Guru Purnima, a tradition followed by South Asian countries like India, Nepal. It is basically dedicated to spiritual and academic teachers, highly revered by Hindus and Buddhists.
“Guru” is a Sanskrit word which means Teacher, Guide or Master. And “Purnima” which is also a Sanskrit word means Full Moon.
A day (TITHI in Hindi) in which full moon occurs dedicated to Gurus.
And
Lunar Eclipse (Chandra Grahan)
When Sun, Earth and Moon all aligned in a single line in which Earth comes in between Moon and Sun and cast its shadows on Moon is known as Lunar Eclipse.
Umbra and Penumbra
These are the shadow regions when the eclipse occurs. Darker part or Inner part is known as Umbra and lighter part or outer part is known as Penumbra.
When Earth cast a dark shadow or completely passes from the Inner part is known as Lunar Eclipse.
And when Earth passes partially from Inner and Outer part and cast half shadow or lighter shadow on the moon is known as Partial Lunar Eclipse.
In the night around 1:30 am to 5:47 am on 17 July 2019 India, as well as the whole world, will able to see Partial Lunar Eclipse.
It is after 149 years, the occasion is coming when Guru Purnima and Lunar eclipse are occurring together.