The temperature at the surface of the Sun (top) is about 6,000 kelvins. The Sun's atmosphere is much hotter. The bottom image shows ultraviolet "light" coming from the Sun's atmosphere. The temperature in that part of the Sun's atmosphere is around 70,000 kelvins.
Click on image for full size
Images courtesy of SOHO (ESA & NASA).
Kelvin Temperature Scale Used in Astronomy
The Kelvin scale is a temperature scale that is used a lot in astronomy. You probably know about the Celsius (or Centigrade) scale, which is part of the metric system of measures. If you live in the USA, you also know about the Fahrenheit scale, which is used in the English system of measures.
Why do astronomers need another temperature scale? On Earth, the temperatures we feel most often are pretty much where water is liquid. A temperature scale that has "reasonable" numbers for "normal" temperatures makes sense for day-to-day use on Earth. For example, Earth's average temperature is around 15° C (49° F). Fifteen and 49 are pretty easy numbers to deal with. It wouldn't be so good if our temperature scale used really big numbers (like 6,437°) or really small numbers (like 0.052°) or negative numbers (like -147°) for normal temperatures. The Celsius and Fahrenheit scales are set up to have "reasonable" numbers for common temperatures on Earth.
Temperatures in space are often much colder or much hotter than we are used to on Earth. Comets and icy moons have temperatures close to absolute zero. Stars can have temperatures of thousands of degrees or higher. The Kelvin temperature scale is good to use for really hot and cold places in space. That's why astronomers and space scientists use it a lot. Other kinds of scientists sometimes use the Kelvin scale too.
Shop Windows to the Universe Science Store!
Our online store
includes fun classroom activities
for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist
are also full of classroom activities on different topics in Earth and space science!
You might also be interested in:
What types of instructional experiences help K-8 students learn science with understanding? What do science educators teachers, teacher leaders, science specialists, professional development staff, curriculum designers, school administrators need to know to create and support such experiences?...more
Liquid is one of the four common states of matter. The three others are gas, solid, and plasma. There are also some other exotic states of matter that have been discovered in recent years. A liquid does...more
Not too long ago, many people thought that comets were a sign that something terrible was about to happen. People didn't understand about how objects in the sky moved, so the sight of a comet must have...more
Triton is the largest moon of Neptune. It is a very odd moon. The poles of Triton are especially interesting. Triton has a polar ice cap at the South Pole. Earth has ice caps at its poles too. On Earth...more
The butterfly effect is a scientist's way of saying that small things can make a big difference. As an example, let's pretend a hurricane has just formed in the the Carribean Sea, southeast of Florida....more
The Kelvin scale is a temperature scale that is used a lot in astronomy. You probably know about the Celsius (or Centigrade) scale, which is part of the metric system of measures. If you live in the USA,...more
Text for this level has not been written yet. Please see the "Intermediate" text for this page if you want to learn about this topic. To get to the "Intermediate" text, click on the blue "Intermediate"...more
Magnetism is one of the main forces of nature. Another force of nature is gravity. Magnetism causes magnetized objects to be attracted to each other. An example of the force of magnetism is the magnet...more