Planet Jupiter causes the retarded growth of Mars. The red planet could have been 1.5 the mass of Earth and should have been somewhere the size of our planet or Venus. At any rate, Mars contended with one-tenth of the Earth's mass.
A theory suggests that Mars was at the wrong place at a wrong time when the sun formed 4.5 billion years ago. The protoplanetary disk that surrounded the sun distributed when Mars was located in a region where the planet-forming materials were scarce, according to the website Space. Thereafter, Jupiter and Saturn connived to rob Mars even more.
"The Grand Tack" theory suggests that Jupiter and Saturn traversed closer to the sun after their formation. They gradually retreated to their current position after some time. In the process, Jupiter's gravity sucked the materials intended for Mars, Astronotes explained. Those who could have been caught by Mars while traveling in its orbit were lost.
Another theory is known as the "Natural Gap." The same argues that materials adjacent to Jupiter were sucked by its massive gravity, thus, leaving a gap. When Mars formed near Earth's orbital position, it was pushed back to its current location. Since Jupiter already hauled the materials, Mars was left in the puny state.
According to Brazil's Universidade Estadual Paulista researcher Andre Izidoro, it is up for debate if which among the two theories really happened. However, Izidoro reserves the possibility that Jupiter is not a culprit in Mars' fate. He stressed that Mars could have been in its current position from the beginning and it was just a cosmic accident that it is half of Earth's diameter.
Here is a bonus theory; the University of Utah researchers Now Kenyon and Ben Bromley suggest a different explanation about the Mars mystery. The difference is the argument that planets were as is. Jupiter simply cleared the asteroid belt of lighter and smaller materials and has left no crumbs for Mars.
