The Gupta Empire is primarily known for its significant contributions to art, literature, and philosophy, not astronomical discoveries. While there were advancements in mathematics and astronomy during the Gupta period, there are no specific, widely accepted "two important astronomical discoveries" attributed to them.

However, here are some notable developments in astronomy during the Gupta period:

* Development of the "Aryabhatiya": This astronomical treatise by Aryabhata (born 476 CE) made several key contributions:

* It introduced a heliocentric model of the solar system, suggesting the Earth revolves around the Sun.

* It provided accurate calculations for the length of a sidereal year (the time it takes for the Sun to return to the same position among the stars).

* It calculated the circumference of the Earth with remarkable accuracy for the time.

* Advancement of astronomical instruments: While specific details are scarce, it's believed that Gupta-era astronomers developed and used more precise instruments for observing the stars and planets.

It's important to note that attributing specific astronomical discoveries to a specific empire or period can be complex. The Gupta period witnessed a flourishing of intellectual activity, and advancements in astronomy were likely built upon knowledge accumulated over centuries.