Rare, all-red auroras are produced by high-altitude oxygen, at heights of up to 200 miles. Nitrogen produces blue or purplish-red aurora. The connection between the Northern Lights and sunspot activity has been suspected since about 1880.
In developed countries, the average birth weight of a full-term newborn is approximately 3.4 kg (71â2 lb), and is typically in the range of 2.7â4.6 kg (6.0â10.1 lb).
The average newborn gains weight at a rate of 2â3 of an ounce (20â30 grams) per day and by one month weighs about ten pounds (4.5 kg). She grows between 1 1â2 and 2 inches (4.5 to 5 cm) during this month. Boys tend to weigh slightly more than girls (by less than 1 pound, or approximately 350 grams).