Browse Articles

  • Letter |

    The primordial abundance of helium, set minutes after the Big Bang, is typically measured in star-forming regions in local metal-poor galaxies. Here the helium abundance of an intergalactic gas cloud is calculated using the light of a background quasar instead.

    • Ryan J. Cooke
    •  & Michele Fumagalli
  • News & Views |

    The study of the early stages of galaxy cluster formation and their evolutionary path is critical for testing our structure-formation models and cosmological paradigm. Recent observations have pushed the detection of ‘protoclusters’ further back in time.

    • Piero Rosati
  • Letter |

    A giant protocluster of galaxies at redshift z ≈ 5.7 is found within a large overdense region containing at least 41 spectroscopically confirmed Lyα-emitting galaxies. It will collapse into one of the most massive clusters known to date.

    • Linhua Jiang
    • , Jin Wu
    • , Fuyan Bian
    • , Yi-Kuan Chiang
    • , Luis C. Ho
    • , Yue Shen
    • , Zhen-Ya Zheng
    • , John I. Bailey III
    • , Guillermo A. Blanc
    • , Jeffrey D. Crane
    • , Xiaohui Fan
    • , Mario Mateo
    • , Edward W. Olszewski
    • , Grecco A. Oyarzún
    • , Ran Wang
    •  & Xue-Bing Wu
  • Article |

    Small polycyclic aromatic hydrocarbons (PAHs) are thought to be nucleation sites for the growth of Titan’s haze layers. Using laboratory experiments and electronic structure calculations, Zhao et al. show that small PAHs can by synthesized by rapid, barrierless reactions in Titan’s low-temperature environments.

    • Long Zhao
    • , Ralf I. Kaiser
    • , Bo Xu
    • , Utuq Ablikim
    • , Musahid Ahmed
    • , Mikhail M. Evseev
    • , Eugene K. Bashkirov
    • , Valeriy N. Azyazov
    •  & Alexander M. Mebel
  • Letter |

    The IRIS spectrograph observed upward ‘pseudo-shocks’ (shocks exhibiting a discontinuity only in plasma density) over an active region of the Sun. Modelling shows that such pseudo-shocks contribute significantly to coronal heating and mass transport.

    • Abhishek Kumar Srivastava
    • , Krzysztof Murawski
    • , Blażej Kuźma
    • , Dariusz Patryk Wójcik
    • , Teimuraz V. Zaqarashvili
    • , Marco Stangalini
    • , Zdzislaw E. Musielak
    • , John Gerard Doyle
    • , Pradeep Kayshap
    •  & Bhola N. Dwivedi
  • News & Views |

    Observations with a continent-wide array of radio telescopes show that the merger of two neutron stars, which produced gravitational waves, successfully launched a very fast and highly collimated jet.

    • Alexander J. van der Horst
  • News & Views |

    • Marios Karouzos
  • Editorial |

    We celebrate four of the most inspirational role models pushing for diversity among astronomers.

  • Meeting Report |

    Gender equity across the globe is improving thanks to dedicated efforts, policies, monitoring, training and assessment. However, progress is slow and more needs to be done. Numbers don’t tell the whole story, but quantitative surveys are helping to gauge the situation.

    • Francesca Primas
  • Comment |

    The detection of biosignatures on extrasolar planets would allow us to explore the predictability of evolution. What could we learn without directly obtaining a sample of life?

    • Charles S. Cockell
  • News & Views |

    The positions and motions of galaxies are dictated by the laws of gravity. A new technique to measure the anisotropy in the three-dimensional redshift distribution of galaxies seriously challenges attempts to go beyond Einstein’s general theory of relativity.

    • Federico Bianchini
  • Letter |

    Predictions for the clustering of galaxies based on general relativity (GR) and on one of its more compelling variants are contrasted with observations. The former agree impressively well with the data, providing strong confirmation of GR on cosmological scales.

    • Jian-hua He
    • , Luigi Guzzo
    • , Baojiu Li
    •  & Carlton M. Baugh
  • Meeting Report |

    The European Astronomical Society (EAS) awarded its most prestigious prizes during its annual meeting, the European Week of Astronomy and Space Science (EWASS), held in Liverpool from 3 April to 6 April 2018.

    • Georges Meylan
  • Mission Control |

    After 60 years of technological and materials development, in August this year the Parker Solar Probe set off on its journey to skim the atmosphere of the Sun. Mission Scientist Adam Szabo summarizes this ambitious adventure.

    • Adam Szabo
  • Letter |

    The identification and dating of ~30 cryovolcanic domes on Ceres from Dawn data shows that cryovolcanism has been continuous on the dwarf planet at least for the last 2.5 Gyr, but not at rates comparable with standard volcanism on terrestrial planets.

    • Michael M. Sori
    • , Hanna G. Sizemore
    • , Shane Byrne
    • , Ali M. Bramson
    • , Michael T. Bland
    • , Nathaniel T. Stein
    •  & Christopher T. Russell
  • Letter |

    Probing the pre-explosion environments of hydrogen-poor superluminous supernovae is important for understanding how they exploded. Here, Lunnan et al. infer the presence of a fast-moving circumstellar shell around iPTF16eh through the detection of a resonance-line light echo, which indicates the massive progenitor experienced pulsational pair instability shell ejections.

    • R. Lunnan
    • , C. Fransson
    • , P. M. Vreeswijk
    • , S. E. Woosley
    • , G. Leloudas
    • , D. A. Perley
    • , R. M. Quimby
    • , Lin Yan
    • , N. Blagorodnova
    • , B. D. Bue
    • , S. B. Cenko
    • , A. De Cia
    • , D. O. Cook
    • , C. U. Fremling
    • , P. Gatkine
    • , A. Gal-Yam
    • , M. M. Kasliwal
    • , S. R. Kulkarni
    • , F. J. Masci
    • , P. E. Nugent
    • , A. Nyholm
    • , A. Rubin
    • , N. Suzuki
    •  & P. Wozniak
  • Letter |

    The mechanisms that sustain turbulence in a molecular cloud are not well understood. Using magnetohydrodynamic simulations, the effects of stellar winds on a cloud are studied, finding that energy can be efficiently transferred in magnetic waves generated by this stellar ‘feedback’.

    • Stella S. R. Offner
    •  & Yue Liu
  • Letter |

    The Patroclus–Menoetius Jupiter Trojan binary could survive its travel from the Kuiper belt to Jupiter’s orbit only if the giant planets’ migrations happened within ~100 Myr after the birth of the Solar System and not after ~700 Myr, as suggested instead by the Late Heavy Bombardment.

    • David Nesvorný
    • , David Vokrouhlický
    • , William F. Bottke
    •  & Harold F. Levison
  • Article |

    The James Webb Space Telescope may detect and distinguish a young galaxy that hosts a direct-collapse black hole and nearby massive metal-free star formation at redshift 15 with as little as a 20,000-second total exposure time across four filters.

    • Kirk S. S. Barrow
    • , Aycin Aykutalp
    •  & John H. Wise
  • Article |

    The shock breakout (SBO) is the first electromagnetic signature of a supernova (SN) explosion. Förster et al. find that in nearly all type II SNe they survey that the SBO occurs on a timescale of days, indicating that the progenitors were surrounded by thick circumstellar matter when they exploded.

    • F. Förster
    • , T. J. Moriya
    • , J. C. Maureira
    • , J. P. Anderson
    • , S. Blinnikov
    • , F. Bufano
    • , G. Cabrera-Vives
    • , A. Clocchiatti
    • , T. de Jaeger
    • , P. A. Estévez
    • , L. Galbany
    • , S. González-Gaitán
    • , G. Gräfener
    • , M. Hamuy
    • , E. Y. Hsiao
    • , P. Huentelemu
    • , P. Huijse
    • , H. Kuncarayakti
    • , J. Martínez
    • , G. Medina
    • , F. Olivares E.
    • , G. Pignata
    • , A. Razza
    • , I. Reyes
    • , J. San Martín
    • , R. C. Smith
    • , E. Vera
    • , A. K. Vivas
    • , A. de Ugarte Postigo
    • , S.-C. Yoon
    • , C. Ashall
    • , M. Fraser
    • , A. Gal-Yam
    • , E. Kankare
    • , L. Le Guillou
    • , P. A. Mazzali
    • , N. A. Walton
    •  & D. R. Young
  • Mission Control |

    HaloSat, NASA’s first astrophysics-focused CubeSat mission — the size of a small briefcase — will survey the Milky Way’s halo in order to assess its complement of hot baryons, explains Principal Investigator Philip Kaaret.

    • Philip Kaaret
  • Comment |

    The National Astronomical Observatory of Japan has been working to increase public familiarity with astronomy. Here we introduce our outreach activities, including the development of interactive tools that make NAOJ data visible to the public.

    • Kumiko Usuda-Sato
    • , Hiroko Tsuzuki
    •  & Hitoshi Yamaoka
  • Editorial |

    Exoplanetary science is one of the most rapidly developing fields in astronomy and has great near- and medium-term prospects, but various challenges can hinder its growth. The community needs to be prepared to discuss them constructively and openly without spiralling into infighting.

  • Comment |

    Understanding how and why star formation turns off in massive galaxies is a major challenge for studies of galaxy evolution. Many theoretical explanations have been proposed, but a definitive consensus is yet to be reached.

    • Allison Man
    •  & Sirio Belli
  • News & Views |

    The Andromeda galaxy’s stellar halo and disk show signs of an active recent merger history. Recent work suggests that most of the disturbances in Andromeda’s disk and the inner halo may be due to a single merger event.

    • Karoline M. Gilbert
  • Letter |

    Cosmochemical evidence is used to constrain models of Jupiter formation, which unfolds in three distinct phases: a rapid pebble accretion during the first Myr, followed by a slower growth controlled by larger planetesimals, ending in a runaway gas accretion stage.

    • Yann Alibert
    • , Julia Venturini
    • , Ravit Helled
    • , Sareh Ataiee
    • , Remo Burn
    • , Luc Senecal
    • , Willy Benz
    • , Lucio Mayer
    • , Christoph Mordasini
    • , Sascha P. Quanz
    •  & Maria Schönbächler
  • Article |

    A 3D magnetohydrodynamic model forecasted the state of the solar corona during the eclipse that occurred on 21 August 2017, using observations taken ten days before the eclipse as boundary conditions. The agreement between the predicted images and those observed during the eclipse is very good.

    • Zoran Mikić
    • , Cooper Downs
    • , Jon A. Linker
    • , Ronald M. Caplan
    • , Duncan H. Mackay
    • , Lisa A. Upton
    • , Pete Riley
    • , Roberto Lionello
    • , Tibor Török
    • , Viacheslav S. Titov
    • , Janvier Wijaya
    • , Miloslav Druckmüller
    • , Jay M. Pasachoff
    •  & Wendy Carlos
  • Letter |

    A data-driven study of the too-big-to-fail problem of Milky Way dwarf spheroidals within the self-interacting dark matter paradigm finds a good description of their stellar kinematics and compatibility with the concentration–mass relation of pure cold dark matter simulations.

    • Mauro Valli
    •  & Hai-Bo Yu
  • Letter |

    Star TYC 429-2097-1 contains the most lithium of any giant star, but lithium is too fragile to survive in the deep layers of a stellar atmosphere. How does the enrichment arise? Yan et al. rule out external sources (engulfment, accretion), favouring an internal process called ‘extra mixing’.

    • Hong-Liang Yan
    • , Jian-Rong Shi
    • , Yu-Tao Zhou
    • , Yong-Shou Chen
    • , Er-Tao Li
    • , Suyalatu Zhang
    • , Shao-Lan Bi
    • , Ya-Qian Wu
    • , Zhi-Hong Li
    • , Bing Guo
    • , Wei-Ping Liu
    • , Qi Gao
    • , Jun-Bo Zhang
    • , Ze-Ming Zhou
    • , Hai-Ning Li
    •  & Gang Zhao
  • Article |

    An image-template analysis of eight years of Fermi-LAT data shows that the anomalous emission of gigaelectronvolt energies close to the centre of our Galaxy is better fitted with a boxy-shaped bulge generated by stars — possibly millisecond pulsars — than with a dark matter signal.

    • Richard Bartels
    • , Emma Storm
    • , Christoph Weniger
    •  & Francesca Calore
  • Letter |

    Double-shell planetary nebula HuBi 1 has an inner shell that emits in low ionization potential species, and an outer shell that emits in high-ionization species. This is the inverse of the usual case. The cause is the nebula’s rapidly fading central star that went through a ‘born-again’ event.

    • Martín A. Guerrero
    • , Xuan Fang
    • , Marcelo M. Miller Bertolami
    • , Gerardo Ramos-Larios
    • , Helge Todt
    • , Alexandre Alarie
    • , Laurence Sabin
    • , Luis F. Miranda
    • , Christophe Morisset
    • , Carolina Kehrig
    •  & Saúl A. Zavala
  • Editorial |

    The 2020 US Decadal Survey for Astrophysics is almost here — but in these years of flat cash and major mission delays, how much can we afford to dream?

  • News & Views |

    Dark matter is deemed essential for describing galaxy dynamics. A prominent alternative theory can make the same predictions without dark matter, by introducing a universal acceleration constant. Recent high-quality observations of galaxies are used to investigate whether this constant is really a constant.

    • W. J. G. de Blok
  • Comment |

    The next-generation observatory Lynx will provide an unprecedented X-ray view of the otherwise invisible Universe, directly observing the dawn of supermassive black holes, revealing the drivers of galaxy formation, tracing stellar activity including effects on planet habitability, and transforming our knowledge of the endpoints of stellar evolution.

    • Feryal Özel