Dirbe Comet Trails

Abstract

Re-examination of the COBE DIRBE data reveals the thermal emission of several comet dust trails. The dust trails of 1P/Halley, 169P/NEAT, and 3200 Phaethon have not been previously reported. The known trails of 2P/Encke, and 73P/Schwassmann-Wachmann 3 are also seen. The dust trails have 12 and 25 µm surface brightnesses of < 0.1 and < 0.15 MJy sr −1 , respectively, which is < 1% of the zodiacal light intensity. The trails are very difficult to see in any single daily image of the sky, but are evident as rapidly moving linear features in movies of the DIRBE data. Some trails are clearest when crossing through the orbital plane of the parent comet, but others are best seen at high ecliptic latitudes as the Earth passes over or under the dust trail. All these comets have known associations with meteor showers. This re-examination also reveals one additional comet and 13 additional asteroids that had not previously been recognized in the DIRBE data. Subject headings: comets: individual (1P/Halley, 2P/Encke, 73P/Schwassmann-Wachmann 3, 169P/NEAT) -meteorites, meteors, meteoroids -minor planets, asteroids: individual (3200 Phaethon) -zodiacal dust

Parker Solar Probe Observations of a Dust Trail in the Orbit of (3200) Phaethon

“…While not presented in detail here, observations of the same region of space recorded by WISPR during PSP's second encounter (2019 March 30 -April 10) show a visually and photometrically identical dust trail, with Phaethon just three months from perihelion at that time. The implication from these observations is that the orbit is uniformly filled, a result consistent with the COBE DIRBE trail detection (Arendt 2014) which rather coincidentally occurred while Phaethon was near aphelion. Ye et al (2018) argue that the Phaethon orbit fills in ∼250 years, so it is perhaps not surprising that we can confirm this, and the Geminids are known to encompass their entire orbit.…”

“…In 2014, a re-examination of infrared observations from the Diffuse Infrared Background Experiment (DIRBE) on the Cosmic Background Explorer (COBE) revealed a dust trail in the orbit of Phaethon (Arendt 2014). Analyses of these observations were largely qualitative rather than quantitative, but notable results were that the trail was detected far from Phaethon itself and was described to "brighten dramatically" as the Earth passed through Phaethon's orbital plane.…”

2 mm GISMO Observations of the Galactic Center. II. A Nonthermal Filament in the Radio Arc and Compact Sources*

“…The data reduction and mosaicking, done with CRUSH (Kovács 2008), yields an image with 21 ′′ (FWHM) resolution. Arendt et al (2019) describe the characterization of the thermal dust emission in the image via the extrapolation of a modified blackbody spectrum based on 160 -500 µm Herschel PACS and SPIRE observations (Molinari et al 2016). The Herschel data, convolved to 37 ′′ resolution, were initially fit on a pixel-to-pixel basis to determine a mean dust temperature, a spectral index, β, of the dust emissivity, κ ν (λ), and a normalization (proportional to the mass).…”

Near-Earth asteroid (3200) Phaethon: Characterization of its orbit, spin state, and thermophysical parameters

“…Moreover, these small particles are quickly swept away by the solar radiation pressure and can hardly be reconciled with the age of the Geminids. The Geminid stream consists of much larger particles than those estimated from the STEREO data, with sizes from 10 µm to about 4-4.5 cm (Arendt 2014;Yanagisawa et al 2008). Some of them might even survive the passage through the Earth's atmosphere (Madiedo et al 2013) and drop meteorites that have never been collected.…”