Asteroids were born big

Asteroids were born big

How big were the first planetesimals? We attempt to answer this question by conducting coagulation simulations in which the planetesimals grow by mutual collisions and form larger bodies and planetary embryos. The size frequency distribution (SFD) of the initial planetesimals is considered a free parameter in these simulations, and we search for the one that produces at the end objects with a S...

1 5 Ju l 2 00 9 Asteroids Were Born Big Alessandro Morbidelli

How big were the first planetesimals? We attempt to answer this question by conducting coagulation simulations in which the planetesimals grow by mutual collisions and form larger bodies and planetary embryos. The size frequency distribution (SFD) of the initial planetesimals is considered a free parameter in these simulations, and we search for the one that produces at the end objects with a S...

Does being born big confer advantages?

when comparing Aboriginal communities to the majority population, as Wassimi and colleagues point out in their study of perinatal and postneonatal mortality by birthweight. In a step toward understanding the higher infant mortality among First Nations communities, the authors tackled the interesting question of whether there are survival advantages to large-for-gestational-age birthweight. In o...

Planetesimals Born Big by Clustering Instability?

Cardiometabolic Risk Factors in Young Adults Who Were Born Preterm

Adults who were born preterm with a very low birth weight have higher blood pressure and impaired glucose regulation later in life compared with those born at term. We investigated cardiometabolic risk factors in young adults who were born at any degree of prematurity in the Preterm Birth and Early Life Programming of Adult Health and Disease (ESTER) Study, a population-based cohort study of in...