Sentences with phrase «chemical abundance»

This scaling assumed that brighter Sun ‐ like stars (of similar age and chemical abundance to the Sun) show a decadal ‐ scale activity cycle and are analogous to the present ‐ day Sun, whereas the less bright stars were found to be noncyclic and are analogous to the Sun during its Maunder Minimum state.

This catalogue can be used not only to study chemical abundance patterns of the Galaxy but also to train data driven spectral approaches which can improve the abundance precision in a restricted dataset, but also full APOGEE sample.

Targeting bright giants, the method allows to obtain simultaneous age and chemical abundance information far deeper than would be possible with asteroseismology, extending the possible survey volume to remote regions of the Milky Way and even to neighbouring galaxies like Andromeda or the Magellanic Clouds already with present instrumentation, like VLT and Keck facilities.

For the first time, Bergemann's team presented detailed chemical abundance patterns of these halo stars using the W. M. Keck Observatory on Maunakea, Hawaii.

Volker Bromm, a theoretical astrophysicist at the University of Texas, Austin, says rapid rotation «could also lead to a special class of energetic supernova explosions called hypernovae, with unusual chemical abundance patterns.»

These stars make good candidates because they preserve their chemical abundance at the time of their formation.

This discrepancy has cast constant doubt about one of the methods which has been most used to measure chemical abundances in the universe.»

As it sidled up to the planet, Galileo sent a probe into the atmosphere that measured temperatures, pressures and chemical abundances.

Solar twins are the most similar to the Sun, as they have very similar masses, temperatures, and chemical abundances.

For decades astronomers have been on the hunt for so - called «solar twins» — stars with the same ages, masses, temperatures, luminosities and chemical abundances as our own sun.

«The analysis of chemical abundances is a very powerful test, which allows, in a way similar to the DNA matching, to identify the parent population of the star.

He worked with Professor Patrick Young's group to learn how to analyze stellar spectra to find chemical abundances, and inspired by the scientific results, he created two digital paintings of possible unusual extrasolar planets, one being Tau Ceti for his Barrett Honors Thesis.

The fundamental observations that corroborate the Big Bang are the cosmic microwave radiation and the chemical abundances of the light elements described in the Big Bang nucleosynthesis theory.

The motions of the planets have been well established for centuries, the chemical abundances in their atmospheres have been analyzed more recently and the changes in their structure, atmospheres and physical appearance have been noted with repeated observations from ground - and space - based observatories.

These extended, cool and hence red stars are key targets for stellar evolution studies as well as galactic studies for several reasons: a) many stars go through a red - giant phase; b) red giants are intrinsically bright; c) large stellar internal structure changes as well as changes in surface chemical abundances take place over relatively short time; d) red - giant stars exhibit global intrinsic oscillations.

Deriving chemical abundances patterns of these stars is paramount to piecing together the structure of the Milky Way.

While the derived chemical abundances have been shown to be precise for most stars, some calibration problems have been reported, in particular for more metal - poor stars.

In this paper, we aim to (1) re-determine the chemical abundances of the APOGEE+K epler stellar sample (APOKASC) with an independent procedure, line list and line selection, and high quality surface gravity information from astroseismology, and (2) extend the abundance catalogue by including abundances that are not currently reported in the most recent APOGEE release (DR12).

This large collection of chemical abundances allows for a more copacetic understanding of stellar compositions, without bias towards a given group or technique.

Currently the team is concentrating on extrasolar planet discovery and characterization, precision measurement of stellar chemical abundances, and precise mapping of the Milky Way and of large - scale cosmological structure.

Not exact matches

The Cocozia ® organic coconut water has a natural abundance of potassium, magnesium, and other electrolytes to satisfy your body's chemical needs.

Google it for an abundance of recipes and to get rid of chemicals in your house.

Ongoing studies at Uppsala University in Sweden have shown that the chemical agent dubbed Pittsburgh Compound - B, or PIB, is a highly accurate marker of plaque buildup and that its abundance in the brain can predict whether patients with mild cognitive impairment will develop Alzheimer's — and when that decline will likely start.

Regolith X-ray Imaging Spectrometer (REXIS)-- A student experiment provided by the Massachusetts Institute of Technology (MIT) and Harvard University in Cambridge, which will observe the X-ray spectrum to identify chemical elements on Bennu's surface and their abundances.

Instead, scientists gauge OH abundance by looking to proxies — chemicals that react with hydroxyl.

Measuring the abundance of each chemical in so many stars is an enormous challenge.

Huygens will sample methane in the atmosphere and measure the relative abundance of light hydrogen and heavy hydrogen to produce a chemical fingerprint that will enable scientists to compare Titan's composition with that of comets.

They determined the stars» chemical content by studying their colors and divided them in two main groups according to their heavy - element (iron) abundance.

Study co-author Nuno Santos, an astrophysicist at the Center for Astrophysics at the University of Porto in Portugal, and his colleagues took chemical - abundance data, derived from precision light spectra, on 133 stars of roughly sunlike temperature from the HARPS survey, 30 of which are known to harbor planets.

Measurements of surface chemical composition, either by direct sampling (as has been done on Earth, the moon, and Mars) or through spectroscopic observations, can be used to estimate elemental abundances and the degree of chemical differentiation that occurred as the planets condensed from the solar nebula.

When comparing the chemical compositions of these stars with the ones found in other cosmic structures, the scientists were surprised to find that the chemical compositions are almost identical, both within and between these groups, and closely match the abundance patterns of the Milky Way outer disk stars.

The hybrid material combined the advantages of each component: an abundance of edges where chemical reactions take place and excellent conductivity between GQDs provided by the graphene base.

It will also study solid and gaseous samples for other chemical signs of past or present life, such as a very high abundance ratio of methane to heavier hydrocarbons (ethane, propane, butane) and chirality (a preference for either left - handed or right - handed organic molecules).

Although some non-biological chemical reactions can create such high light - carbon ratios (McCollom and Seeward, 2006), those found were so skewed towards Carbon - 12 that it's unclear exactly how such reactions could have created such abundances.

The relative abundances of the chemical elements provide significant clues regarding their origin.

In addition to variations in chemical composition — both because of the initial abundances and the star's evolutionary status, [34] interaction with a close companion, [35] rapid rotation, [36] or a magnetic field can also change a main sequence star's position slightly on the HR diagram, to name just a few factors.

Yet, the full star formation and enrichment history of a galaxy can be traced directly only if two key observables can be determined... ▽ More Red giant stars are perhaps the most important type of stars for Galactic and extra-galactic archaeology: they are luminous, occur in all stellar populations, and their surface temperatures allow precise abundance determinations for many different chemical elements.

A spectrograph spreads out the light gathered by a telescope so that it can be analyzed to determine such properties of celestial objects as chemical composition and abundances, temperature, radial velocity, rotational velocity, and magnetic fields.

«The abundance of some chemical elements in the stars in the external regions of the Milky Way halo — explains Giuseppina Battaglia, astrophysicist at the IAC and first author of the article — was found to be surprisingly different from the information we had concerning the inner regions of the halo».

The SAD is laden with many foods that are counterproductive to producing vibrantly healthy babies: foods such as damaged fats (those overheated and extracted with solvents), commercially raised meats (if any meat is consumed at all, as many fall victim to the deception of vegetarianism), and an abundance of pesticides and chemicals via conventionally farmed foods, fast foods, processed ingredients, body care products, cleaning supplies and municipal water sources.

While cruciferous vegetables such as cabbage and broccoli are rich in many essential nutrients, they are distinguished for their abundance of chemical toxins called glucosinolates.

Isn't it just common sense to see that the «western diet's» lack of an abundance of whole, unprocessed, plant based foods - and also the fact that meats and processed foods can be a source for synthetic ingredients, harmful chemicals, and hormones - is causing problems for a lot of people, and that eating healthier will help stop those diseases from occurring.

In my view, this abundance of environmental chemicals is a massively overlooked phenomenon in many aspects of health, including acne.

What you say is correct, the average man's low testosterone is due to the lack of testosterone boosting vitamins and minerals, more secretive testosterone boosting phytonutrients in fruits and vegetables, and additionally, the abundance of environmental chemicals like phthalates in plastic, but if all of their junk food coincidentally consisted of burger king, Big Macs, and greasy fish rather than carbohydrates, the situation could even be worse.

2) The abundance of hormone - disrupting chemicals in personal care items, pesticide - covered foods, and even tap water.

You see, our food contains an abundance of nutrients, natural chemicals, colours, flavours, proteins, sugars and carbohydrates that can affect us all in different ways.

The rapidly accumulating evidence of soil depletion over wide agricultural areas, the reduction in crop yields on improperly fertilized or unfertilized areas and on others, the reduction of fertility levels to the point where fertilizer applications represent the minimum subsistence diet, combined with an aroused public consciousness of the importance of soil fertility conservation and restoration, will inevitably lead to a demand that the chemical industry provide here the same high order of service which it offers elsewhere in meeting man's aspirations for more abundance and greater efficiency.

4 How will the abundance of cheap Natural Gas be used between the competing interests of Big Oil (Export) and Big Chemical (Use internally to make cheap chemicals)?

Unfortunately, the paws happen to have an abundance of the types of cells that are more than happy to release these irritating chemicals into the skin of your dogs paws.

Studies of potential climate change effects (e.g., changes in temperature, circulation, or the abundance of other chemicals) allow for much less ambiguity in accurately attributing any observed changes in the ozone layer to their appropriate cause.