The orbits of all the planets ( i think) are elliptical. That means they are not perfectly circular. If you google 'elliptical orbits" you
can see examples. Dont be worried about this, its just something that earth and mars do about every 73,000 years.
Here is a solar system viewer. Shows what Im talking about.
Hi there. This is a perfectly normal astronomical event. As Pfiel pointed out planetary orbits are elliptical- Mars particularly so. This means
that some Martian apparitions (i.e. a whole season when Mars is visible in the sky) are closer than others.
As a result Mars can be really bright when it is at it's closest point to the Earth. Due to the elliptical orbit however, some approaches occur when
Mars is at it's furthest point from the sun, on these occasions, Mars may not be much brighter than a brightish star like Aldebaran in Taurus.