helps us understand more about the universe.

Tatooine worlds

Thanks to observatories such as our Kepler Space Telescope, we know that worlds like Luke Skywalker’s home planet Tatooine in “Star Wars” exist in real life. And if a planet orbits at the right distance from the two stars, it could even be habitable (and stay that way for a long time).

In 2019, our Transiting Exoplanet Survey Satellite (TESS) found a planet, known as TOI-1338 b, orbiting a pair of stars. These worlds are tricker to find than planets with only one host star, but TESS is expected to find several more!

Want to learn more about the relationships between stellar couples? Check out this Tumblr post: https://nasa.tumblr.com/post/190824389279/cosmic-couples-and-devastating-breakups

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

[jimsturgessnews]

Hi Jim, thanks for sitting down with me and telling me what you’re up to. It will be like a speed date. Yeah, ok. Cool! So, you’ve got Hard Sun on the BBC. Did you watch it when it came out? Yeah, we had a kind of screening. Neil, the writer, who normally lives in New Zealand was here, so we all kind of watched it together. The whole team that worked on it. It was nice. They did food and we had some drinks. We all kind of held on to each other for dear life. Had you never seen it before? I had. They’d done a screening at the BFI on the South Bank, so I keep only seeing the first episode. I’m ready to see the rest now! I still need to sit down and watch all the episodes properly. Is it nerve-wracking? Yeah, It is! I’ve never had the experience of coming out on prime-time TV on that particular slot. It’s a different feeling to when a film comes out. I don’t know why. I think the fact that it has a life longer than the release you know, it has six little mini releases kind of. To be a part of Saturday night TV is quite a big deal for me in England you know. It’s a bit of an institution. Everybody kind of communally watches BBC or Channel 4 or whatever on a Saturday night, so to be a part of that is exciting actually. Everyone watches television in England. It’s true! It’s something you don’t really consider. You make feature films and friends or family are not as interested in the movies and then when suddenly you’re on a television show on a Saturday night, suddenly everyone takes an interest. You’re sort of like: I’ve been doing this for a while now…but in their eyes, you’ve “made it” because you’re on prime-time Saturday night television. Even people I haven’t seen for years or people I went to school with, suddenly everyone is really excited about my new TV show coming out. Nobody ever did that for any of the movies I’ve done. The weirdest I had was people saying: “I saw you on the plane!” and I’m like “why didn’t you say hi?” Ooooh, I was on the plane… The worst I had was when I was onboard a plane once and a movie of mine, a movie called One Day was showing. You’re sitting there seeing it on various screens. You don’t dare get up to go to the toilet. Did anyone recognise it was you? No! I was never recognised. It’s amazing how people don’t associate. I’ve sat next to someone on a plane while they watched a movie that I’m in. You just sit there and you’re like, that’s kind of crazy. I don’t know whether I should say something or not. When a taxi driver asks you what you do, do you tell them you’re an actor? No, most often I don’t. Well, it depends on what sort of mood you’re in. I had a nice one the other day and they always ask you what you’ve been in. And you think, do I have to list what I’ve been in? And he said I never watch movies. Then you list your sort of resume and he’s like no, never seen it. No never seen it. Or yeah, I seen it, didn’t like it. So he ended up phoning his wife and he said “she’ll know who you are!” and he says “I’ve got this fella Jim, what’s you’re surname?” and then she googled me and she said “ooooh yeah! I like him!” so we ended up having a moment. Oh, you just needed a little attention that day, a little interaction. Yeah, I left feeling pretty good. Are you hoping for another season? I am, yeah, for the story. It feels like the show is just getting started really. The concept of the story is that we know the government has withheld information that the world is going to end if 5 years. What happens as this doom gets closer and closer and closer to the ultimate end? I’d like to see more what comes and how human behaviour starts to change as they start to realise what’s happening to the world. It’s so creepy. Yeah, it’s an amazing concept. That’s why I was attracted to it. It’s just the fact that because of a tv show you can spend time looking at the dynamics of people’s lives and their relationships and how they tackle this idea that everything is going to be gone in 5 years and what’s the point of anything? Or do your relationships mean even more? Do they become more vivid and more important? Have you been thinking about that while you’ve been filming? Yeah, a lot. You sort of can’t help it, as it’s such a big topic of the show.  I sort of looked into these documents of people with terminal illness and there are these amazing stories of people who are dealing with the same issues that we’re dealing with on the show. It’s a very personal thing for them when they’ve found out that they only have months or years to live and how they talk and discuss that and how each person’s journey through that was very different. Ultimately everybody said the same thing, which is that you really appreciate those little, beautiful small moments in life. Life becomes very vivid and everything matters. Every relationship you’ve ever had, over time you see, a pigeon fly, you think wow, everything is so incredible, so beautiful and how blessed we are to be here. Do you think that’s affected your daily life since starting the filming? I think you can’t help but have an appreciation for life, yeah, it definitely made me think about that a lot more. To try and right a few of the wrongs and just make sure that everything is in a good place. What an amazing job to have. Yeah, but I sort of think about that stuff anyway, to be honest. And it made me think about space, the cosmos and all that because there’s so much out there that we don’t really understand. The concept of the show isn’t that farfetched. Who knows what’s going on out there that could one day have a huge impact on everything. Well, all the things are happening out there. It’s just whether or not they impact us in this lifetime is a different story. I like the fact that it eclipses our behaviour on the planet. Donald Trump and Kim Jung Un’s behaviour. Nuclear war means nothing when everything’s going to get wiped out and it puts everybody on the same playing field. It’s a very humbling thing actually. When everybody’s going to get wiped out, no one is any better than anyone else. It’s interesting you mention Kim Jung Un because I went to North Korea a few years ago and there they tell everyone the truth, which is that tons of nuclear bombs are being pointed at them by America and at any moment everyone will die. And it really unifies them as a people and it keeps them laser focused and driven and committed to family and country and purpose which was weirdly a by-product that I kind of liked. But that’s basically your TV show in practice. I’m jealous you’ve been. It’s a lifelong dream to see it. You should go! but it would be very annoying to arrive just as they hit the nuclear codes… Oprah’s trying to be the incumbent in 2020, we gotta make some noise and bye bye Jim Sturgess. God Dammit. Then we wouldn’t get a Season 2 of Hard Sun! But you’re finally working in the UK on a TV show, what’s it like to work in the UK vs the States? It was amazing. I’m always on the hunt for something to come out of London. I’m a proud Londoner who lives here and wants to tell good stories out of the city that I come from. But it’s not always easy, so when this came up I was thrilled that it was London based because I love representing London and seeing it on film when it looks great. I could be the host for a change. Normally I’m a guest, but it was nice to be at home and amazing to have London become a giant film set. Now when I walk around I think, I remember filming that down there or that’s where we did that big fight scene. The city becomes this big playground of memories from shooting. And then the opposite of that was when we were filming I’d think, Ah I remember getting thrown out of that pub or being sick down that alley! So, it worked both ways. Speaking of cities that you film in… Berlin I love you? That looks amazing. Yeah, I was excited. I was a fan of the Paris J’tiem films and New York I love you films they did. So, when they asked me to get involved I didn’t really care what the story was and then they figured out what story they wanted me to be in. Was there another story that you wished you were in? I didn’t know what any of the other stories were. They sent me one and it was perfect. I have no idea what anybody else shot, which is kind of exciting. I have no idea how that fits into any of the other stories .And you did the JT Leroy film? Personally, it is my favourite literary farce on the planet! It’s the best thing that has ever happened. Cause you don’t think that happen today. That it could be possible! And I read all the books before it came out. I would have loved to have read those books not knowing and believing there was a 15-year-old boy that had written them. Yes! I believed all of it! Cause I had to read them knowing that this other woman had done it. I mean it was still an amazing read but had I read it through the eyes of a fifteen-year-old boy it would have been quite special. I read all of them and then I went to a reading with Marianne Faithful and the weird fake JT thing with the wig and the stuff and I just felt so much compassion and sympathy for this creature that was so awkward and weird and then the bottom just fell out and I was like “YESSS!!! it got weirder!!!!” I mean, could it have been weirder? It was weird going into the story because when you read about it in all the press cuttings and documentaries, it runs pretty deep. It’s a mental illness that this woman had. It’s a sadness there rather than a practical joke. This woman really struggled with her own identity and really hated the skin that she was born in and wanted to be a young boy with blue eyes. That was her fantasy and how she was able to write through this kid’s persona. It was quite intense cause we hung out with all the people that it happened to a lot when we made the film. Savannah, who pretended to be JT, was on set every day and her brother, who played, was a musician and was a beautiful guy and we spent a lot of time together. There was a real sadness about the whole thing. It was part performance art, part publicity and part mental illness. I can’t wait to see that movie. We had a really fun time shooting it. We filmed it in Winnipeg in Canada and there isn’t a huge amount to do which I like because it really bonds the whole team and you get to know each other very quickly and become a little family while you’re there. The more I learned about the story the crazier it became. The writer pretended to be the manager/assistant to the fake JT Leroy, who was a cockney Londoner, so she put on an accent and called herself Speedy. And had this terrible accent. It’s real, you can’t write that shit. At times it felt like we were making Ab Fab. It was so mental. It was cool cause me and Jeff, who I play, is the movie and is a musician. We wrote a song together, which is a really sweet beautiful song, so we’re hoping that’ll get into the film. But just the experience of writing a song with a character that I’m playing in a movie was so unique for me. For sure. Have you ever met any other characters that you’ve played? In 50 Dead Men Walking, I played an informant who was in hiding, so I wasn’t able to meet him. I was advised heavily not to meet him. Then I played a guy whose family I met and spent a lot of time with. Kidnapping Freddy Heineken, which is a true story about these kids kidnapping the head of Heineken lager. They were trying to figure out a way to get rich and their idea was to put together this heist and kidnap the richest people in Holland. When we were filming, his son, wife, and daughter came to set and it really freaked me out because he died, unfortunately. He was shot many years later by, they believe, his best friend, his wife’s brother. So, it’s all very complicated. But it was intense having them there watching you, dressed as their dead husband or dead father. They tried to make me look like him and I was very nervous about it and felt really uncomfortable about it for the first day. But it was so cathartic for them and they were so lovely and so giving with their time that they ended up coming to New Orleans on a family holiday and came onto set every day. It became a really precious thing for the experience. I became very close to them while we were filming and it was weird to come off set and be able to speak to his wife immediately and say “was that how you imagined it? Was that as real as it felt? Give me info about what happened in that moment.” That’s so intense. But once I was at peace with it and relaxed about that whole idea and comfortable around them, then it was a really interesting process. And the son looks identical to the Dad, so it was really freaky. Oh, and the character from 21 came to set a lot. With women on each arm. He was a good guy. He invited me to his wedding. I would have done, but I couldn’t go. You could bring some babes of your own! Right! That movie was about these MIT kids who had learned how to count cards in Vegas. So really, they were nerds at heart who’d made it big. Nerds. Bless em. Bless those nerds who make it big. Bless us who have to deal with the nerds that make it big. It’s so interesting to see what they thought was cool, you know. To see their perception. It was all about VIP treatment. And the biggest suite. Those are the sort of things that don’t, in my mind, make a really interesting and cool person. I guess the thing that makes them really interesting and cool is innately there, right? The fact that they are super smart math geniuses… that’s what I find cool. But then that’s there anyway, so what do you do about that? It’s boring if you don’t progress. You’re a musician. What kind of music do you write? It depends who I’m writing with and what friend is around that I’m collaborating with at the time. It’s produced in the way that Massive Attack is produced or bands like UNKLE or Primal Scream. Slight sort of electronic vibe with a grounded in guitar as well. But it’s not rock music at all. I was always interested in beats. I never had a rock phase. I grew up listening to 90’s hip-hop music. Here in London? Yeah, my older brother was just a massive hip-hop fan. Then I discovered bands like The Charlatans and The Stone Roses and that led me towards a more English guitar, but it was because of The Beats that led me to those bands. They were English rock, but they still had a groove to them. It wasn’t rock n roll music, it was groovy, Happy Mondays, dance sort of … It’s funny how one band makes it ok to like other types of music that makes it ok to like other types… And then you end up in a genre that you never thought you’d be into, but you’ve been led there slowly by your favourite bands. Musical taste is an intricate part of your personality and your journey through life. I went from Michael Jackson, my first album, then De La Soul, 3 ft high and rising. I was 10 years old and my brother played it to me and I could probably do that whole album lyrically. Then there was a whole hip-hop phase. I then discovered The Beastie Boys when I was skating at 14 or 15 .But they were made for 14-year-old boys. Yeah! I found an identity with them because they sort of looked a little bit more like I did. I don’t look like a member of De La Soul or Public Enemy or whatever. But they were skateboarding like I am… and then I was obsessed with Beastie Boys. I used to do a paper route and my older brother’s friend had left a cassette tape on my kitchen table and I put it on and it was a Charlatans album called Some Friendly. It was the first Charlatans record and I was like “What the fuck is this??” and was like “Oh… Ok.” and then it was like another shift. I sort of identify with them. That sent me down a whole other path. Now I listen to everything. But that was my path. Yes! my cousin had an old boombox that he gave me and he left a blank tape in that he recorded. And there was this Beck album on it and I pushed play and I was like “Whoa. I don’t know what the fuck this is… but I’m into it. THIS is what I like!” I didn’t know what it was for like 6 months and when you’re twelve that’s a long time. There’s a sense of magic to it where you had to find things, or they found you and you were like “What world is this a portal into?!” and then you’d have to find more about it by the record labels and go to the record store and do all the stuff. Now with the internet, you can just tap tap tap and find everything… You had to earn that record… You had to earn your taste. If you knew what it was it’s because you got someone to give you a ride to the record store and sat there all day listening to shit and searching it out… You had to seek it out. You bought it without paying for it. You went home and listened to it with the money that you spent. And that record sounds much sweeter when you paid 10 pounds for it! Exactly. But I still search for that. So I hope that the music I make is hopefully a sort of mismatch of all the music that I like, you know. So far, I’m into it. Well, thank you for speed dating me. I forgot we were even doing an interview. (source)