Earth’s orbit is stable, but it does vary over time.
The Possibility Of Planet Nine
There may be a large planet lurking in the outer solar system.
Relative Units
So why did the IAU adopt a fixed standard for the astronomical unit? In the actual 2012 resolution, the possible drift due to the Sun’s mass loss is listed as one reason, but the main reason was the need for self consistent units in the framework of general relativity.
Astronomers Find New Object, Possible Super-Earth In Our Solar System
Astronomers using data from the Atacama Large Millimeter/submillimeter Array (ALMA) have found a distant object in the direction of Alpha Centauri. The object appears to be in the outer region of our solar system, and depending on its distance could be a hypothesized “super-Earth.”
How A Planet’s Distance Affects Its Formation
The distance of a young planet around its star affects the way in which the planet forms.
A Salt On Ceres
When the Dawn probe approached Ceres, it found a striking feature. Was it water ice? A layer of salt? Or something else?
Titan As An Earth-like World
There are many parallels between Titan and Earth, and so we can see the moon as a kind of colder, smaller cousin to our own planet.
Second Time’s A Charm
The Japanese spacecraft Akatsuki has made thrust corrections necessary to put itself in orbit around Venus.
How Many Planets?
Here’s a fun question: how many planets were there in the solar system?