Pioneer 11 flew past Jupiter in November and December 1974. During its closest approach, on December 2, it passed 42,828 kilometers (26,612 mi) above the cloud tops. The probe obtained detailed images of the Great Red Spot, transmitted the first images of the immense polar regions, and determined the mass of Jupiter's moon Callisto. Using the gravitational pull of Jupiter, a gravity assist was used to alter the trajectory of the probe towards Saturn.
The study of personality is based on the essential insight that all people are similar in some ways, yet different in others. There have been many different definitions of personality proposed. However, many contemporary psychologists agree on the following defias differentiating the HEXACO model from other personality frameworks. Specifically, the H factor is described as sincere, honest, faithful/loyal, modest/unassuming, fair-minded, VERSUS sly, deceitful, greedy, pretentious, hypocritical, boastful, and pompous. The H factor has been linked to criminal, materialistic, power-seeking, and unethical tendencies.
Trait models have been criticized as being purely descriptive and offering little explanation of the underlying causes of personality. Eysenck's theory, however, proposes biological mechanisms as driving traits, and modern behavior genetics researchers have shown a clear genetic substrate to them. Another potential weakness of trait theories is that they may lead some people to accept oversimplified classificationsor worse, offer advicebased on a superficial analysis of personality. Finally, trait models often underestimate the effect of specific situations on people's behavior.
Traits are considered to be statistical generalizations that do not always correspond to an individual's behavior.
The importance that genetic influences have on personality characteristics can change across a five-year period. Age differences create more variables even within a family, so the best comparisons are found using twins. Twins typically share a family environment called a shared environment because they may share other aspects like teachers, school, and friends. A non-shared environment means completely different environment for both subjects. "Biologically related children who are separated after birth and raised in different families live in non-shared environments." Identical twins separated at birth and raised in different families constitute the best cases for heredity and personality because similarities between the two are due only to genetic influences. Vulnerability was a factor in this study that was taken into consideration regarding the issue of genetic influences on vulnerability. The study concluded that the monozygotic co-twins would be more similar than dizygotic co-twins in change over time. The data concluded that there were no significant differences for either variances between the monozygotic and dizygotic co-twins.
Another current open question is whether genetic influences are important for the likeliness of co-twins to change in the same way over a period of time. A link was found between the personality trait of neuroticism and a polymorphism called 5-HTTLPR in the serotonin transporter gene, but this association was not replicated in larger studies. Other candidate gene studies have provided weak evidence that some personality traits are related to AVPR1A ("ruthlessness gene") and MAOA ("Warrior gene"). Genotypes, or the genetic make up of an organism, influence but don't fully decide the physical traits of a person. Those are also influenced by the environment and behaviors they are surrounded by. For example, a person's height is affected by genetics, but if they are malnourished growth will be stunted no matter what their genetic coding says. Environment is also not completely responsible for an outcome in personality. An example from Psychobiology of Personality by Marvin Zuckerman is alcoholism: Studies suggest that alcoholism is an inherited disease, but if a subject with a strong biological background of alcoholism in their family tree is never exposed to alcohol, they will not be so inclined regardless of their genome.
It is also a question open to debate whether there are genetic influences on the tendency of the co-twins to change, without keeping in mind the direction of the change. Another factor that can be addressed is biological versus adoptive relatives and can be clearly seen in what is a real-life experiment: adoption. This creates two groups: genetic relatives (biological parents and siblings) and environmental relatives (adoptive parents and siblings). After studying hundreds of adoptive families, researchers discovered that people who grow up together, whether biologically related or not, do not much resemble one another in personality. In characteristics such as extroversion and agreeableness, adoptees are more like their biological parents than their adoptive parents. However, the minute shared-environment effects do not mean that adoptive parenting is ineffective. Even though genetics may limit the family environment's influence on personality, parents do influence their children's attitudes, values, faith, manners, and politics. In adoptive homes, child neglect and abuse and even divorce between the parents is uncommon. This noted it is not surprising, despite a somewhat greater risk of psychological disorder, that most adopted children excel, especially when they are adopted as infants. In fact, seven out of eight have reported feeling a strong connection with one or even both of their adoptive parents.