Detection of H+3 in interstellar space

  title={Detection of H+3 in interstellar space},
  author={Thomas R. Geballe and Takeshi Oka},
THE H+3 ion is widely believed to play an important role in interstellar chemistry, by initiating the chains of reactions that lead to the production of many of the complex molecular species observed in the interstellar medium1–5. The presence of H+3 in the interstellar medium was first suggested6 in 1961, and its infrared spectrum was measured7 in the laboratory in 1980. But attempts8–11 to detect it in interstellar space have hitherto proved unsuccessful. Here we report the detection of H+3… 

The abundance and excitation of interstellar H3+

  • J. Black
  • Physics
    Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2000
The observed populations of the lowest rotational levels of H2 and H3+ confirm that reactive collisions tend to thermalize the ortho– and para–nuclear–spin species in interstellar clouds.

Detection of H3+ in the diffuse interstellar medium toward Cygnus OB2 No. 12.

This and other work demonstrate the ubiquity of H3+ and its potential as a probe of the physical and chemical conditions in the interstellar medium.

H+3 between the stars

  • T. Geballe
  • Physics
    Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2000
With the recent detection of H3+ in interstellar space, astronomers finally have direct confirmation of H 3+ as the foundation of ion–molecule interstellar chemistry.

Experimental study of recombination of H3+ ions with electrons relevant for interstellar and planetary plasmas

The H3+ is a key ion in the interstellar chemistry. The rate of recombination of H3+ with electrons, ?, plays a pivotal role in the level of ionization of interstellar plasmas. Over the past 50 years

Detection of H3+ in the Diffuse Interstellar Medium: The Galactic Center and Cygnus OB2 Number 12

Absorption lines of H3+ have been detected in the spectra of two infrared sources in the Galactic center and also toward the heavily reddened star Cygnus OB2 No. 12, whose line of sight is believed

Interstellar H3+ Line Absorption toward LkHα 101

We present a detection of three lines of the H ion in the near-infrared spectrum of the Herbig Be star LkHα 101. H is the principal initiator of gas-phase chemistry in interstellar clouds and can be

Interstellar Hydrides

Interstellar hydrides – that is, molecules containing a single heavy element atom with one or more hydrogen atoms – were among the first molecules detected outside the solar system. They lie at the

H3+ recombination and bistability in the interstellar medium

  • G. P. des ForêtsÈ. Roueff
  • Physics
    Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2000
H3+ has recently been detected using infrared absorption towards several dense clouds. We have already shown that models of interstellar chemistry can exhibit several stable steady states, due to the


Recent observations of H2 and H+3 in diffuse interstellar sightlines revealed a difference in the nuclear spin excitation temperatures of the two species. This discrepancy comes as a surprise, as H+3

Using deuterated H3+ and other molecular species to understand the formation of stars and planets

The H + ion plays a key role in the chemistry of dense interstellar gas clouds where stars and planets are forming. The low temperatures and high extinctions of such clouds make direct observations



Identification of features due to H3 + in the infrared spectrum of supernova 1987A

THE molecular ion H3 + occupies a central position in theoretical models of interstellar chemistry1,2. It forms readily in hydrogen-rich interstellar gas clouds when ionized H2 reacts with neutral

Molecular Evolution in Interstellar Clouds. I : Ion Chemistry in Dense Clouds

Molecular abundances are calculated time-dependently using a chemical scheme which is constructed to represent the evolutional feature of all molecules containing up to 2 heavy atoms (C, N, 0, S and

Ultraviolet studies of the interstellar gas

Sounding-rocket and satellite UV observations of interstellar gas clouds are reviewed with major attention given to Copernicus observations of interstellar absorption lines. Analysis of typical

Detection of H3+ on Jupiter

SINCE their detection in the high latitudes of Jupiter, first by the Voyager Ultraviolet Spectrometer (UVS) experiment1,2, then by the International Ultraviolet Explorer (IDE) satellite3, the auroral

A search for interstellar H+3

  • T. Oka
  • Physics
    Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
  • 1981
Based on the results of recent laboratory observation of the infrared v2 fundamental band of the H3 molecular ion, the possibility of observing this important ion in interstellar space is discussed.

Detection of H3(+) from Uranus

The detection of H3(+) in Uranus is reported. Using the CGS4 spectrometer on the UKIRT telescope, we clearly detected 11 emission features of the H3(+) fundamental vibration-rotation band between

Interstellar absorption lines toward NGC 2264 and AFGL 2591 - Abundances of H2, H3(+), and CO

Interstellar absorption-line spectroscopy of NGC 2264 is reported which shows that the CO molecule has a column density of 5 x 10 to the 18th/sq cm and a rotational excitation temperature of 28 K. A

Detection of H3(+) infrared emission lines in Saturn

Three emission lines of the ν 2 fundamental vibration-rotation band of H 3 + have been detected in the ionosphere of Saturn near and at its poles. The peak observed column density of H 3 + (at the

An infrared spectroscopic search for the molecular ion H3(

The molecular ion H3(+) is thought to play a fundamental role in the chemistry of the interstellar medium. Here, a search for infrared vibration-rotation lines of H3(+) at 4 microns toward five

Fractional abundances of molecules in dense interstellar clouds: A compendium of recent model results.

In this paper we present calculated fractional abundances in dense interstellar clouds for selected atomic and molecular species using three different homogeneous, pseudo-time-dependent models