Sirius does not orbit the Sun.
No. Sirius is far from a cold star. Sirius is actually a binary system about 8.6 light years away. Sirius A is a white main sequence star just over twice the size of the sun. Sirius B is a white dwarf stellar remnant of about 0.978 solar masses. The temperature of the two stars are far higher than that of our sun. The sun is about 5778 Kelvin, Sirius A is almost twice that at 9,940 K and Sirius B is many times that at 25,200 K.
Sirius A is about twice as massive as our sun, but has a surface temperature of around 10000 degrees Kelvin, compared with our suns surface temperature of around 5800 Kelvin. The Earth and all of the other planets would be a lot hotter if they remained at their current orbit, though the orbits would change as the gravitational pull of Sirius A would be greater. The water on earth would boil off and it would become a barren planet that could not support life. Even Mars may be too hot to support life if Sirius A were our star.
Well, darling, Sirius is about twice the size of our dear old Sun, and the Sun could fit about 1.3 million Earths inside it. So, if we do the math (which I'm sure you could handle), Sirius could fit around 2.6 million Earths inside it. But hey, who's counting? Just know it's a whole lot of Earths.
Yes. Sirius actually consists of two stars. The main object, Sirius A is not only bigger than Earth but is almost twice the diameter of the sun. The secondary star, Sirius B is a collapsed remnant of a star called a white dwarf. It is slightly smaller than Earth but far denser.
From Wikipedia: "The age of the system [Sirius is a double star] is estimated at around 230 million years." So, a fairly young star, at least if compared to typical stars, including our own Sun.
How long does it take for Earth to orbit the Sun? One year, or 365.25636042 days.
The sun does not orbit itself!
Quite simply, the Sun DOESN'T orbit the Moon.
Alpha Centauri does not orbit the sun.
Do you mean how long does it take Mercury to orbit the sun ? 87.969 days
365.25 days to orbit the sun.
A long time.
Ganymede takes about 7.2 Earth years to orbit the Sun once.
It takes approximately 247.92 Earth years for Pluto to orbit the Sun.
Mercury's orbit of the sun takes 87.969 days.
As its further away from the Sun.
Since Callisto is a moon of Jupiter, it orbits the Sun together with Jupiter - and takes just as long as Jupiter to orbit the Sun.