NASA has recently tweeted a photo taken by the Curiosity rover which is exploring Mars. The photo features the Martian night sky with a tiny speck which was identified with a pointer as our home planet, Earth.

The picture was taken by the rover six days before it was tweeted. Since Curiosity landed on Mars on 2013, the rover was able to capture images of the Red Planet and these were immediately transmitted back to Earth. However, this photo was the first one having Earth on the background. Curiosity has 17 cameras attached to it along with several other scientific instruments. The last time it was here on Earth was on November 2011 when it was sent off to Mars by a NASA Spacecraft from Florida.

The picture released by NASA, accompanied with a caption saying, "Look Back in Wonder", was "processed to remove the effects of cosmic rays". The rover's "...1st picture of Earth from the surface of Mars" was taken approximately 80 minutes after the sunset on Mars using its "left eye camera", also called the "Mastcam."

However, according to NASA, one does not need any special instrument to see our planet from the surface of Mars. The agency told CNN that if a human being with a normal vision will be able to stand on the surface of Mars, he will easily spot our planet and the moon as "two distinct, bright 'evening stars".

Curiosity has many other tasks that it needs to perform, other than taking pictures. Recently, NASA engineers were faced with the challenge of maneuvering the rover over a sand dune, being very careful as they have lost an earlier rover while it was travelling over a sand trap. Curiosity has to get pass the sand dunes to reach an area referred to by scientists as the Gale Crater. Researchers are postulating that the Gale Crater may have evidences that will support the theory that Mars once supported microbial life.