author={David C. Jewitt and Jing Li and Jessica Agarwal},
  journal={The Astrophysical Journal Letters},
We report the discovery of a comet-like tail on asteroid (3200) Phaethon when imaged at optical wavelengths near perihelion. In both 2009 and 2012, the tail appears ≳350″ (2.5 × 108 m) in length and extends approximately in the projected anti-solar direction. We interpret the tail as being caused by dust particles accelerated by solar radiation pressure. The sudden appearance and the morphology of the tail indicate that the dust particles are small, with an effective radius ∼1 μm and a combined… 
High-resolution Thermal Infrared Imaging of 3200 Phaethon
We present thermal infrared observations of the active asteroid (and Geminid meteoroid stream parent) 3200 Phaethon using the Very Large Telescope. The images, at 10.7 μm wavelength, were taken with
Extremely strong polarization of an active asteroid (3200) Phaethon
Polarimetric observation of Phaethon over a wide range of solar phase angle and it is revealed that the asteroid exhibits a very strong linear polarization, implying that Phoethon’s geometric albedo is lower than the current estimate obtained through radiometric observation.
Thermal decomposition as an activity driver of near-Earth asteroid (3200) Phaethon
Purpose: Near-Earth asteroid (3200) Phaethon is an active asteroid with a dust tail repeatedly observed over the past decade for ∼ 3 days during each perihelion passage down to a heliocentric
Near-infrared observations of active asteroid (3200) Phaethon reveal no evidence for hydration
It is shown that the northern hemisphere and the equatorial region of this asteroid reveal no evidence of hydration in the near-infrared spectra, suggesting that Phaethon’s modern activity is not due to volatile sublimation or devolatilization of phyllosilicates on its surface.
In Search of Recent Disruption of (3200) Phaethon: Model Implication and Hubble Space Telescope Search
Near-Earth asteroid (3200) Phaethon is notable for its association with a strong annual meteor shower, the Geminids, indicative of one or more episodes of mass ejection in the past. The mechanism of
Some asteroids eject dust, unexpectedly producing transient, comet-like comae and tails. First ascribed to the sublimation of near-surface water ice, mass-losing asteroids (also called “main-belt
Parker Solar Probe Observations of a Dust Trail in the Orbit of (3200) Phaethon
We present the identification and preliminary analysis of a dust trail following the orbit of (3200) Phaethon as seen in white-light images recorded by the Wide-field Imager for Parker Solar Probe
Rotational Mass Shedding from Asteroid (6478) Gault
The ∼4 km diameter main belt asteroid 6478 Gault has ejected dust intermittently since at least 2013. The character of the emission, including its episodic nature and the low speed of the ejected


Activity in Geminid Parent (3200) Phaethon
The asteroid (3200) Phaethon is widely recognized as the parent of the Geminid meteoroid stream. However, it has never shown evidence for ongoing mass loss or for any form of comet-like activity that
We present a study of planet-crossing asteroid (3200) Phaethon at three successive perihelia in 2009, 2010, and 2012, using the NASA STEREO spacecraft. Phaethon is clearly detected in 2009 and 2012,
An upper limit on gas production from 3200 Phaethon
The Active Asteroids
Some asteroids eject dust, unexpectedly producing transient, comet-like comae and tails. First ascribed to the sublimation of near-surface water ice, mass-losing asteroids (also called “main-belt
Solar-Radiation Heating Effects on 3200 Phaethon
Apollo-type near-Earth asteroid 3200 Phaethon, having a small perihelion distance of q � 0.14 AU, is classified as F- or B-type, one of subclasses among the C-complex (C-, G-, B-, and F-types)
Thermal Evolution of the Phaethon–Geminid Stream Complex
The thermal evolution of the Geminid meteor stream and the Phaethon–Geminid stream Complex (PGC) are summarized. Sodium contents of Geminid meteor streams are altered thermally, perhaps during
Search for Activity in 3200 Phaethon
We present deep optical imaging of Geminid meteor stream parent 3200 Phaethon taken in search of low-level cometary activity (i.e., coma or dust trail). Although no unambiguous cometary behavior was
4015 Wilson-Harrington, 2201 Oljato, and 3200 Phaethon: Search for CN Emission
Abstract There is evidence that 2201 Oljato and 3200 Phaethon may be inactive cometary remnants. Comet P/Wilson-Harrington (1949 III) was discovered to be the same object as asteroid 4015 1979 VA.
Mostly Dormant Comets and their Disintegration into Meteoroid Streams: A Review
The history of associating meteor showers with asteroidal-looking objects is long, dating to before the 1983 discovery that 3200 Phaethon moves among the Geminids. Only since the more recent
Mathematical modelling of the Geminid meteoroid stream
The Geminid meteoroid stream formation and evolution were studied by the method of nested polynomials. The stream has two layers formed due to differences in orbital parameters of particles ejected