Both are stars. Other than that, not much: R136a1 is a Wolf-Rayet star, and is both the most massive and the most luminous star known, making it quite different to our Sun. Its large mass (and corresponding high energy output) also make it relatively short-lived.
R136a1's heat would probably vaporize all of the planets.
R136a1 is the brightest known star. VY Canis Majoris. Its bolometric luminosity is estimated at 8.7 million times that of our Sun. VY Canis Majoris has a bolometric luminosity estimated at 450,000 that of the Sun, which is still very powerful. Bolometric luminosity refers to the entire radiation emitted at all wavelengths (not only visible light), so it is a measure of the power emitted by the star.
As far as mass goes, R136a1 beats out VY Canis Majoris by 253 solar masses (265 solar masses for R136a1 vs Canis Majoris' 30). However, VY Canis Majoris beats out R136a1 in radius by about 1,385 solar radii (Canis Majoris is 1,420 solar radii vs R136a1's ~35).
Most stars in the universe are main sequence stars. These stars are in a stable phase of their life cycle where they generate energy through nuclear fusion in their cores. The Sun is a main sequence star.
As the question specifies brightness, the brightest star in the Universe is our Sun - because it is the closest star to us. The most luminous star is another question: See related question.
R136a1's heat would probably vaporize all of the planets.
R136a1 is a blue hypergiant star located in the Large Magellanic Cloud. It is estimated to be approximately 265 times the mass of our Sun, making it one of the most massive stars known in the universe.
R136a1 is the most luminous at about 8,700,000 times more than the Sun. VY Canis Majoris is only 450,000 times more luminous than our Sun.
R136a1 is one of the hottest known stars, with surface temperature around 50,000 degrees Celsius (90,000 degrees Fahrenheit). Its extreme heat causes it to emit intense ultraviolet radiation and it is a supergiant star, approximately 250 times more massive than the sun.
No. R136a1 is in the Tarantula Nebula, in the Large Magellanic Cloud, in the constellation Dorado
there are many stars larger than the sun. for ex. vy canis majoris, the largest star known, rigel, sirius, r136a1 etc.
R136a1 is the brightest known star. VY Canis Majoris. Its bolometric luminosity is estimated at 8.7 million times that of our Sun. VY Canis Majoris has a bolometric luminosity estimated at 450,000 that of the Sun, which is still very powerful. Bolometric luminosity refers to the entire radiation emitted at all wavelengths (not only visible light), so it is a measure of the power emitted by the star.
r136a1
R136A1 Don't know about the size, but I imagine its pretty big
It is R136a1 and has an absolute magnitude 10 million times brighter than our sun
As far as mass goes, R136a1 beats out VY Canis Majoris by 253 solar masses (265 solar masses for R136a1 vs Canis Majoris' 30). However, VY Canis Majoris beats out R136a1 in radius by about 1,385 solar radii (Canis Majoris is 1,420 solar radii vs R136a1's ~35).
Red Dwarf stars. Massive stars are also quite common, but stars like that (e.g. R136a1) don't last very long.