This year Seder night will include a total Lunar Eclipse. It begins at 2 AM when the edge of the moon first enters the amber core of Earth’s shadow. This video from 2011 has a nice explanation of the what, how and why and Michael Zeiler’s field guide to the total lunar eclipse of 2014 is a simulation of what the coppery-red moon will look like.
I searched for a special prayer that might be added to the Seder to acknowledge this eclipse and found that Hebrew word for eclipse Likui means defect. The Talmud states that because a lunar Likui is a bad sign for Israel (a solar eclipse is even worse as a bad omen for the entire world), an eclipse does not have a blessing.
But in today’s world, we know that the eclipse is not a defect. It is a beautiful act of nature. Here is the perfect addition for your Seder: the blessing for a nature wonder or phenomena:
Barukh attah Adonai eloheinu melekh ha-olam osei ma’asei vereisheet
Blessed are You, The Infinite One, Who reenacts the works of creation.
Barukh attah Adonai eloheinu melekh ha-olam shekocho ugevurato malei olam.
Blessed are You, The Infinite One, Whose power and might fill the world.