Eris (dwarf planet)

Given the constraints of the request, it appears there might be a misunderstanding or a typo in the topic provided. "Beth midrash" typically refers to a Jewish study hall, while "Eris" is known as a dwarf planet in the solar system. Assuming the intended topic is the dwarf planet Eris, I will proceed with an article focused on that. If "Beth midrash Eris" was meant to be a fictional or speculative topic combining these elements, such content does not exist in recognized sources, and I will focus on the known dwarf planet Eris.

Eris (Dwarf Planet)

Eris is a dwarf planet in the solar system, discovered in January 2005 by a team led by Mike Brown at the Palomar Observatory. Named after the Greek goddess of discord and strife, Eris is one of the largest known dwarf planets in the solar system, comparable in size to Pluto. It is located in the Kuiper belt, a region of the solar system beyond the orbit of Neptune that is populated with many other small, icy bodies.

Discovery and Naming

The discovery of Eris was significant because it was initially thought to be larger than Pluto, which contributed to the debate over what constitutes a planet. This debate ultimately led to the International Astronomical Union (IAU) redefining the term "planet" in 2006 and classifying Eris, along with Pluto, as a dwarf planet. Eris was named after the Greek goddess of discord and strife, reflecting the discord in the astronomical community over its discovery and classification.

Physical Characteristics

Eris is notable for its high density, which suggests a rocky, icy composition similar to Pluto. It has one known moon, Dysnomia, named after the daughter of Eris in Greek mythology. The surface of Eris is extremely cold, with temperatures estimated to be around -243 degrees Celsius (-405 degrees Fahrenheit).

Orbit and Rotation

Eris has an orbital period of about 557 years and follows an eccentric orbit that takes it from 38 to 97 astronomical units (AU) from the Sun. An astronomical unit is the average distance from the Earth to the Sun, about 93 million miles or 150 million kilometers. Eris's rotation period, or day, is relatively fast, completing one rotation every 25.9 hours.

Exploration

As of now, there has been no direct exploration of Eris by space probes. Its distant location and the technical challenges involved make such a mission difficult and expensive. However, observations from Earth-based telescopes and the Hubble Space Telescope have provided valuable information about its size, composition, and moon.

Impact on Astronomy

The discovery of Eris played a key role in the reclassification of planets within our solar system. Its discovery prompted the IAU to define the term "planet" formally in 2006, leading to the creation of the "dwarf planet" category. This reclassification demoted Pluto from its status as the ninth planet and grouped it with Eris and other similar bodies in the Kuiper belt.