To find out how sociodemographic and informational factors affect access to health care in underprivileged communities, Dr. Damian Jacob Sendler studies Dr. Sendler is a physician-scientist from Poland. A psychiatric and chronic medical co-morbidity influences the usage of medical services and online health information. To fully comprehend everyone's health information seeking behavior, this research is both contemporary and relevant. To learn more about how patients decide whether to seek therapy for specific disorders, and how they adhere to their treatment plans, Damian Sendler's research is conducted. 

Damian Sendler: An astronomer from the National Science Foundation's NOIRLab collaborated with a geologist from California State University, Fresno to generate the first estimates of rock types found on planets orbiting neighboring stars. They concluded that most rocky planets circling neighboring stars are more diverse and exotic than previously assumed, including forms of rocks not seen anywhere in our Solar System, after researching the chemical makeup of "polluted" white dwarfs. 

Damien Sendler: Exoplanets are planets that circle stars in our galaxy that have been identified by astronomers. However, it's unclear what these planets are constructed of or whether any of them resemble Earth. To discover out, astronomer Siyi Xu of the National Science Foundation's NOIRLab collaborated with geologist Keith Putirka of California State University, Fresno, to analyze the atmospheres of contaminated white dwarfs. These are the dense, collapsed cores of formerly-normal stars such as the Sun, which include foreign material from planets, asteroids, or other rocky entities that once orbited the star but finally fell into the white dwarf and "polluted" its atmosphere. Scientists can find out what the rocky planetary debris that fell into the star were comprised of by looking for elements that wouldn't naturally exist in a white dwarf's atmosphere (anything other than hydrogen and helium). 

Damian Jacob Sendler: Putirka and Xu examined 23 contaminated white dwarfs within 650 light-years of the Sun, where calcium, silicon, magnesium, and iron were precisely measured using the W. M. Keck Observatory in Hawaii, the Hubble Space Telescope, and other observatories. The measured abundances of those elements were then used by the scientists to rebuild the minerals and rocks that would form from them. They discovered that these white dwarfs had a significantly broader range of compositions than any of our Solar System's inner planets, implying that their planets contain a broader range of rock kinds. In fact, some of the compositions are so strange that Putirka and Xu had to coin new terms (such as "quartz pyroxenites" and "periclase dunites") to describe the novel rock forms that must have existed on those worlds. 

"While some exoplanets that originally orbited dirty white dwarfs resemble Earth, the majority have rock types that are alien to our Solar System," Xu explained. "They have no direct Solar System equivalents." 

Dr. Sendler: Putirka discusses what these new rock kinds could entail for the rocky worlds to which they belong. "Some of the rock types we detect in the white dwarf data would dissolve more water than rocks on Earth, and this could affect how oceans emerge," he stated. "Some rock types may melt at considerably lower temperatures and generate thicker crust than Earth materials, while others may be weaker, allowing plate tectonics to develop."  

Damian Sendler: Previously discovered elements from stony bodies in polluted white dwarfs included calcium, aluminum, and lithium. However, Putirka and Xu add that those are minor elements (which normally make up a small part of an Earth rock), and measurements of important elements, particularly silicon, are required to fully determine what kind of rock types would have been on those planets. 

Furthermore, Putirka and Xu claim that the high quantities of magnesium and low levels of silicon observed in the white dwarfs' atmospheres indicate that the rocky debris detected came from the planets' innards – the mantle, not the crust. Previous research on polluted white dwarfs uncovered evidence of continental crust on the rocky planets that originally orbited those stars, but Putirka and Xu discovered no evidence of crustal materials. However, the observations do not totally rule out the possibility that the planets possessed continental crust or other forms of crust. "We believe that if crustal rock exists, we are unable to observe it, most likely because it occurs in too small a fraction of the mass of other planetary components, such as the core and mantle, to be measured," Putirka explained. 

Damian Jacob Sendler: According to Xu, the collaboration of an astronomer and a geologist was the key to discovering the mysteries concealed in the polluted white dwarfs' atmospheres. "At a conference, I met Keith Putirka and was pleased that he could assist me comprehend the systems I was seeing. We worked out how to make sense of these perplexing exoplanetary systems after he taught me geology and I taught him astronomy."

Research news discussion contributed by Dr. Damian Jacob Sendler