by Ann » Sat Jun 06, 2020 9:08 am
I like the APOD, and I was glad to see galaxy NGC 3077 included in
the M81-M82-NGC 3077 trio.
NGC 3077 is seen here in saturated colors in an image by Sydney.
Fascinatingly, Comet PanSTARRS seems to pay regular visits to the Earth, and grow an anti-tail around May 23 perhaps every seventh year. That is, it seems to grow a tail that seems to point in the wrong direction, opposite the direction of its other tail(s).
This is, however, an optical illusion.
Wikipedia wrote:
The antitail is formed of larger dust particles, which are less affected by the Sun's radiation pressure and tend to remain roughly in the comet's orbital plane and eventually form a disc along the comet's orbit due to the ejection speed of the particles from the comet's surface. As Earth passes through the comet's orbital plane, this disc is seen side on, and appears as the characteristic spike.
So does the antitail and its disc along the comet's orbit have anything to do with meteor showers like the
Leonids? Because this antitail leaves a "disc" of larger particles behind that the Earth might pass through at regular intervals, and as some of these larger particles slam into the Earth's atmosphere, they produce lots of meteors?
Ann
[float=right][img3="Comet PanSTARRs, photographed on May 23, 2013. The long anti-tail is seen at right, the tail is seen at left. Image Credit & Copyright: Joseph Brimacombe."]https://apod.nasa.gov/apod/image/1305/panstarrsSpikeBrimacombe600lum.jpg[/img3][/float] [float=left][img3="Comet PanSTARRs and the Galaxies, photographed on May 22/23, 2020. Image Credit & Copyright: Dan Bartlett."]https://apod.nasa.gov/apod/image/2006/C2017T2_M81M82_May22_23_2020_DEBartlett1024.jpg[/img3][/float]
I like the APOD, and I was glad to see galaxy NGC 3077 included in [url=https://www.researchgate.net/profile/John_Cannon3/publication/231079790/figure/fig1/AS:300501049593863@1448656441651/A-high-resolution-H-I-image-of-the-M81-Group-Yun-et-al-1994-with-the-locations-of.png]the M81-M82-NGC 3077 trio[/url]. [url=https://cdn.astrobin.com/thumbs/OlNXQZAqFVlg_1824x0_dQNmgIYM.jpg]NGC 3077 is seen here[/url] in saturated colors in an image by Sydney.
[float=right][img3="A comet may appear to exhibit a short tail pointing in the opposite direction to its type II or dust tail as viewed from Earth, an anti-tail. Illustration: Io Herodotus."]https://upload.wikimedia.org/wikipedia/commons/c/c3/Anti-tail.jpg[/img3][/float]
Fascinatingly, Comet PanSTARRS seems to pay regular visits to the Earth, and grow an anti-tail around May 23 perhaps every seventh year. That is, it seems to grow a tail that seems to point in the wrong direction, opposite the direction of its other tail(s).
This is, however, an optical illusion.
[quote][url=https://en.wikipedia.org/wiki/Antitail]Wikipedia[/url] wrote:
The antitail is formed of larger dust particles, which are less affected by the Sun's radiation pressure and tend to remain roughly in the comet's orbital plane and eventually form a disc along the comet's orbit due to the ejection speed of the particles from the comet's surface. As Earth passes through the comet's orbital plane, this disc is seen side on, and appears as the characteristic spike.[/quote]
[float=left][img3="This image is a composition of 33 Leonids captured overnight from Nov. 18 to 19, 2001.
(Image: © Koen Miskotte)"]https://cdn.mos.cms.futurecdn.net/GmXNP4UBwfHYuXp73aqfkU-970-80.jpg[/img3][/float]
So does the antitail and its disc along the comet's orbit have anything to do with meteor showers like the [url=https://en.wikipedia.org/wiki/Leonids]Leonids[/url]? Because this antitail leaves a "disc" of larger particles behind that the Earth might pass through at regular intervals, and as some of these larger particles slam into the Earth's atmosphere, they produce lots of meteors?
Ann