Mr Venkataraman did briefly a fact of jargons , many may not be aware of ; I liked it; so expanded it with some modifications for general people to understand the astronomy Thank u all and Mr V
I During a solar eclipse, which occurs on a new moon day, the alignment of the Sun, Moon, and Earth is crucial. Here's a brief explanation of their declinations during this event: 1. Sun: The Sun's declination refers to its position north or south of the celestial equator. During a solar eclipse, the Sun's declination varies depending on the time of year and the specific location on Earth where the eclipse is observed. At the moment of a solar eclipse, the Sun's declination will typically be near the ecliptic, the apparent path of the Sun in the sky. 2. Moon: The Moon's declination also varies throughout its orbit around the Earth. During a solar eclipse, the Moon's declination will align closely with the Sun's declination, as the Moon passes between the Sun and the Earth. This alignment is what allows the Moon to cast its shadow on the Earth, causing the solar eclipse. 3. Earth: The Earth's declination remains relatively constant during a solar eclipse. However, its axial tilt (approximately 23.5 degrees) plays a significant role in the occurrence of solar eclipses, as it determines the inclination of the Earth's orbit relative to the Sun's path. Overall, during a solar eclipse on a new moon day, the Sun, Moon, and Earth are aligned in such a way that the Moon blocks the Sun's light from reaching certain areas on the Earth's surface, creating the phenomenon of a solar eclipse. II The term "polar distance" typically refers to the angular distance of a celestial object from the celestial pole. It is measured along the celestial meridian, which is a great circle passing through the celestial poles and the zenith of a specific location on Earth. For example, if we consider the North Celestial Pole, the polar distance of a celestial object is the angular distance from that object to the North Celestial Pole along the celestial meridian. Similarly, for the South Celestial Pole, the polar distance of a celestial object is the angular distance from that object to the South Celestial Pole along the celestial meridian. The polar distance is complementary to the declination. While declination measures how far a celestial object is north or south of the celestial equator, the polar distance measures how far it is from the celestial pole. In the context of a solar eclipse, the Sun's polar distance would be its angular distance from the celestial pole at the time of the eclipse. This value would depend on factors such as the observer's location on Earth and the specific time of the eclipse.Top of Form III Yes, sunlight is visible beyond the poles of the Earth. During the polar summer, when the Sun does not set for several months, sunlight is indeed visible beyond the poles. In the northern hemisphere, this phenomenon occurs in regions like northern Alaska, Canada, Scandinavia, and parts of Russia during their respective summers. In the southern hemisphere, it occurs in places like Antarctica during its summer. Due to the tilt of the Earth's axis, during the summer solstice, the Sun remains above the horizon at high latitudes near the poles for extended periods, sometimes even for 24 hours a day. This phenomenon is known as the midnight sun. Conversely, during polar winter, the Sun does not rise above the horizon for several months, leading to the polar night. IV "Polar distance" is not a standalone unit of measurement like degrees or meters. It's a concept used in astronomy to describe the angular distance of a celestial object from one of the celestial poles along the celestial meridian. However, if you're referring to an angle of 70 degrees from one of the celestial poles, that would represent a significant distance away from the pole along the celestial meridian. For example, if you're talking about the North Celestial Pole, an object with a polar distance of 70 degrees would be quite far from the pole toward the celestial equator. In simple terms, a polar distance of 70 degrees means the object is positioned 70 degrees away from the celestial pole along the celestial meridian. The celestial meridian is an imaginary line that runs from the north celestial pole, through the zenith (the point directly overhead an observer), to the south celestial pole. It is essentially the north-south line in the celestial sphere that corresponds to the meridian line in terrestrial geography. V When we talk about the celestial meridian in relation to a specific location on Earth, we're referring to the great circle passing through the celestial poles and the zenith of that location. It serves as a reference line for measuring the positions of celestial objects in the sky, much like the terrestrial meridian serves as a reference for locations on Earth's surface. Objects' positions are described in terms of their angular distance east or west of the celestial meridian, known as their hour angle. The celestial meridian also plays a role in determining when celestial objects transit, which is when they cross the observer's meridian and are at their highest point in the sky. VI The Earth's tilt of approximately 23.5 degrees refers to the angle between the Earth's rotational axis and its orbital plane around the Sun. This tilt is also known as the axial tilt or obliquity of the Earth. Here's what it means: Axial tilt: The Earth's axis of rotation is an imaginary line around which the Earth rotates. This axis is tilted at an angle of about 23.5 degrees relative to the perpendicular to the plane of its orbit around the Sun. Seasons: The Earth's tilt is responsible for the changing seasons as different parts of the Earth receive varying amounts of sunlight throughout the year. When a hemisphere is tilted towards the Sun, it experiences summer, while the hemisphere tilted away experiences winter. The equinoxes occur when the tilt is perpendicular to the Sun, resulting in equal day and night lengths. Polar day and night: Due to the Earth's tilt, regions near the poles experience periods of continuous daylight (polar day) and continuous darkness (polar night) during their respective summers and winters. Overall, the Earth's tilt of 23.5 degrees plays a crucial role in shaping the planet's climate, weather patterns, and the distribution of sunlight across its surface throughout the year. K RAJARAM IRS 8424 On Mon, 8 Apr 2024 at 20:47, venkat raman <[email protected]> wrote: > Namaste> Solar Eclipse occurs on a Newmoon day but on all days of > Newmoon it does not occur. The Declination of both the Sun and the Moon > must be the same and equal. Declination [ ayanam] is the angular distance > of the heavenly body North or South of the celestial Equator. The > declination of the Sun reaches 23.5 degs North/ South. On the days of > equinox it is zero. The heavenly body does not rise in a place where the > latitude is greater than the polar distance. It is the reason the Poles > experience day/night for six months. When the Declination of the Sun is 20 > degrees North, it will not set in places where the latitude is greater than > 70 degrees. Poles 90 degrees latitude. 90 - 20 = 70, the polar distance. It > will not rise in places where the latitude is greater than 70 degs South. > Lunar Eclipse occurs on a Fullmoon day. The declination of the Sun and the > Moon must be equal and opposite. ie. if the declination of the Sun is > North, the Moon's must be South. A lunar eclipse occurs a fortnight > before/after a Solar Eclipse. On 25th March 2024 on the day of Panguni > Utram a Lunar Eclipse occurred. > > Venkataraman > > -- > On Facebook, please join https://www.facebook.com/groups/keralaiyerstrust > > We are now on Telegram Mobile App also, please join > > Pattars/Kerala Iyers Discussions: https://t.me/PattarsGroup > > Kerala Iyers Trust Decisions only posts : https://t.me/KeralaIyersTrust > > Kerala Iyers Trust Group for Discussions: > https://t.me/KeralaIyersTrustGroup > --- > You received this message because you are subscribed to the Google Groups > "KeralaIyers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/keralaiyers/CAEafiZ07EtR0fjzRpoQYGH6_e%2BH43yWSntHZctN0RmnTFn7Kug%40mail.gmail.com > <https://groups.google.com/d/msgid/keralaiyers/CAEafiZ07EtR0fjzRpoQYGH6_e%2BH43yWSntHZctN0RmnTFn7Kug%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Thatha_Patty" group. 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