Earth formed around 4.54 billion years ago by accretion from the solar nebula. Volcanic outgassing probably created the primordial atmosphere and then the ocean; but the atmosphere contained almost no oxygen and so would have been toxic to most modern life including humans.
Euthyroid is the state of having normal thyroid gland function. Examples of a nonfunctioning thyroid gland may be hypothyroidism, hyperthyroidism, or thyroiditis.
Euthymia in bipolar disorder is simply defined as a relatively stable mood stateâneither manic/hypomanic nor depressed. However, some dictionary definitions have shades of meaning that might be confusing in the context of bipolar disorder and similar mental illnesses. To further complicate things, a significant number of euthymic bipolar patients still show some traits of depression.