Active upper-atmosphere chemistry and dynamics from polar circulation reversal on Titan.

Abstract:

:Saturn's moon Titan has a nitrogen atmosphere comparable to Earth's, with a surface pressure of 1.4 bar. Numerical models reproduce the tropospheric conditions very well but have trouble explaining the observed middle-atmosphere temperatures, composition and winds. The top of the middle-atmosphere circulation has been thought to lie at an altitude of 450 to 500 kilometres, where there is a layer of haze that appears to be separated from the main haze deck. This 'detached' haze was previously explained as being due to the co-location of peak haze production and the limit of dynamical transport by the circulation's upper branch. Here we report a build-up of trace gases over the south pole approximately two years after observing the 2009 post-equinox circulation reversal, from which we conclude that middle-atmosphere circulation must extend to an altitude of at least 600 kilometres. The primary drivers of this circulation are summer-hemisphere heating of haze by absorption of solar radiation and winter-hemisphere cooling due to infrared emission by haze and trace gases; our results therefore imply that these effects are important well into the thermosphere (altitudes higher than 500 kilometres). This requires both active upper-atmosphere chemistry, consistent with the detection of high-complexity molecules and ions at altitudes greater than 950 kilometres, and an alternative explanation for the detached haze, such as a transition in haze particle growth from monomers to fractal structures.

journal_name

Nature

journal_title

Nature

authors

Teanby NA,Irwin PG,Nixon CA,de Kok R,Vinatier S,Coustenis A,Sefton-Nash E,Calcutt SB,Flasar FM

doi

10.1038/nature11611

subject

Has Abstract

pub_date

2012-11-29 00:00:00

pages

732-5

issue

7426

eissn

0028-0836

issn

1476-4687

pii

nature11611

journal_volume

491

pub_type

杂志文章

相关文献

NATURE文献大全
  • Ben Barres: neuroscience pioneer, gender champion.

    abstract:: ...

    journal_title:Nature

    pub_type: 新闻

    doi:10.1038/d41586-018-07109-2

    authors: Freeman M

    更新日期:2018-10-01 00:00:00

  • Half-metallic graphene nanoribbons.

    abstract::Electrical current can be completely spin polarized in a class of materials known as half-metals, as a result of the coexistence of metallic nature for electrons with one spin orientation and insulating nature for electrons with the other. Such asymmetric electronic states for the different spins have been predicted f...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature05180

    authors: Son YW,Cohen ML,Louie SG

    更新日期:2006-11-16 00:00:00

  • Evidence for only minor contributions from bacteria to sedimentary organic carbon.

    abstract::Because their molecular signatures are often prominent in extracts of sediments, bacteria are thought to be important contributors to petroleum source beds. It has been shown recently, however, that abundances of biomarkers do not always reflect relative contributions to sedimentary organic carbon (Corg). The contrib...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/369224a0

    authors: Hartgers WA,Sinninghe Damste JS,Requejo AG,Allan J,Hayes JM,de Leeuw JW

    更新日期:1994-05-19 00:00:00

  • Recruitment of cytosolic proteins to a secretory granule membrane depends on Ca2+-calmodulin.

    abstract::An increase in free calcium triggers catecholamine secretion from chromaffin cells and calmodulin is strongly implicated as the intracellular Ca2+ receptor. In our recent studies of calmodulin action in the chromaffin cell, micromolar Ca2+ concentrations resulted in calmodulin and cytosolic proteins becoming bound to ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/301432a0

    authors: Geisow MJ,Burgoyne RD

    更新日期:1983-02-03 00:00:00

  • Recognition of a lipid antigen by CD1-restricted alpha beta+ T cells.

    abstract::Major histocompatibility complex (MHC) class I and class II molecules bind immunogenic peptides and present them to lymphocytes bearing the alpha beta T-cell antigen receptor (TCR). An analogous antigen-presenting function also has been proposed for the non-MHC-encoded CD1 molecules, a family of non-polymorphic, beta ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/372691a0

    authors: Beckman EM,Porcelli SA,Morita CT,Behar SM,Furlong ST,Brenner MB

    更新日期:1994-12-15 00:00:00

  • Transient radio bursts from rotating neutron stars.

    abstract::The radio sky is relatively unexplored for transient signals, although the potential of radio-transient searches is high. This was demonstrated recently by the discovery of a previously unknown type of source, varying on timescales of minutes to hours. Here we report a search for radio sources that vary on much shorte...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature04440

    authors: McLaughlin MA,Lyne AG,Lorimer DR,Kramer M,Faulkner AJ,Manchester RN,Cordes JM,Camilo F,Possenti A,Stairs IH,Hobbs G,D'Amico N,Burgay M,O'Brien JT

    更新日期:2006-02-16 00:00:00

  • Author Correction: Anti-tumour immunity controlled through mRNA m6A methylation and YTHDF1 in dendritic cells.

    abstract::In this Letter, a citation to 'Fig. 1e' has been corrected to 'Fig. 1d' in the sentence starting "By contrast, the anti-tumour response…". This has been corrected online. ...

    journal_title:Nature

    pub_type: 已发布勘误

    doi:10.1038/s41586-019-1046-1

    authors: Han D,Liu J,Chen C,Dong L,Liu Y,Chang R,Huang X,Liu Y,Wang J,Dougherty U,Bissonnette MB,Shen B,Weichselbaum RR,Xu MM,He C

    更新日期:2019-04-01 00:00:00

  • Single-molecule analysis of DNA uncoiling by a type II topoisomerase.

    abstract::Type II DNA topoisomerases are ubiquitous ATP-dependent enzymes capable of transporting a DNA through a transient double-strand break in a second DNA segment. This enables them to untangle DNA and relax the interwound supercoils (plectonemes) that arise in twisted DNA. In vivo, they are responsible for untangling repl...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/35009144

    authors: Strick TR,Croquette V,Bensimon D

    更新日期:2000-04-20 00:00:00

  • The TLR4 antagonist Eritoran protects mice from lethal influenza infection.

    abstract::There is a pressing need to develop alternatives to annual influenza vaccines and antiviral agents licensed for mitigating influenza infection. Previous studies reported that acute lung injury caused by chemical or microbial insults is secondary to the generation of host-derived, oxidized phospholipid that potently st...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature12118

    authors: Shirey KA,Lai W,Scott AJ,Lipsky M,Mistry P,Pletneva LM,Karp CL,McAlees J,Gioannini TL,Weiss J,Chen WH,Ernst RK,Rossignol DP,Gusovsky F,Blanco JC,Vogel SN

    更新日期:2013-05-23 00:00:00

  • Computed redox potentials and the design of bioreductive agents.

    abstract::Anti-cancer agents that have been made selective for tumour cells by exploiting the known differences in the availability of oxygen between normal and transformed cells are a promising development in cancer chemotherapy. We have recently suggested a new type of bioreductive activity which would depend on a two-electro...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/334080a0

    authors: Reynolds CA,King PM,Richards WG

    更新日期:1988-07-07 00:00:00

  • Strain effects and phase transitions in photonic resonator crystals.

    abstract::Optical structures with periodic variations of the dielectric constant in one or more directions (photonic crystals) have been employed extensively for studying optical diffraction phenomena. Practical interest in such structures arises from the possibilities they offer for tailoring photon modes, and thereby the char...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/35038026

    authors: Pier H,Kapon E,Moser M

    更新日期:2000-10-19 00:00:00

  • Mice deficient for p53 are developmentally normal but susceptible to spontaneous tumours.

    abstract::Mutations in the p53 tumour-suppressor gene are the most frequently observed genetic lesions in human cancers. To investigate the role of the p53 gene in mammalian development and tumorigenesis, a null mutation was introduced into the gene by homologous recombination in murine embryonic stem cells. Mice homozygous for...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/356215a0

    authors: Donehower LA,Harvey M,Slagle BL,McArthur MJ,Montgomery CA Jr,Butel JS,Bradley A

    更新日期:1992-03-19 00:00:00

  • Single-molecule imaging of transcription dynamics in somatic stem cells.

    abstract::Molecular noise is a natural phenomenon that is inherent to all biological systems1,2. How stochastic processes give rise to the robust outcomes that support tissue homeostasis remains unclear. Here we use single-molecule RNA fluorescent in situ hybridization (smFISH) on mouse stem cells derived from haematopoietic ti...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/s41586-020-2432-4

    authors: Wheat JC,Sella Y,Willcockson M,Skoultchi AI,Bergman A,Singer RH,Steidl U

    更新日期:2020-07-01 00:00:00

  • Stage-specific control of neuronal migration by somatostatin.

    abstract::Developing neurons transiently express somatostatin and its receptors, but little is known about their function at these early stages. As we thought that endogenous somatostatin might control the migratory behaviour of immature neurons, we have examined the effects of somatostatin in cerebellar granule cells of early ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/415077a

    authors: Yacubova E,Komuro H

    更新日期:2002-01-03 00:00:00

  • The Polycomb group protein EZH2 directly controls DNA methylation.

    abstract::The establishment and maintenance of epigenetic gene silencing is fundamental to cell determination and function. The essential epigenetic systems involved in heritable repression of gene activity are the Polycomb group (PcG) proteins and the DNA methylation systems. Here we show that the corresponding silencing pathw...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature04431

    authors: Viré E,Brenner C,Deplus R,Blanchon L,Fraga M,Didelot C,Morey L,Van Eynde A,Bernard D,Vanderwinden JM,Bollen M,Esteller M,Di Croce L,de Launoit Y,Fuks F

    更新日期:2006-02-16 00:00:00

  • Foot strike patterns and collision forces in habitually barefoot versus shod runners.

    abstract::Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels and little cushioning relative to modern running sh...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature08723

    authors: Lieberman DE,Venkadesan M,Werbel WA,Daoud AI,D'Andrea S,Davis IS,Mang'eni RO,Pitsiladis Y

    更新日期:2010-01-28 00:00:00

  • High-harmonic generation by resonant plasmon field enhancement.

    abstract::High-harmonic generation by focusing a femtosecond laser onto a gas is a well-known method of producing coherent extreme-ultraviolet (EUV) light. This nonlinear conversion process requires high pulse intensities, greater than 10(13) W cm(-2), which are not directly attainable using only the output power of a femtoseco...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature07012

    authors: Kim S,Jin J,Kim YJ,Park IY,Kim Y,Kim SW

    更新日期:2008-06-05 00:00:00

  • Complex lipid determines tissue-specific replication of Mycobacterium tuberculosis in mice.

    abstract::Tuberculosis is the leading cause of death in the world resulting from a single bacterial infection. Despite its enormous burden on world health, little is known about the molecular mechanisms of pathogenesis of Mycobacterium tuberculosis. Bacterial multiplication and concomitant tissue damage within an infected host,...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/47042

    authors: Cox JS,Chen B,McNeil M,Jacobs WR Jr

    更新日期:1999-11-04 00:00:00

  • The auroral footprint of Enceladus on Saturn.

    abstract::Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature09928

    authors: Pryor WR,Rymer AM,Mitchell DG,Hill TW,Young DT,Saur J,Jones GH,Jacobsen S,Cowley SW,Mauk BH,Coates AJ,Gustin J,Grodent D,Gérard JC,Lamy L,Nichols JD,Krimigis SM,Esposito LW,Dougherty MK,Jouchoux AJ,Stewart AI,Mc

    更新日期:2011-04-21 00:00:00

  • Retinal astrocytes are immigrants from the optic nerve.

    abstract::The retina in most mammals contains two types of macroglial cells--Müller cells, which span the entire thickness of the retina, and astrocytes, which are mainly confined to the nerve fibre layer. Whereas Müller cells are diffusely distributed in all vertebrate retinae, the presence and distribution of retinal astrocyt...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/332834a0

    authors: Watanabe T,Raff MC

    更新日期:1988-04-28 00:00:00

  • Coral mucus functions as an energy carrier and particle trap in the reef ecosystem.

    abstract::Zooxanthellae, endosymbiotic algae of reef-building corals, substantially contribute to the high gross primary production of coral reefs, but corals exude up to half of the carbon assimilated by their zooxanthellae as mucus. Here we show that released coral mucus efficiently traps organic matter from the water column ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature02344

    authors: Wild C,Huettel M,Klueter A,Kremb SG,Rasheed MY,Jørgensen BB

    更新日期:2004-03-04 00:00:00

  • Distinct relationships of parietal and prefrontal cortices to evidence accumulation.

    abstract::Gradual accumulation of evidence is thought to be fundamental for decision-making, and its neural correlates have been found in several brain regions. Here we develop a generalizable method to measure tuning curves that specify the relationship between neural responses and mentally accumulated evidence, and apply it t...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature14066

    authors: Hanks TD,Kopec CD,Brunton BW,Duan CA,Erlich JC,Brody CD

    更新日期:2015-04-09 00:00:00

  • Identification of the BAL-labile factor.

    abstract::One of us has previously reported that treatment of the Keilin and Hartree heart-muscle preparation with 2,3-dimercaptopropanol (BAL), in the presence of air, leads to the complete inactivation of the succinate oxidase system with little if any effect on the activities of succinate dehydrogenase (until more than half ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/288717a0

    authors: Slater EC,de Vries S

    更新日期:1980-12-25 00:00:00

  • Agonist/endogenous peptide-MHC heterodimers drive T cell activation and sensitivity.

    abstract::Alphabeta T lymphocytes are able to detect even a single peptide-major histocompatibility complex (MHC) on the surface of an antigen-presenting cell. This is despite clear evidence, at least with CD4+ T cells, that monomeric ligands are not stimulatory. In an effort to understand how this remarkable sensitivity is ach...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature03391

    authors: Krogsgaard M,Li QJ,Sumen C,Huppa JB,Huse M,Davis MM

    更新日期:2005-03-10 00:00:00

  • A living display system resolved pixel by pixel.

    abstract:: ...

    journal_title:Nature

    pub_type: 评论,新闻

    doi:10.1038/d41586-018-05909-0

    authors: Jouary A,Machens CK

    更新日期:2018-10-01 00:00:00

  • Structure of mouse metallothionein-I gene and its mRNA.

    abstract::Metallothioneins are small cysteine-rich proteins that bind heavy metals such as zinc, cadmium, copper and mercury. Recent interest in these proteins has focused on the part they play in zinc metabolism and heavy metal detoxification. Our interest in metallothionein genes stems largely from the observations that these...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/292267a0

    authors: Glanville N,Durnam DM,Palmiter RD

    更新日期:1981-07-16 00:00:00

  • How AI and satellites could help predict volcanic eruptions.

    abstract:: ...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/d41586-019-00752-3

    authors: Witze A

    更新日期:2019-03-01 00:00:00

  • Effective global conservation strategies.

    abstract::Using data on the global distribution of mammal, bird and amphibian species, Grenyer et al. conclude that planning based on individual taxa does not provide efficient solutions for the conservation of other taxa. They also report that the performance of existing global conservation strategies-endemic bird areas, biodi...

    journal_title:Nature

    pub_type: 评论,杂志文章

    doi:10.1038/nature06374

    authors: Rodrigues AS

    更新日期:2007-12-06 00:00:00

  • The complete genome of the hyperthermophilic bacterium Aquifex aeolicus.

    abstract::Aquifex aeolicus was one of the earliest diverging, and is one of the most thermophilic, bacteria known. It can grow on hydrogen, oxygen, carbon dioxide, and mineral salts. The complex metabolic machinery needed for A. aeolicus to function as a chemolithoautotroph (an organism which uses an inorganic carbon source for...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/32831

    authors: Deckert G,Warren PV,Gaasterland T,Young WG,Lenox AL,Graham DE,Overbeek R,Snead MA,Keller M,Aujay M,Huber R,Feldman RA,Short JM,Olsen GJ,Swanson RV

    更新日期:1998-03-26 00:00:00

  • Formation of new chromatin domains determines pathogenicity of genomic duplications.

    abstract::Chromosome conformation capture methods have identified subchromosomal structures of higher-order chromatin interactions called topologically associated domains (TADs) that are separated from each other by boundary regions. By subdividing the genome into discrete regulatory units, TADs restrict the contacts that enhan...

    journal_title:Nature

    pub_type: 杂志文章

    doi:10.1038/nature19800

    authors: Franke M,Ibrahim DM,Andrey G,Schwarzer W,Heinrich V,Schöpflin R,Kraft K,Kempfer R,Jerković I,Chan WL,Spielmann M,Timmermann B,Wittler L,Kurth I,Cambiaso P,Zuffardi O,Houge G,Lambie L,Brancati F,Pombo A,Vingron M,

    更新日期:2016-10-13 00:00:00