Yes, the Sun is a star, but it’s far from typical

Most of us have heard that the Sun is an ordinary, typical, unremarkable star. But science shows we're actually anything but average. This fragment of the young star-forming region NGC 2014 showcases many stars that are bluer, more massive, and much shorter lived than our Sun.

However, the fainter, redder, less luminous stars are far more numerous, making us wonder just what "typical" truly is for a star. NGC 2014 is also found in the Large Magellanic Cloud: over 160,000 light-years away. Our starry skies make us wonder, “Is the Sun a typical star?” From their earliest beginnings to their final extent before fading away, Sun-like stars will grow from their present size to the size of a red giant (~the Earth’s orbit) to up to ~5 light-years in diameter, typically.

The largest known planetary nebulae can reach approximately double that size, up to ~10 light-years across, but none of this necessarily means that the Sun is a typical, average star. and David Frew, Laboratory for Space Research, HKU In the 1600s, Christiaan Huygens first estimated the brightest star’s distance, assuming Sirius was distant and Sun-like. This image shows Sirius A and B, a bluer and brighter star than our Sun and a white dwarf star, respectively, as imaged by the Hubble space telescope. Sirius A, the main star, is an A class star (as opposed to our Sun being a G class star): twice as massive as the Sun, some ~4000 K hotter than the Sun at its photosphere, and about 25 times as intrinsically luminous as our Sun.

Sirius B once had about five times the Sun’s mass, but is now less massive, as a white dwarf, than its surviving stellar companion. . Barstow (University of Leicester) His result, 0.4 light-years, overlooked significant intrinsic stellar differences. The (modern) Morgan–Keenan spectral classification system, with the surface temperature range of each star class shown above it, in kelvin.

The overwhelming majority of stars today are M-class stars, with only 1 known O- or B-class star within 25 parsecs. Our Sun is a G-class star, along with about 5-10% of total stars. However, in the early Universe, almost all of the stars were O- or B-class stars, with an average mass 25 times greater than average stars today.

This portion of the Hubble image of Arp 143 showcases the new stars (in blue) formed as a result from gas stripping, heating, and shocking in the space between the two main galaxy members. Stars have been forming throughout the Universe over the past 13.6 billion years or so, but the ones that survive today weren’t formed evenly or under the same conditions over all of cosmic history. canton Center for Computational Astrophysics, Flatiron Inst. / UWashington); Processing: Joseph DePasquale (STScI) Although the Sun isn’t a rare cosmic outlier, its properties aren’t exactly typical. Over the course of 50 days, with a total of over 2 million seconds of total observing time (the equivalent of 23 complete days), the Hubble eXtreme Deep Field (XDF) was constructed from a portion of the prior Hubble Ultra Deep Field image.