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How does north star look like?

The North Star, also known as Polaris, has been used for navigation throughout history. Its position in the sky makes it an ideal guide for determining which direction is north. But what does the North Star actually look like? In this article, we’ll explore the physical characteristics and appearance of this famous star.

What is the North Star?

The North Star is the brightest star in the constellation Ursa Minor or Little Bear. It’s located almost directly above the North Pole from the perspective of viewers in the Northern Hemisphere. Polaris has an apparent visual magnitude of 2.0, making it the 48th brightest star in the night sky. It’s approximately 323 light years away from Earth.

Polaris is a Cepheid variable, meaning it pulsates and changes brightness. The fluctuations are tiny though, only by about 0.2 magnitudes. So to the naked eye, the North Star appears constant.

Physical Properties

Let’s look at some of the key physical traits of the North Star:

Property Measurement
Distance from Earth 323 light years
Luminosity 1500 suns
Mass 5-6 solar masses
Radius 30-50 solar radii
Surface temperature 6000 K
Constellation Ursa Minor

Some key things to note are that Polaris is approximately 323 light years from Earth. It’s a luminous star, radiating around 1500 times the luminosity of our Sun. And it’s fairly massive at 5-6 solar masses. The surface temperature is a hot 6000 K, giving the North Star a white-blue glow.

Appearance to the Naked Eye

The North Star is readily visible in the night sky. To locate it, look to the northern horizon and find the asterism known as the Little Dipper. Polaris marks the tip of the handle of the Little Dipper.

Under moderately dark skies, the North Star will appear as a modestly bright white star. It doesn’t twinkle noticeably like many other stars. That’s because it’s closer to Earth than most stars visible to the naked eye. The steadiness of Polaris adds to its usefulness for navigation.

Although it’s the brightest star in Ursa Minor, Polaris is only the 48th brightest star overall. So it’s nowhere near as bright as first magnitude stars like Sirius or Arcturus. But it does outshine the other stars in the Little Dipper asterism by around 2.5 magnitudes.

Viewing the North Star Through Binoculars

Using a pair of binoculars gives a better view of Polaris compared to the naked eye. Through binoculars, the pale blue-white hue of the star becomes apparent. The North Star’s color results from its hot surface temperature of around 6000 K.

With binoculars, the subtle variations in Polaris’ brightness may also be detectable. As mentioned earlier, the North Star is a Cepheid variable that pulsates and changes brightness by up to 0.2 magnitudes. But these minor fluctuations can only be observed through precise photometric measurements.

Viewing Through a Telescope

Pointing a telescope at the North Star offers the best views of its appearance. Even a small aperture telescope at low magnification will reveal a steadfast bluish-white point of light. The color contrasts with the typical warmer yellow-white shades of most visible stars.

Sometimes Polaris is described as having a yellowish tinge or citron hue. This is tricky to discern visually, but spectrographic analysis confirms it. The yellow hints are likely a result of the star’s higher metal content compared to the Sun.

With larger aperture telescopes, more details can be seen. There is a small 6th magnitude companion star located 18 arcseconds from Polaris. They form a binary star system, visible as two distinct points of light through amateur telescopes. The main star may also appear oblong due to its rapid spinning and shape distortion.

Angular Size

Although Polaris is a supergiant star, it’s angular diameter is tiny when viewed from Earth. Even when measured by interferometry, the North Star is only about 3 milliarcseconds (3/1000ths of an arcsecond) across. For comparison, Betelgeuse has an angular diameter of around 44 milliarcseconds.

This table shows how the angular size of Polaris compares to other stars:

Star Angular Diameter
Polaris ~3 milliarcseconds
Betelgeuse 44 milliarcseconds
Sun 1920 arcseconds
Moon 1853 arcseconds

As you can see, Polaris is extremely small compared to the Sun or Moon which measure around 30-60 arcminutes across. So although it’s a huge star, the North Star is a tiny pinprick of light to our eyes.


By examining the spectrum of light emitted by the North Star, astronomers can determine its composition. Polaris is classified as a yellow supergiant belonging to the spectral type F7 Ib. This indicates:

  • F-type star with a surface temperature of around 6000K
  • Luminosity class I indicating a supergiant
  • Class b meaning it possesses moderate surface variability

Studies show the North Star is richer than the Sun in elements heavier than helium. In astronomy, these elements are collectively called metals. The abundance of metals distorts the star’s appearance slightly from a typical F-type spectrum.

Specifically, Polaris has a high abundance of the metals europium, gadolinium, and samarium relative to the Sun. The enhanced metallicity is likely a consequence of the star leaving the main sequence and evolving into a supergiant.

Future Brightness Changes

Over the span of human history, the brightness of Polaris has remained relatively constant. But observations over the last couple centuries show a slight declining trend.

Astronomers estimate the North Star has diminished in brightness by about a third of a magnitude in 200 years. And over the next 100 years, it may fall by another few tenths of a magnitude.

In the far distant future, Polaris will increase in brightness again before eventually exploding as a supernova. But its status as the Pole Star will have changed long before then as the Earth’s axial precession alters the celestial pole’s position over tens of thousands of years.


The North Star Polaris has been valued for navigation and orientation across cultures and history. When viewed with the naked eye it appears as an ordinary moderately bright white star that doesn’t seem to twinkle. But telescopic and spectroscopic observations reveal much more about this Cepheid variable supergiant.

Polaris has a high luminosity, mass, and peculiar composition. It also pulsates with a period of about 4 days. While it will remain the steadfast Pole Star for centuries to come, the distant future will bring further changes to the appearance and behavior of this unique celestial navigator.