If nobody is controlling it, of course it will behave like any large object that hits the atmosphere.
The thread for space cadets!
- Thread starter hobbsyoyo
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First thing - this is not controled ship - good is that everybody knows its location (and will be able to predict ~where it should fall) but thats it.
At that altitude orbital speed should be something around 7 km/s (forgot exact number during last flight on Orbiter simulator - it got real Earth size and something near real-life atmosphere drag..).
Aerodinamic drag is really pulling it down (like 30 km lower orbit height from 175 to 143 in ~24 hrs). In general - if you don't have engines that can slow you down (to decrease your kinetic energy - even to 6 km/s can make big difference) and/or heat shield that can allow to survive de-acceleration phase (even manned space ships heat shield heats up a lot - 1 mistake or leak in heat shield and entire ship like Columbia can be destroyed during atmosphere entry phase), it will burn no matter what - gravity will pull you down, atmopshere will make a lot of drag, transformed in big heat and melting stuff. Only bigger pieces of metal will survive reentry (just because time duration for entire heating stuff is very short). Tried to be short
Thorgalaeg
Deity
Will try to put it even simpler: you need to go very very fast to keep orbiting earth (fast like a bunch of km/s) and you need a huge rocket to reach such speed. That is that rockets are mostly for, since reaching the needed altitude is the easy part. Once in space you have espended all your huge rocket fuel and have not means to reduce your speed, so you will re-enter into atmosphere very very fast and burn due to air friction if you have no shields made of special ceramic materials.
To be able to make a gently reentry you would need to launch a lot more fuel to being able to decelerate, that means a lot more of weight and a much larger rocket to begin with.
To be able to make a gently reentry you would need to launch a lot more fuel to being able to decelerate, that means a lot more of weight and a much larger rocket to begin with.
Berzerker
Deity
Thanks, thats what I was wondering about - so stuff burns up because its simply moving to fast to enter the atmosphere which is moving slower. But even things that can match the orbital speed of the atmosphere still need heat shields?
Thorgalaeg
Deity
No, if you slow down enough you dont need heat protection.
warpus
Sommerswerd asked me to change this
Me and a friend were driving to Toronto on Friday, and saw this weird thin "shadow strip" running across the whole sky vertically. We tried to reason through what it could be, and we couldn't really figure it out. The best thing we have is: "Probably something falling through the sky in a very straight line (which seems plausible), leaving a trail of smoke that blocks out the sun, leaving a weird thin shadow across the whole sky
I was like "Hey that Chinese space station is coming down at some point soon, is that what we're looking at somehow?". I thought it was implausible, and it turns out this was not it at all. But that would have been a good explanation for that weird thing we saw.. maybe
The weirdest part was that this shadow also affected the clouds.. so up in the sky yeah okay there's a weird thin stripe, maybe it's some sort of an atmospheric effect from the sun or whatever, who knows. But when you looked right at the horizon, there were white clouds there, and the shadow covered a thin part of the cloud too. So it basically looked like there was something in between the sun (behind us) and the clouds & everything else in front of us, some sort of a thin & crazy long thing. But when I looked behind me, admittedly it wasn't easy to see because the sun is in your eyes, but I didn't really see anything
I took a picture of this, but I haven't copied it from my phone yet. It's probably some weird atmospheric effect, but I'm just curious what it is. Another weird thing about it was that there was also at the same time an almost rainbow-like perpedicular line running across the sky as well, although it was slightly curved. You could barely see it though and it almost wasn't visible. The dark shadow part was a lot more visible than that, at first I didn't even see the perpendicular thing
I thought maybe it's the windshield but confirmed that it wasn't
I was like "Hey that Chinese space station is coming down at some point soon, is that what we're looking at somehow?". I thought it was implausible, and it turns out this was not it at all. But that would have been a good explanation for that weird thing we saw.. maybe
The weirdest part was that this shadow also affected the clouds.. so up in the sky yeah okay there's a weird thin stripe, maybe it's some sort of an atmospheric effect from the sun or whatever, who knows. But when you looked right at the horizon, there were white clouds there, and the shadow covered a thin part of the cloud too. So it basically looked like there was something in between the sun (behind us) and the clouds & everything else in front of us, some sort of a thin & crazy long thing. But when I looked behind me, admittedly it wasn't easy to see because the sun is in your eyes, but I didn't really see anything
I took a picture of this, but I haven't copied it from my phone yet. It's probably some weird atmospheric effect, but I'm just curious what it is. Another weird thing about it was that there was also at the same time an almost rainbow-like perpedicular line running across the sky as well, although it was slightly curved. You could barely see it though and it almost wasn't visible. The dark shadow part was a lot more visible than that, at first I didn't even see the perpendicular thing
I thought maybe it's the windshield but confirmed that it wasn't
Berzerker
Deity
hmm...so you think maybe you saw the shadow of the station?
could you draw a line following the shadow to the general region of the sun?
its official, it burned up ~8:16 pm est over the S Pacific
now why did they show a horizontal band around my latitude as the likely zone?
could you draw a line following the shadow to the general region of the sun?
its official, it burned up ~8:16 pm est over the S Pacific
now why did they show a horizontal band around my latitude as the likely zone?
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warpus
Sommerswerd asked me to change this
That's what I thought for a while, as a possible yet highly unlikely explanation for what we were looking at. But I looked it up and the station wasn't burning up in the atmosphere for a while still
Think of it as matching the speed of.. the ground. The slower you are moving wrt to the ground, the easier it will be for you to enter the atmosphere without burning up.
If you're orbiting the Earth you are moving very fast wrt the ground. Most ships won't have enough fuel on board to lose all that momentum. You usually enter the atmosphere at a specific entry vector and use the friction the atmosphere will create in order to start slowing down (and hopefully not burning up as you do so)
hobbsyoyo
Deity
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They weren't really looking. If a space bunny had hopped into view of the cameras while they were happening to be taking pictures, they might have seen it. But beyond that they were not very advanced instrument-wise. But that shouldn't be surprising considering how harsh the conditions are on Venus. They were built like tanks and could still only survive a few hours.
Also this. I think that a simple sanity check would be to fly a balloon to Venus and use a microscope to inspect the atmosphere. That should tell you pretty quickly if there are algae-like things living in it. Just open a chamber, let the atmosphere in and turn a microscope on it.
I think you dropped some zeroes - it would hit the atmosphere closer to 26,000 km/h, not 26.
Big pieces can survive but also small pieces if they are made of heat-resistance materials like titanium.First thing - this is not controled ship - good is that everybody knows its location (and will be able to predict ~where it should fall) but thats it.
At that altitude orbital speed should be something around 7 km/s (forgot exact number during last flight on Orbiter simulator - it got real Earth size and something near real-life atmosphere drag..).
Aerodinamic drag is really pulling it down (like 30 km lower orbit height from 175 to 143 in ~24 hrs). In general - if you don't have engines that can slow you down (to decrease your kinetic energy - even to 6 km/s can make big difference) and/or heat shield that can allow to survive de-acceleration phase (even manned space ships heat shield heats up a lot - 1 mistake or leak in heat shield and entire ship like Columbia can be destroyed during atmosphere entry phase), it will burn no matter what - gravity will pull you down, atmopshere will make a lot of drag, transformed in big heat and melting stuff. Only bigger pieces of metal will survive reentry (just because time duration for entire heating stuff is very short). Tried to be short
Yeah but in reality you will never ever have enough fuel to slow down enough that you don't need heat protection. To do that you would need a rocket in space that is as large as the one that put the thing in space in the first place.
The space station is far too small to make a shadow you could see from the ground.
warpus
Sommerswerd asked me to change this
I thought it could have potentially been created by the space station (or some other object) entering the atmosphere. For now that seems like the most likely explanation - that it was some asteroid that streaked across the sky and blotted out the sun in that very straight vertical line. It seems very unlikely still for something like that to happen, but I can't think of anything else this could have been
[facetious reply] I hope you know where your towel is. That could have been a Vogon ship. [/facetious reply]
warpus
Sommerswerd asked me to change this
Here's the photo
That black strip ran all the way up the sky, as far as I could see anyway. It seemed equally narrow everywhere, and perfectly straight
It's a bit faint so for a while we didn't even see it. But when it goes over white clouds it especially stands out like you can see
That black strip ran all the way up the sky, as far as I could see anyway. It seemed equally narrow everywhere, and perfectly straight
It's a bit faint so for a while we didn't even see it. But when it goes over white clouds it especially stands out like you can see
Thorgalaeg
Deity
Probably the shadow produced by the contrail at the top of the photo. You can see similar phenonenon in this space shuttle launch video. Wait till last 30 seconds:
warpus
Sommerswerd asked me to change this
The sun is almost right behind us, we are heading east/north-east-ish and the sun is starting to go down behind us.
Looking at the above video.. I think you guys must be right!
It just looks so weird, because the black shadow looks to be perfectly straight, while the white cloud does not look nearly as perfect. But watching that video has got me convinced that this must be it
I wonder what the perpendicular rainbow-like line was. Probably just some odd atmospheric effect. It's just so weird it looked to be exactly 90 degrees. The whole thing looked like a large cross in the sky heh. Mind you, you could only see it if you really looked, the perpendicular rainbow part was not easy to initially spot. I only spotted it when I started trying to figure out what the black shadow was. It didn't really come out in any of the photos I took
Berzerker
Deity
https://phys.org/news/2014-11-magnetic-fields-frozen-meteorite-grains.html#nRlv
anyone an expert on nebular magnetism?
I wonder if magnetic studies will tell us if this region harbored an early planet
anyone an expert on nebular magnetism?
I wonder if magnetic studies will tell us if this region harbored an early planet
hobbsyoyo
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It definitely tried to have a planet, that's what the asteroid belt is. How far along it got in the accretion process it got is anyone's guess at this point. Though Ceres and Vesta are pretty big so it got somewhat far along - and may have produced even larger planetoids that were later destroyed or eaten by Jupiter. But basically, a planet should have formed and would have formed in the region of the asteroid belt but Jupiter is so fracking huge that it disrupted the process and left us with the asteroid belt which couldn't condense any further.
Ariane 5 returned to flight yesterday and was successful. Virgin Galactic also took their new SpaceShip Two supersonic, so maybe it'll start carrying passengers later this year.
Berzerker
Deity
Phoebe is a target for mining, its a sizeable planetoid that got ripped apart leaving an exposed iron core. I question how Jupiter could have not only formed but grown so large before a planet twice as close to the sun. Jupiter's size is a product of being the 1st planet outside of the solar system's early frost line - where gases (water vapor) blown by the solar wind start condensing. But the asteroid belt is located at the frost line - it is literally divided into a 'wet' outer zone and drier inner zone - so a planet forming there should have been forming before Jupiter. I think Jupiter grew larger during the late heavy bombardment, collisions released a bunch of material and Jupiter was there to gather much of it up.
Berzerker
Deity
https://www.cnet.com/news/dinosaurs...ampaign=Feed:+CNETAsiaBlogs+(CNET+Asia+Blogs)
The rock finished them off but it was beauty that killed the beasts
The rock finished them off but it was beauty that killed the beasts
