Zodiacal light
Parts of this article (those related to the hypothesized origin of the zodiacal cloud - Mars dust, rather than comets or asteroids) need to be updated.(March 2021) |
Zodiacal light is a faint glow of
Zodiacal light contributes[7] to the natural light of the sky, though since zodiacal light is very faint, it is often outshined and rendered invisible by moonlight or light pollution.
The interplanetary dust in the
The Pioneer 10 and Helios spacecraft observations in the 1970s revealed zodiacal light to be scattered by the interplanetary dust cloud in the Solar System.[10][11] Analysis of images of impact debris from the
Viewing
In the mid-latitudes, the zodiacal light is best observed in the western sky in the spring after the evening twilight has completely disappeared, or in the eastern sky in the autumn just before the morning twilight appears. The zodiacal light appears as a column, brighter at the horizon and tilted at the angle of the ecliptic. The light scattered from extremely small dust particles is strongly
The dust further from the ecliptic is almost undetectable except when viewed at a small angle with the Sun. Thus it is possible to see more of the width at small angles toward the Sun, and it appears wider near the horizon, closer to the Sun under the horizon.
Origin
The source of the dust has been long debated. Until recently, it was thought that the dust originated from the tails of active comets and from collisions between asteroids in the asteroid belt.[17] Many of our meteor showers have no known active comet parent bodies. Over 85 percent of the dust is attributed to occasional fragmentations of Jupiter-family comets that are nearly dormant.[18] Jupiter-family comets have orbital periods of less than 20 years[19] and are considered dormant when not actively outgassing, but may do so in the future.[20] The first fully dynamical model of the zodiacal cloud demonstrated that only if the dust was released in orbits that approach Jupiter, is it stirred up enough to explain the thickness of the zodiacal dust cloud. The dust in meteoroid streams is much larger, 300 to 10,000 micrometres in diameter, and falls apart into smaller zodiacal dust grains over time.
The Poynting–Robertson effect forces the dust into more circular (but still elongated) orbits, while spiralling slowly into the Sun. Hence a continuous source of new particles is needed to maintain the zodiacal cloud. Cometary dust and dust generated by collisions among the asteroids are believed to be mostly responsible for the maintenance of the dust cloud producing the zodiacal light and the gegenschein.
Particles can be reduced in size by collisions or by space weathering. When ground down to sizes less than 10 micrometres, the grains are removed from the inner Solar System by solar radiation pressure. The dust is then replenished by the infall from comets. Zodiacal dust around nearby stars is called
In 2015, new results from the secondary ion dust spectrometer COSIMA on board the ESA/Rosetta orbiter confirmed that the parent bodies of interplanetary dust are most probably Jupiter-family comets such as comet 67P/Churyumov–Gerasimenko.[22] Data from the Juno mission indicate that the dust close to Earth has a local origin in the inner Solar System, best fitting the planet Mars as a source.[23]
Appearance
Zodiacal light is produced by sunlight reflecting off dust particles in the Solar System known as cosmic dust. Consequently, its spectrum is the same as the solar spectrum. The material producing the zodiacal light is located in a lens-shaped volume of space centered on the sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the Solar System, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is quite small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as the Moon, each particle would be 8 km from its neighbors. The gegenschein may be caused by particles directly opposite the Sun as seen from Earth, which would be in full phase.
According to Nesvorný and Jenniskens, when the dust grains are as small as about 150 micrometres in size, they will hit the Earth at an average speed of 14.5 km/s, many as slowly as 12 km/s. If so, they pointed out, this
Cultural significance
According to
Importance to Islam
The
Brian May
In 2007, Brian May, lead guitarist with the band Queen, completed his thesis, A Survey of Radial Velocities in the Zodiacal Dust Cloud, thirty-six years after abandoning it to pursue a career in music.[30] He was able to submit it only because of the minimal amount of research on the topic undertaken during the intervening years. May described the subject as being one that became "trendy" again in the 2000s.[31]
Other planets
Other planets, like Venus or Mercury,[32] have shown to have rings of interplanetary dust in their orbital spaces.
See also
References
- ^ "False Dawn". www.eso.org. Retrieved 14 February 2017.
- ^ Darling, David. "Zodiacal cloud". Internet Encyclopedia of Science.
- ^ "APOD: 2012 January 16 - Zodiacal Light and the False Dawn".
- ^ "What are Zodiacal Lights?".
- ^ "EarthSky | Zodiacal light: All you need to know". 6 September 2021.
- ^ Coffey, Rebecca. "In Early March, Look To The West For The Zodiacal Light!". Forbes. Retrieved 2021-06-05.
- Bibcode:1997ASPC..124...33R.
- ISBN 978-0-306-46689-2.
- Bibcode:1967SCoA...11..213M.
- ^ ISBN 978-3-540-07615-5.
- Bibcode:1983A&A...118..345L. Retrieved 28 July 2022.
- ^ Shekhtman, Lonnie (9 March 2021). "Serendipitous Juno Detections Shatter Ideas About Origin of Zodiacal Light". Jet Propulsion Laboratory. NASA. Archived from the original on 18 March 2021. Retrieved 19 March 2021.
- . Retrieved 28 July 2022.
- .
- S2CID 199117335. Retrieved 24 January 2022.
- ^ "Moonlight and Zodiacal Light Over La Silla". ESO Picture of the Week. Retrieved 21 July 2013.
- Bibcode:2006DPS....38.4101E.
- S2CID 18865066.
- ISBN 978-0-521-85349-1.
- ^ SPACE.com Staff (6 January 2011). "Comet or Asteroid? Big Space Rock Has Identity Crisis". SPACE.com. Retrieved 23 May 2011.
Dormant comets retain some subsurface volatiles and may start outgassing once again as they near the sun.
- ^ "Romantic Sunset over the VLT". www.eso.org. European Southern Observatory. Retrieved 21 April 2015.
- S2CID 205242328.
- ^ Space Daily: Juno data shatter ideas about origin of Zodiacal Light
- ^ a b Ley, Willy (April 1961). "The Puzzle Called Gegenschein". For Your Information. Galaxy Science Fiction. pp. 74–84.
- ISBN 978-0-521-85349-1.
- ISBN 978-3-642-62647-0. Retrieved 23 March 2022.
- ISBN 978-1-107-03361-0.
- ^ Sahih Muslim 1094c – The Book of Fasting – Sunnah.com – Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم)
- ^ "Sahih Moslim (The Authentic Hadiths of Muslim) 1-4 Vol 2: صحيح مسلم 1/4 [عربي/إنكليزي] ج2". January 2011.
- ISBN 978-0-387-77705-4. Retrieved 27 May 2017.
- ^ Terri Gross interviews Brian May, National Public Radio show Fresh Air
- ^ Frazier, Sarah (2021-04-16). "NASA's Parker Solar Probe Sees Venus Orbital Dust Ring". NASA. Retrieved 2023-01-21.
External links
- Reach, W. T. (1997). "The structured zodiacal light: IRAS, COBE, and ISO observations". Diffuse Infrared Radiation and the IRTS. ASP Conference Series. 124, 33–40
- "Zodiacal Light and the Gegenschein", an essay by J. E. Littleton Archived 2006-02-26 at the Wayback Machine
- Zodiacal Light and the False Dawn September 25, 2007
- Zodiacal Light Over Laguna Verde October 29, 2009
- Zodiacal light as seen from above the Himalayan Hills in Uttarakhand, India