If getting closer to the sun means it’s gets hotter, would there be a point in space where temperatures would be earthlike?
In: Planetary Science
No, not really. Because in space you can heat up by receiving cosmic rays, but you only cool down by radiating your heat away. There is no atmosphere to conduct or convect heat away. And because there is no atmosphere it isn’t really hot so to speak. You might be heating up but there is no Earth-like condition. If you took off your space suit to enjoy the warmth your wet surfaces would immediately start boiling away due to lack of pressure.
Yes and no. The relevant temperature to us isn’t determined just by the proximity to the sun, but also the makeup of Earth (which absorbs and radiates heat) and our atmosphere. Venus has hotter surface temperature than Mercury, even though Mercury is closer to the sun than Venus, because of what their respective atmospheres consist of. So yes, there is a circle around the sun in which the energy transferred by the sun to an object there would be the same as with Earth, but that’s not really the determinant of whether the place is suitable for human life.
Well, in space there is no temperature, there’s nothing there to have a temperature. Except you.
The light coming from the Sun’s heats you up when it reaches you. The closer you are the more power it has and heats you up faster.
There is a point at which the Sun’s light would balance out your heat loss to match that of your experience on Earth, but it is very far away and not interesting at all. Any potential planet there would be *waaay* colder than Earth though.
Not really, because Earth’s atmosphere does a lot of “smoothing out” of the temperature. Outside of the atmosphere, even just at Earth’s distance, being in sunlight is very hot. The outside of the ISS reaches some 250°F on the side facing the Sun. On the other hand, facing *away* from the Sun is incredibly cold. Rather, there’s nothing insulating you. The dark side of the ISS gets down to some -250°F.
The atmosphere of the Earth reflects a lot of sunlight away and absorbs a ton of the energy before it reaches you. Then, when you’re on the night side, that absorbed energy continues to radiate down (and up from the ground) so that you stay relatively warm. Basically, all of the atmosphere and mass of the Earth protects us from the extremes and keeps us an *average* that is comfortable, and the greenhouse effect bumps that average up to what it is today (59°F). AFAIK, the average outside temp of the ISS is slightly lower.
The question also depends greatly on how reflective you are. If you’re covered in mirrors, you’ll absorb less energy and be cooler. If you’re wearing a suit of vantablack, you’ll absorb way more and be hotter.
So, there’s no single answer, here. Earth is earthlike because of many factors, not just its distance from the Sun – which, contrary to the popular myth, varies quite a bit over even a single year because the orbit is elliptical. There is no single magical sweet spot.
“Temperature” is a fickle thing in the vacuum of space. There’s no air to be warmed or cooled by so we’re talking exclusively radiation absorption and emission.
If you’re just hanging out in space one side of you is getting blasted by the sun and the other side is slowly radiating heat away to the frozen abyss of deep space. To regulate your own surface temperature you’ll have to rotate like a rotisserie chicken.
But yes, for your specific mass and surface reflectivity there is a point in space where you could rotate and maintain an average of a refreshing spring day temperature.
It probably wouldn’t actually feel like that though – the sun’s unfiltered radiation would quickly give you a nasty sunburn. And of course you’d be in a hard vacuum.
Yes, about 1 AU.
(i.e. the distance earth is from the sun)
That’s because what you describe (a point where temperature would be earth like) is exactly what earth is. The planet receives sunlight which is energy, and it heats up the planet. The planet also emits light (in the infra-red) which cools the planet.
Over time, these two will balance (they have to eventually, it’s called ‘thermal equilibrium’), and there is a certain temperature where it balances. We just happen to be balanced at that “earth like temperature’.
For instance, Venus is a lot warmer than earth, Mars is a lot colder.
How all the science works out exactly is extremely complicated, it depends on how the sunlight gets reflected, how it gets absorbed, how it gets emitted back into space, how the entire atmosphere moves and stores energy, how oceans store energy, etc etc etc. On earth “global warming” is exactly how stuff like carbon dioxide in the atmosphere changes the way sunlight gets absorbed (and how that energy gets re-emitted) and it pushes that balanced “earth like” temperature higher. And of course, that causes a LOT of problems.
roughly 1 earth-to-sun distance. I’m pretty sure we’re at the point you’re talking about when you consider the complications of temperature in a vacuum. if you were just floating in space alone then the distance would be closer….but you would be hella dead for other reasons. But if you’re in the safety of an atmosphere on an inhabitable planet with a decent temperature….you’re on earth.
Wouldn’t that be Earth?
Getting closer to the Sun does not directly correlate to being hotter. What does correlate is Solar Power Density. That has an inverse relationship to distance.
Temperature for earthlike refers to temperature of fluid surrounding observer. This hasany variables even on Earth.
Yeah, we call it the “habitable zone”
Of course it matters how bright the star is, how reflective the planet’s surface is (called albedo) and whether or not the planet has an atmosphere
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