A Short-duration Event as the Cause of Dust Ejection from Main-Belt Comet P/2012 F5 (Gibbs).

Panels (a) and (b) correspond to the observation and best-fitted image for the observation on 2012 May 18. Panel (c) shows observed and modeled scans along the trail of those images. Panels (d), (e), and (f) give the same as (a), (b), and (c), respectivel
Panels (a) and (b) correspond to the observation and best-fitted image for the observation on 2012 May 18. Panel (c) shows observed and modeled scans along the trail of those images. Panels (d), (e), and (f) give the same as (a), (b), and (c), respectivel
Advertised on
References
ApJ 761, 12M, 2012

We present observations and an interpretative model of the dust environment of the Main-Belt Comet P/2010 F5 (Gibbs). The narrow dust trails observed can be interpreted unequivocally as an impulsive event that took place around 2011 July 1 with an uncertainty of ±10 days, and a duration of less than a day, possibly of the order of a few hours. The best Monte Carlo dust model fits to the observed trail brightness imply ejection velocities in the range 8-10 cm s–1 for particle sizes between 30 cm and 130 μm. This weak dependence of velocity on size contrasts with that expected from ice sublimation and agrees with that found recently for (596) Scheila, a likely impacted asteroid. The particles seen in the trail are found to follow a power-law size distribution of index ≈  –3.7. Assuming that the slowest particles were ejected at the escape velocity of the nucleus, its size is constrained to about 200-300 m in diameter. The total ejected dust mass is > ~ 5 × 108 kg, which represents approximately 4%-20% of the nucleus mass.

News type
Research news

It may interest you

  • alpha_plot_density_gamma_b
    Research news
    The universal variability of the stellar initial mass function probed by the TIMER survey
    The universality of the stellar initial mass function (IMF) is one of the most widespread assumptions in modern Astronomy and yet, it might be flawed. While observations in the Milky Way generally support an IMF that is invariant with respect to the local conditions under which stars form, measurements of massive early-type galaxies systematically point towards a non-universal IMF. To bridge the gap between both sets of evidence, in this work we measured for the first time the low-mass end of the IMF from the integrated spectra of a Milky Way-like galaxy, NGC3351. We found that the slope of
    Advertised on
  • Action space (normalized to the sum of the three actions of motion, Jtot) of Gaia RVS stars
    Research news
    The Metal-Poor Edge of the Milky Way’s Thin Disk
    The formation and evolution of the disk of our Galaxy, the Milky Way, remains an enigma in astronomy. In particular, the relationship between the thick disk and the thin disk —two key components of the Milky Way— is still unclear. Understanding the chemical and dynamical properties of the stars within these disks is crucial, especially in the parameter spaces where their characteristics overlap, such the metallicity regime around [Fe/H] ~ -0.7, which marks the metal-poor end of the thin disk, higher than that of the thick disk. This is often interpreted as an indication that the thin disk
    Advertised on
  • RSOph_MWL_TransientsUniverse
    Research news
    A Very-High-Energy Gamma-Ray View of the Transient Sky
    The development of the latest generation of Imaging Atmospheric Cherenkov Telescopes (IACTs) over recent decades has led to the discovery of new extreme astrophysical phenomena in the very-high-energy (VHE, E > 100 GeV) gamma-ray regime. Time-domain and multi-messenger astronomy are inevitably connected to the physics of transient VHE emitters, which show unexpected (and mostly unpredictable) flaring or exploding episodes at different timescales. These transients often share the physical processes responsible for the production of the gamma-ray emission, through cosmic-ray acceleration
    Advertised on