We’ve told you about all about VY Canis Majoris, the most sizable star in the known universe. Lurking in the cosmos some 4,900 light-years from earth (about 28.8 quadrillion miles from our home), Canis Majoris is a mammoth without compare. If this star were in the center of our solar system, it would extend far beyond the orbit of Saturn (so let’s be glad that it’s a few quadrillion miles away).
To give you some hard figures, the circumference of our Sun is approximate 2.7 million miles (4.3 million km), while Canis Majoris is approximately 1.9 billion miles (3 billion km). This means that, when circling around the sun, light clocks in at about 14.58 seconds. However, it takes almost 8 hours for photons to travel around Canis Majoris. Plan on circumnavigating this beast yourself? Maybe think again. Of course, it would take generations to reach this star. But even if you were magically transported to Canis Majoris, a passenger airplane traveling along the surface at an average cruising speed of 559 mph (900km/h) would take over 1,100 years to complete one circuit. Which means that, if you started your trip around this star on the day that the Holy Roman Empire was founded (about 962 CE), you would have just finished your journey. A similar trip around our own Sun would only take you 7 months (but you’d probably die from eating the horrid airplane food). Still not impressed? The amount of energy our Sun emits in a year is equal to what this hypergiant releases in the matter of seconds. But Canis Majoris isn’t the only title weight champ in our galactic neighborhood…although it might be the largest, it isn’t the heaviest. Previously, the Pistol Star was the heaviest known stellar object. Measuring in at nearly 150 solar masses, and spanning some 4 light-years, the largest shell of expelled gas from the Pistol star is so big that it could stretch from our Sun to the tips of the next nearest star (Proxima Centaur, which is some 4.2 light-years away). But with a mass that was once 320 times greater than the Sun’s, R136a1 makes the Pistol look like a tiny speck. Discovered early in July of 2010, R136a1 is the most massive known star in our corner of the universe; it also has the highest luminosity. Currently, the star measures nearly 265 solar masses. But when it was born (roughly one million years ago), the star weighed as much as 320 times as much as the Sun. However, heavy stars rapidly lose mass by converting it into energy. R136a1 has already lost 20 per cent of its mass during its short life. The Sun, by comparison, has been burning for some 4.57 billion years, and has converted only 0.03 per cent of its mass into energy. In cosmic terms, R136a1 is still a baby. But, sadly, its life is already drawing to a close. Scientists estimate that stars of this size live only 3 million years. For humans, such a life would be legendary beyond measure…but for stellar hypergiants like R136a1, it’s barely a blip.