Don't Launch Any Sun Missions Today

At 11.27pm UK time tonight, due to it's elliptical orbit, the Earth will be at its aphelion which means it will be as far away from the Sun as it is going to get, 94.5 million miles or 152.1 million km.
The closest (perihelion) was in January and since then the Planet has shifted away by 3 million miles or 4,800,000 km from the Sun than when at its closest so you would think that as our little ball of rock is 3 million miles further out, it would be cooler but apparently it doesn't quite work like that.
As the Earth is on average 93 million miles away from the Sun, the 3 million miles is too small a distance to make a difference to the amount of the Sun's energy we receive, ranging from a 1.5% rise at its closest to a 1.5% dip when it is farthest away.  
A secondary consideration is that the Earth is predominantly water and water has a higher heat capacity than land so the water to land ration offsets the meager solar increase or decrease by the shifting Earth.
Obviously being the furthest point away it is the very worst day of the year to launch a mission to the Sun and not much comfort for the nations currently frying under a heatwave but the movement between Earth and Sun is all part of the elegant dance of Space objects and who doesn't love that.