Questions tagged [temperature]

Temperature is a measurement of the average kinetic energy of the molecules in an object or system. In simpler words: it's the degree or intensity of heat present in a substance or object that is commonly measured with a thermometer.

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How to calculate emission measure from EVE data? [closed]

I am trying to analyse solar flare temperatures from EVE FITS files in PYTHON. All I have are the irradiance values for a range of wavelength at every 10 seconds. I have made clear Gaussian fits to ...
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How to find the temperature of a planet accounting for the atmosphere?

Recently, I started writing a program to generate star systems, and I need a formula to find the approximate surface temperature of a planet. I know of several formulas for this, for example this one ...
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What is the average temperature of all planets at 1 bar?

Jupiter's (and Saturn's) "surface" temperature is defined as that at 1 bar. It is inconsistent to say the other planet's surface is their hard surface. Applying the same measure what is the ...
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How close would a Sunlike star have to be in order to be dangerous to look at it through a spyglass?

Alpha Centauri A which has an about 50% higher luminosity than the Sun is obviously undangerous to look at through a handheld telescope, at about 4.4 ly distance. How close would a yellow dwarf have ...
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What was the energy/wavelength/frequency of the CMB when first emitted/released?

Given the z redshift of 1089, and the temperature difference between then and now of about 1089, I tried scaling the ev, freq. and wavelength by 1089.... Is that right? I get a freq. of about 240 ...
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Will Jupiter eventually stop shrinking?

Jupiter is currently shrinking due to the Kelvin-Helmholtz mechanism. Will this mechanism eventually hold or getting slower? If so, at what size of Jupiter will it stop and why? If not, what will ...
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Would Europa be an ocean planet if it were in the habitable zone?

If a Europa-like body were in the Sun's habitable zone, let's say in an orbit between Earth and Mars, would the body become and remain a water ocean planet? In the habitable zone, the Sun would warm ...
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How does Io's atmosphere behave in volcanic plumes?

Io's surface air pressure is about 0.3 millipascals but Io's atmosphere is strongly variable, depending on whether it's on the near side or far side of Io (relative to Jupiter) and it collapses at ...
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How do I calculate the surface temperature of a star from luminosity? [duplicate]

How do I calculate the surface temperature of a star from luminosity? I've been trying to delve into speculative solar systems for a bit, and I've heard the surface temperature of a star can be ...
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Estimating star temperature

I have an assignment, where I'm supposed to estimate the temperature of a star in at least two different ways, and determine which of the approaches gives the most reliable estimate. All that is given ...
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What is the actual temperature of a quasar?

My daughter asked me last night: What is the hottest thing in the universe? The first thing that sprang to mind was the core of a fresh neutron star (this question agrees: What is the hottest thing ...
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Temperature of a substellar point on an airless tidally-locked planet

If a hypothetical blackbody planet's components were solid at all temperatures, would the substellar point on the airless tidally-locked (1:1) planet eventually heat up to the surface temperature of ...
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Relationship between Color Index and Temperature

Is there an exact relationship between color indices and temperature? I have seen some numerical formulas relating B - V color index to temperature, of the form $B - V = a_1 + \frac{a_2}{T} $ . I ...
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Finding the solar radius from temperature and luminosity

This question has eluded me for days; I can't seem to solve it. A certain star has a temperature twice that of the Sun and a luminosity 55 times greater than the solar value. What is its radius, in ...
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Estimating a star's radius, temperature, and luminosity based on its mass

(See updated figure and description below.) I've been trying to generate ballpark estimates for the radius, temperature and luminosity of stars in the main sequence based solely on their masses (...
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Why is Mars cold?

The surface temperatures of Mars are about -87C to 5C, which is much colder than that of Earth's. If Mars has 95% carbon dioxide, which is a Greenhouse gas, why is the surface of Mars so cold? ...
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Why is our Sun hotter than UY Scuti?

As Wikipedia says the surface temperature of UY Scuti is 3,365 K and the sun is 5,778 K Why is the Sun hotter than a supergiant star like UY Scuti?
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What if the atmosphere of Titan were like the one on Venus?

The current mean temperature in Titan is −180 ºC (93 K), the same as in Saturn. But I was wondering what would be the case if the atmosphere of Titan would be like the Venus atmosphere, whose ...
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Stars that don't fit $L=4\pi R^{2}\sigma T^{4}$?

When calculating luminosity/radius/temperature for several stars, I've noticed that while the majority of stars conform to the luminosity relationship $L=4\pi R^{2}\sigma T^{4}$, there are a few that ...
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Hottest Possible Hydrogen-Fusing Stars

I guess this is more a question about stellar models than anything else. I was wondering what is predicted to be the hottest possible stars that would still be hydrogen-burning. What complicates ...
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Do we know the fluctuations and constant temperature depth of the moon?

Disclaimer: I have no formal scientific training. From what I understand, surface temperature effects on Earth extend only so far into the ground so that at a certain depth the temperature remains ...
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What causes hot temperature extremes?

Recently I looked into the hottest(and coldest, but in another question) natural places. I find this to be a "cloud of searing gas that is surrounding a swarm of galaxies clustered together five ...
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What causes cold temperature extremes? [duplicate]

Recently I looked into the coldest(and hottest, but in another question) natural places. I discover this to be the Boomerang Nebula, with a freezing temperature of about −272.15 °C. Then I looked at ...
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Why would the Chang'e-4 lander find lunar far side temp. “colder than scientists expected”, when the LRO has already been taking thermal readings?

In January, the Chinese probe lander Chang'e-4 was was announced to have found temperatures dipping lower on the far side than expected ("Chinese rover finds lunar nights 'colder than expected'" by R. ...
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Regarding the VizierR catalogue

I want to build a Machine Learning model to approximate effective temperatures of stars based on their B-V index but there aren't that many catalogues that include that. I came across the Vizier ...
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Can Jupiter's nightside be classified as spectral type Y?

As far as I am aware, the latest spectral types that have been assigned are around Y2, for objects like WISE 0855-0714 that have temperatures around 250 K or so. I've also seen several directly-imaged ...
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How to Calculate Planetary Equilibrium Temperature in Binary systems

I'm working on a program that generates the basics stats of a terrestrial planets in binary star systems. I'm not the best at this kind of math, so I'm having trouble calculating the planetary ...
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How to Distinguish between Temperature and Doppler effect using Black-body radiation?

I understand that the radiation of a body can be described using the curve for black-body radiation. In the sense that a hotter body will be blue shifted and a cooler body will be red shifted. The ...
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How much does being at the perihelion heat Earth up?

The author in this article: https://news.nationalgeographic.com/news/2010/07/100707-aphelion-heat-wave-earth-sun-science-weather-nation/ has explained that positional differences on the orbit is a ...
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Why doesn't the equipartition theorem disallow spinning dust?

This excellent answer to the question What is the physics of the “spinning dust” contribution to Cosmic Microwave Background measurements? Is well sourced. The abstract of one of the papers there, ...
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Why the forbidden lines of [OIII],[NII] and [SII],[OII] are sensitive to electron temperature and electron density, respectively?

I am trying to understand the topic of "Metallicity estimates", either HII regions or planetary nebula. For this latter, the electron temperature (and density) must be known. I am studying the ...
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Temperature gradient in stars

It is a well known fact that in stars, there exists a temperature gradiënt. The observational reason is because we perceived spectral lines in the otherwise continuous spectrum of a star. If this ...
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What is Earth's average temperature as a whole? [closed]

I would like to know, what is the average temperature of Earth as a whole planet, not just its surface temperature. Hope the following scenario will make it more clear what I mean: Imagine, that we ...
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Air temperature range recommendation for observations in a summer night with an entry level telescope?

Recent nights where I try to make my first observations with the entry levell telescope Seben with 114 mm mirror it seems that for lenses less than 6 mm details go lost due to warm air refraction (as ...
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Are brown dwarf masses notoriously difficult to measure?

The Next Big Future article Rogue Exoplanet 12.7 times bigger than Jupiter is 20 light years away SIMP J01365663+0933473 has a magnetic field more than 200 times stronger than Jupiter’s. The object ...
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Why is the Warm-Hot Intergalactic Medium (WHIM) so hot, and what is “collisionless shock heating”?

The Phys.org article Researchers find last of universe's missing ordinary matter says: Ordinary matter, or "baryons," make up all physical objects in existence, from stars to the cores of ...
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How can the temperature of stars can be determined by their color?

How do you determine the temperature of a star by color?
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Gaia Gbp - Grp: why does it get larger as star gets redder?

As an enthusiastic amateur scientist, I'm plowing my way through a cool Gaia DR2-based paper, "An Empirical Measurement of the Initial-Final Mass Relation with Gaia White Dwarfs". I'm doing all right, ...
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H-R diagram, Double stars

Can someone help me? I have a case, like, we have H-R diagram and two stars on it. One of them is a blue star on main sequence, another is a red giant. They have equal luminosity. If they are in a ...
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Is there a comfortable part of Venus's upper atmosphere?

I know the surface of Venus is very hot, but that it gets cooler the higher you go in the atmosphere. I have heard that there is a section in the atmosphere of Venus that might be somewhat habitable ...
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What is the temperature under the surface of Mercury?

What is the temperature under the surface of Mercury? I know at the surface the temperature varies greatly (-297 F to 801 F). I also realize that the answer would likely depend on depth. Do we know ...
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What would the pressure and temperature of gas be, right above Jupiter's gas/liquid boundary?

Older pages like this "Exploration of the Solar System" course page describe the transition as being a few hundred kilometers down. More recent findings seem to put the boundary deeper. See The ...
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Venusian polar surface temperatures

I've stumbled across several articles about how the Venusian polar high atmosphere is really cold. What these articles appear to fail to specify is what the surface temperatures of the poles are. I am ...
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Temperature of Earth if tidal locked with the Sun?

Assume the Earth somehow stopped spinning once every ~24 hours, and instead started rotating at ~365 days per rotation, so it effectively would end up being tidal locked with the Sun. In this ...
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Predicting Temperature Variation on Planets with High Eccentricity or Long Diurnal Periods

Whew! That title was a mouth-full, but accurate I hope. What I'm trying to figure out is a model for calculating the approximate temperature variation for a generally earth-like planet (similar ...
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How do we define temperature in outer space?

I was recently reading an article on space.com about : What's the Temperature of Outer Space. They said : Some parts of space are hot! Gas between stars, as well as the solar wind, both seem to be ...
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What contributes the most to the seasonal temperature variation?

The seasonal temperature is ultimately due to the precession of the Earth around the axis. But what I'm curious about is... is it due more to the side experiencing winter being farther from the sun ...
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Calculating star radius from temperature and absolute magnitude - what am I missing?

In an attempt to visualise nearby stars, I've tried to get the star radius (measured in solar radii) using the equation provided on the following site: http://cas.sdss.org/dr4/en/proj/advanced/hr/...
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Why are there no ISM clouds with temperatures between 100 and 6,000K?

In the interstellar medium, there are several different diffuse phases of gas, distinguished by their density and temperature. Specifically, the cold neutral medium has temperatures from ~50-100 K and ...
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Why didn't the Big Bang produce heavier elements?

Shortly after the Big Bang, temperatures cooled from the Planck temperature. Once temperatures lowered to 116 gigakelvins, nucleosynthesis took place and helium, lithium and trace amounts of other ...