As we noted a few times this month, a lunar eclipse is happening soon and while lunar eclipses occur twice a year, this is the first time on the Winter Solstice since 1554 A.D.    The second most popular question we get about lunar eclipses (First being "Is it safe to look at?  Answer: "Yes") involves the reddish color - people want to know why the moon looks red during a lunar eclipse.

First, the basics: A lunar eclipse happens when the moon, Earth, and the sun all line up with Earth in the middle.     It is an eclipse because Earth's shadow is cast onto the full moon which dims its surface. 

Skin cancer is the most common form of malignancy in the United States and the American Cancer Society has estimated that 1 million new cases of melanoma and non-melanoma skin cancer were diagnosed in 2009, while 8,650 deaths were attributable to melanoma skin cancer.

Studies have supported a positive association between increased use of indoor tanning and both melanoma and non-melanoma skin cancers but the indoor tanning industry is still growing rapidly, with more than $5 billion in annual revenues and more than 30 million patrons - mostly women.

Despite the data, few tanners, male or female, mention avoiding tanning beds when asked about ways to reduce skin cancer risk.

Researchers say they have identified a natural substance in dairy fat that may substantially reduce the risk of type 2 diabetes. The compound, trans-palmitoleic acid, is a fatty acid found in milk, cheese, yogurt, butter and meat but is not produced by the body and so only comes from the diet.

The report explains that trans-palmitoleic acid may underlie epidemiological evidence in recent years that diets rich in dairy foods are linked to lower risk of type 2 diabetes and related metabolic abnormalities.   Health experts generally advise reducing full-fat dairy products but the trans-palmitoleic acid discovery means once again it's better to avoid fad exclusions and diets and simply have a balanced diet in moderation.

580 million years ago, life on Earth began a rapid period of change called the Cambrian Explosion, defined by the birth of new life forms over many millions of years that ultimately helped bring about the modern diversity of animals.

While fossils can help palaeontologists chronicle the evolution of life since the Cambrian Explosion, drawing a picture of life during the 3 billion years before the Cambrian Period is challenging because the soft-bodied Precambrian cells rarely left fossil imprints; early life forms did leave behind one abundant microscopic fossil, DNA. 

Scientists have studied human brain samples to isolate a set of proteins that accounts for over 130 brain diseases and found an intriguing link between such diseases,  the leading cause of medical disability in the developed world, according to the World Health Organization, with an economic costs in the USA exceeds $300 billion, and the evolution of the human brain.

Researchers say they have uncovered a clue that may help to explain why the earliest evidence of complex multicellular animal life appears around 550 million years ago, after atmospheric oxygen levels on Earth dramatically rose, from 3% to the modern day level of 21%.

The group says humans share a method of sensing oxygen with the world's simplest known living animal, Trichoplax adhaerens, suggesting the method has been around since the first animals emerged around 550 million years ago and helps us understand how humans sense oxygen and how oxygen levels drove the very earliest stages of animal evolution.