we would die
stars
If the sun were the size of a human eyeball then Earth would be the size of a grain of fine sand.
An average blue giant is about 5-10 times the size of the Sun and are much hotter than the Sun is. If our Sun were a blue giant, life, as we know it would never have happened. The Earth would have been vastly too hot to support abiogenesis.
If the earth got pulled in closer to the sun, or if the sun expands significantly, then the earth will get much warmer. That said, nothing like that is going to happen for a couple billion years yet.
we would probably die
The orbit would increase in size (the planet would orbit farther from the sun).
It would melt.
stars
If the sun will be close to earth, earth's temperature will increase. It will be too hot.
If the sun will be close to earth, earth's temperature will increase. It will be too hot.
It's a similar star in most respects to our Sun, slightly larger, but the increase in size, would probably be offset by an increase in revolution. So probably not much. It might be a little warmer and the years should be shorter, but in all other aspects - life would go on as normal.
If we were as big as the sun, we accually would be fine. Did you know that we actually give more heatout than the sun. It's true! the size we are, we don't take up enough room to give out that ammount of heat. So when the sun comes close to the earth, just invent a size ray to get millions of times your size.
It is a very unlikely scenario but if it were to happen, that poor planet would be vaporized by the Suns' immense size and power. If there were to be a planet that was bigger than the Sun then both of them would be vaporized or the Sun would survive but be severely damaged and might explode because of the impact.
If the sun were the size of a human eyeball then Earth would be the size of a grain of fine sand.
About 1 million earths would fit in the sun if the sun were hollow. If Earth was the size of a basketball, the sun would be as big as a basketball court.
If the sun's surface became much hotter while the size remained the same, it would emit more ultraviolet light due to its higher temperature. However, it would still emit a significant amount of visible light, as the sun's overall radiation output would increase with the temperature but would not completely shift from visible to ultraviolet light.
An average blue giant is about 5-10 times the size of the Sun and are much hotter than the Sun is. If our Sun were a blue giant, life, as we know it would never have happened. The Earth would have been vastly too hot to support abiogenesis.