Explore the vast range of titles available.

Oxygen fugacity is a measure of rock oxidation that influences planetary structure and evolution. Most rocky bodies in the Solar System formed at oxygen fugacities approximately five orders of magnitude higher than a hydrogen-rich gas of solar composition. It is unclear whether this oxidation of rocks in the Solar System is typical among other planetary systems. We exploit the elemental abundances observed in six white dwarfs polluted by the accretion of rocky bodies to determine the fraction of oxidized iron in those extrasolar rocky bodies and therefore their oxygen fugacities. The results are consistent with the oxygen fugacities of Earth, Mars, and typical asteroids in the Solar System, suggesting that at least some rocky exoplanets are geophysically and geochemically similar to Earth.

Astronomers have discovered thousands of planets outside the Solar System 1 , most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During the red giant phase, any close-orbiting planets will be engulfed by the star 2 , but more distant planets can survive this phase and remain in orbit around the white dwarf 3 , 4 . Some white dwarfs show evidence for rocky material floating in their atmospheres 5 , in warm debris disks 6 – 9 or orbiting very closely 10 – 12 , which has been interpreted as the debris of rocky planets that were scattered inwards and tidally disrupted 13 . Recently, the discovery of a gaseous debris disk with a composition similar to that of ice giant planets 14 demonstrated that massive planets might also find their way into tight orbits around white dwarfs, but it is unclear whether these planets can survive the journey. So far, no intact planets have been detected in close orbits around white dwarfs. Here we report the observation of a giant planet candidate transiting the white dwarf WD 1856+534 (TIC 267574918) every 1.4 days. We observed and modelled the periodic dimming of the white dwarf caused by the planet candidate passing in front of the star in its orbit. The planet candidate is roughly the same size as Jupiter and is no more than 14 times as massive (with 95 per cent confidence). Other cases of white dwarfs with close brown dwarf or stellar companions are explained as the consequence of common-envelope evolution, wherein the original orbit is enveloped during the red giant phase and shrinks owing to friction. In this case, however, the long orbital period (compared with other white dwarfs with close brown dwarf or stellar companions) and low mass of the planet candidate make common-envelope evolution less likely. Instead, our findings for the WD 1856+534 system indicate that giant planets can be scattered into tight orbits without being tidally disrupted, motivating the search for smaller transiting planets around white dwarfs. A giant planet candidate roughly the size of Jupiter but more than 14 times as massive is observed by TESS and other instruments to be transiting the white dwarf star WD 1856+534.

While she agrees that it makes sense to consider gender dynamics in terms of her biography, Tower thinks that gender should be left out of the discussion of instrumental music itself. Larsen said of her development as a composer, \"I began to think that it didn't matter what pitches I chose, if I could capture the ear and the soul of the listener through the use of rhythm.\" The piece was composed for his funeral service, so Larsen did her best to write a piece of music that captures the fleeting, flowing nature of love and the different types of love we can experience during our lives. Caroline Hartig, now professor of clarinet at The Ohio State University, commissioned this piece from Larsen.

The intrinsic oxygen fugacity of a planet profoundly influences a variety of its geochemical and geophysical aspects. Most rocky bodies in our solar system formed with oxygen fugacities approximately five orders of magnitude higher than that corresponding to a hydrogen-rich gas of solar composition. Here we derive oxygen fugacities of extrasolar rocky bodies from the elemental abundances in 15 white dwarf (WD) stars polluted by accretion of rocks. We find that the intrinsic oxygen fugacities of rocks accreted by the WDs are similar to those of terrestrial planets and asteroids in our solar system. This result suggests that at least some rocky exoplanets are geophysically and geochemically similar to Earth.

In this work, exoplanet-research is combined with the study of the solar system in order to assess differences and similarities between rocky bodies in the Milky Way. To evaluate rocky bodies outside of the solar system, I utilize optical spectroscopy to study polluted white dwarf stars, dense stars that show accretion of planetary material. By observing polluted white dwarfs, we can measure elemental abundances from the rocky and icy bodies that previously orbited the star. Specifically, I conduct observations using the KAST Spectrograph on the Shane 3-meter telescope at Lick Observatory and the High-Resolution Echelle Spectrometer (HIRES) on the Keck I Telescope, as well as evaluate compiled literature data. Generally, the elemental compositions of extrasolar planetesimals closely resemble those of rocky bodies in the solar system. In this work, a more detailed comparison with solar system meteorites and planets shows that oxidation of planetesimals prior to planet formation is common among extrasolar rocks. Overall, the processes that lead to the geochemistry and much of the geophysics of Earth is normal compared to the current sample of extrasolar planetesimals. Additionally, the origin of excesses in spallogenic nuclides in polluted white dwarfs is investigated. The MeV proton fluence required to form the high Be/O ratio in the accreted parent bodies of two polluted white dwarfs (GALEX J2339-0424 and GD 378) is consistent with irradiation of ice in the rings of a giant planet within its radiation belt, followed by accretion of the ices to form a moon that is later accreted by the WD.

[...]juries must rely on physical evidence — security camera footage, DNA testing, and fingerprint analyses — as well as continuities in the stories of multiple witnesses. A recent report found that over 70,000 rape kits have gone untested in the United States, becoming part of what is being referred to as the “backlog.” Because testing is not mandated by law, it is left to the sole discretion of the police force. The Innocence Project, a litigation group that works to exonerate the innocent with DNA evidence, has documented 334 cases of DNA leading to the release of a person convicted of a sex crime from prison. Since the discovery of a backlog, many cities have worked to eliminate it. While many college campuses use a lower standard of preponderance of the evidence — it’s more likely than not that the sexual assault occurred — they are private institutions that can only deprive the accused the privilege of a private education, not the right to liberty that this nation holds dear.

Mike Huckabee echoed Carson’s views, harping on the fact that a police officer ultimately stopped the shooter with a gun. [...]multiple Democratic senators who had previously supported gun rights decided to reverse their positions after such gruesome events. [...]Umpqua, the site of the most recent college shooting, actually allowed students to carry guns on campus. [...]being a Republican has become equated with supporting gun rights. Since 2000, liberals have seen a slight increase of 2 percent (from 26 to 28) in support of gun rights.

\"Barring the discovery of a viable alternative that could feasibly guarantee health insurance for economically-disadvantaged Americans, this tax is the only option.\" Prominent economists cite health care as “eating away at” wages, which have shown no real growth since the 70s. Barring the discovery of a viable alternative that could feasibly guarantee health insurance for economically-disadvantaged Americans, this tax is the only option. Hillary Clinton carefully equivocated on the issue before finally coming out against the tax just days ago.

Hillary Clinton, arguably the most popular current Democratic candidate, has not yet experienced such a disruption, maybe due to the fact that her events are less open than Sanders’. Paul’s struggle to gain in the polls is indicative of the main challenge to a shift towards a more race conscious Republican Party: the primary elections. [...]in order for a Republican candidate to even have the chance to gain the support of the majority of African Americans, they must win the primary first, where black voters are almost nonexistent.

We present evidence that excesses in Be in polluted white dwarfs (WDs) are the result of accretion of icy exomoons that formed in the radiation belts of giant exoplanets. Here we use excess Be in the white dwarf GALEX J2339-0424 as an example. We constrain the parent body abundances of rock-forming elements in GALEX J2339-0424 and show that the overabundance of beryllium in this WD cannot be accounted for by differences in diffusive fluxes through the WD outer envelope nor by chemical fractionations during typical rock-forming processes. We argue instead that the Be was produced by energetic proton irradiation of ice mixed with rock. We demonstrate that the MeV proton fluence required to form the high Be/O ratio in the accreted parent body is consistent with irradiation of ice in the rings of a giant planet within its radiation belt, followed by accretion of the ices to form a moon that is later accreted by the WD. The icy moons of Saturn serve as useful analogs. Our results provide an estimate of spallogenic nuclide excesses in icy moons formed by rings around giant planets in general, including those in the solar system. While excesses in Be have been detected in two polluted WDs to date, including the WD described here, we predict that excesses in the other spallogenic elements Li and B, although more difficult to detect, should also be observed, and that such detections would also indicate pollution by icy exomoons formed in the ring systems of giant planets.