Showing posts with label eclipse. Show all posts
Showing posts with label eclipse. Show all posts
Friday, January 15, 2010
Cloud, rains likely to mar solar eclipse watch
Eager sky watchers awaiting the longest annular solar eclipse of this millennium on Friday are likely to be greeted by partly cloudy sky and isolated rains.
An India Meteorological Department (IMD) outlook said that these less than promising “eclipse watch” conditions would prevail along an arc extending right from the country's northeast to southwest.
The partial cloud cover may in this manner hang over Arunachal Pradesh, West Bengal, Sikkim, Orissa, Andhra Pradesh, Karnataka, Tamil Nadu, Kerala, Lakshadweep and the Andaman and Nicobar Islands.
Cloud Cover
The Satish Dhawan Space Centre (SDSC) at Sriharikota and the Thumba Equatorial Rocket Launching Station (Terls) at the Vikram Sarabhai Space Centre where elaborate arrangements have been made to track the celestial spectacle are expected to variously fall under the cloud cover on the appointed day.
With one day to go, satellite pictures on Wednesday showed the presence of a bank of massive clouding off Indonesia and adjoining east Indian Ocean and southeast Bay of Bengal looking threateningly at Sri Lanka and southern Indian peninsula.
Meanwhile, minimum temperatures over the Indo-Gangetic plains were below normal by 2 to 5 deg Celsius over parts of west Rajasthan and the Indo-Gangetic plains. Maximum temperatures were appreciably below normal over most parts of Punjab, Haryana, Delhi, Uttar Pradesh, Bihar, sub-Himalayan West Bengal, Assam, Meghalaya and isolated pockets of west Rajasthan.
Cold day conditions continued to prevail over most parts of Punjab, Haryana, Delhi, Uttar Pradesh and Bihar and extended eastwards over sub-Himalayan West Bengal, Assam and Meghalaya.
Rains Over North-west
Isolated to scattered rainfall has occurred over most parts of northwest and central India and snowfall over western Himalayan region.
This is even as a trough in mid-tropospheric westerlies is expected to affect the western Himalaya region during the next 24 hours.
The trough represents a low-pressure area with ascending motion of air, which on cooling falls down as either or snow, depending on the respective altitudes.
The IMD has forecast scattered rainfall to continue over parts of plains of northwest and adjoining central India until Wednesday evening. Isolated to scattered rainfall activity over east India during the next two days.
Forecast up to Saturday spoke about the possibility of fog to very dense fog conditions in the morning hours over the plains of northwest India during next 24 hours and over entire Indo-Gangetic plains thereafter.
A slight rise has been indicated in maximum temperatures over the Indo-Gangetic plains from Thursday onwards. But cold day conditions may continue to occur over some parts of the plains during the next two days.
The minimum temperatures are expected to fall over northwest and central India during next three days as the westerly system moves east yielding space for cold northerly to northwesterlies.
Meanwhile, an easterly wave has been affecting south peninsular India over the past two days. This has also triggered confluence of opposing winds over central and east India, which would continue for the next two days as well.
According to the Chennai Regional Met Centre, rainfall has been reported from a few places over interior Karnataka over the past 24 hours.
Isolated rainfall occurred over coastal Andhra Pradesh, Telangana, Kerala, Lakshadweep, Tamil Nadu and coastal Karnataka as the rains propagated north-northeast into the interior. Bellary recorded a heavy rainfall of seven cm during this period.
Forecast until Friday spoke about the possibility of further rains at a few places over Andhra Pradesh. Isolated rain has been forecast over Tamil Nadu, Puducherry, Kerala, Lakshadweep, south interior Karnataka, coastal and north interior Karnataka.
An outlook by the US National Centres for Environmental Prediction continued to predict that the scattered rainfall over the peninsula would continue until January 20.
An India Meteorological Department (IMD) outlook said that these less than promising “eclipse watch” conditions would prevail along an arc extending right from the country's northeast to southwest.
The partial cloud cover may in this manner hang over Arunachal Pradesh, West Bengal, Sikkim, Orissa, Andhra Pradesh, Karnataka, Tamil Nadu, Kerala, Lakshadweep and the Andaman and Nicobar Islands.
Cloud Cover
The Satish Dhawan Space Centre (SDSC) at Sriharikota and the Thumba Equatorial Rocket Launching Station (Terls) at the Vikram Sarabhai Space Centre where elaborate arrangements have been made to track the celestial spectacle are expected to variously fall under the cloud cover on the appointed day.
With one day to go, satellite pictures on Wednesday showed the presence of a bank of massive clouding off Indonesia and adjoining east Indian Ocean and southeast Bay of Bengal looking threateningly at Sri Lanka and southern Indian peninsula.
Meanwhile, minimum temperatures over the Indo-Gangetic plains were below normal by 2 to 5 deg Celsius over parts of west Rajasthan and the Indo-Gangetic plains. Maximum temperatures were appreciably below normal over most parts of Punjab, Haryana, Delhi, Uttar Pradesh, Bihar, sub-Himalayan West Bengal, Assam, Meghalaya and isolated pockets of west Rajasthan.
Cold day conditions continued to prevail over most parts of Punjab, Haryana, Delhi, Uttar Pradesh and Bihar and extended eastwards over sub-Himalayan West Bengal, Assam and Meghalaya.
Rains Over North-west
Isolated to scattered rainfall has occurred over most parts of northwest and central India and snowfall over western Himalayan region.
This is even as a trough in mid-tropospheric westerlies is expected to affect the western Himalaya region during the next 24 hours.
The trough represents a low-pressure area with ascending motion of air, which on cooling falls down as either or snow, depending on the respective altitudes.
The IMD has forecast scattered rainfall to continue over parts of plains of northwest and adjoining central India until Wednesday evening. Isolated to scattered rainfall activity over east India during the next two days.
Forecast up to Saturday spoke about the possibility of fog to very dense fog conditions in the morning hours over the plains of northwest India during next 24 hours and over entire Indo-Gangetic plains thereafter.
A slight rise has been indicated in maximum temperatures over the Indo-Gangetic plains from Thursday onwards. But cold day conditions may continue to occur over some parts of the plains during the next two days.
The minimum temperatures are expected to fall over northwest and central India during next three days as the westerly system moves east yielding space for cold northerly to northwesterlies.
Meanwhile, an easterly wave has been affecting south peninsular India over the past two days. This has also triggered confluence of opposing winds over central and east India, which would continue for the next two days as well.
According to the Chennai Regional Met Centre, rainfall has been reported from a few places over interior Karnataka over the past 24 hours.
Isolated rainfall occurred over coastal Andhra Pradesh, Telangana, Kerala, Lakshadweep, Tamil Nadu and coastal Karnataka as the rains propagated north-northeast into the interior. Bellary recorded a heavy rainfall of seven cm during this period.
Forecast until Friday spoke about the possibility of further rains at a few places over Andhra Pradesh. Isolated rain has been forecast over Tamil Nadu, Puducherry, Kerala, Lakshadweep, south interior Karnataka, coastal and north interior Karnataka.
An outlook by the US National Centres for Environmental Prediction continued to predict that the scattered rainfall over the peninsula would continue until January 20.
Monday, January 11, 2010
On Jan 15, watch the ring of fire
In a week, a rare celestial event will mesmerise skygazers in southern Tamil Nadu and parts of Kerala. A ring of fire will adorn the afternoon sky
over Dhanushkodi near Rameswaram, Thiruvananthapuram, Tirunelveli, Nagercoil, Kanyakumari, Madurai, Thanjavur and Nagapattinam for 10 minutes on January 15, making it the first annular solar eclipse to be seen from India in 45 years. The rest of India will have a partial sighting.
An annular solar eclipse happens when the disc of the moon covers the central part of the sun, leaving only a ring-like peripheral region visible from some parts of the earth. This happens when the earth comes closest to the sun while the moon is at its farthest position in orbit. In such a situation, the disc of the moon cannot completely cover the sun's surface and a fiery ring is visible beyond the moon's edge. The last time an annular eclipse was viewed from India was on November 23, 1965. The next one will be on December 26, 2019.
The track of annularity, or the patch of land from where this celestial event can be viewed, will start from Africa and cross the Indian Ocean to end at Shandong Peninsula in China. "The temple town of Rameswaram will lie very close to the central line and the annularity there can be seen for a duration of 10 minutes and 7 seconds starting at 1.17 pm and ending at 1.25 pm. This is a very long period given the average durations of annular eclipses," said M P Birla Planetarium director (research & academic) Debi Prosad Duari.
over Dhanushkodi near Rameswaram, Thiruvananthapuram, Tirunelveli, Nagercoil, Kanyakumari, Madurai, Thanjavur and Nagapattinam for 10 minutes on January 15, making it the first annular solar eclipse to be seen from India in 45 years. The rest of India will have a partial sighting.
An annular solar eclipse happens when the disc of the moon covers the central part of the sun, leaving only a ring-like peripheral region visible from some parts of the earth. This happens when the earth comes closest to the sun while the moon is at its farthest position in orbit. In such a situation, the disc of the moon cannot completely cover the sun's surface and a fiery ring is visible beyond the moon's edge. The last time an annular eclipse was viewed from India was on November 23, 1965. The next one will be on December 26, 2019.
The track of annularity, or the patch of land from where this celestial event can be viewed, will start from Africa and cross the Indian Ocean to end at Shandong Peninsula in China. "The temple town of Rameswaram will lie very close to the central line and the annularity there can be seen for a duration of 10 minutes and 7 seconds starting at 1.17 pm and ending at 1.25 pm. This is a very long period given the average durations of annular eclipses," said M P Birla Planetarium director (research & academic) Debi Prosad Duari.
Thursday, December 31, 2009
After 1741, 2010 to witness lunar eclipse on NEW year day.
On a full blue moon day on Thursday, skywatchers will have a bonanza when they find the lunar radiance, rather dim, as the country witnesses a partial lunar eclipse. The phenomenon, according to astrophysicists, is only the second time since 1741 when the world saw a lunar eclipse on a New Year’s day.
A partial lunar eclipse occurs when only part of the Moon passes through the darkest part of the Earth’s shadow.
The eclipse is scheduled to begin when the Moon enters the Earth’s shadow at 10:47 pm, and it ends at 02:58:11 am. The start of the partial eclipse will be at 00:22:43 am on January 1, 2010. It will end at 01:22:41 am.
“Although the partial phase of the eclipse lasts for an hour, only 7 per cent of the diameter of the Moon is covered by the umbral shadow of the Earth, which is too negligible to be easily visible,” said N Rathnashree, director of Nehru Planetarium.
When a second full moon in a calendar month appears in the night sky, the occurrence is known as a blue moon. There are 12 full moons most years, but every two or three years there is an extra full moon which is called a blue moon.
“Such an eclipse of the Moon will be difficult to discern with naked eye—although an astrophotograph of the Moon might just show a hint of darkening over a very tiny region of the Moon,” Rathnasree said.
According to scientists, the astronomical event can be seen all over Asia and Europe, major parts of Africa and a small portion of southwestern Australia.
“The beginning, the middle and the ending of the eclipse will be visible from all parts of India,” Science Popularisation Association of Communicators and Educators (SPACE) Director C B Devgun said.
The beginning of the umbral phase will be visible from the extreme southeastern part of Australia, middle of South and North Pacific Ocean and extreme Solomon Island. The ending of the umbral phase will be visible from North and South Atlantic Ocean and Greenland.
A partial lunar eclipse occurs when only part of the Moon passes through the darkest part of the Earth’s shadow.
The eclipse is scheduled to begin when the Moon enters the Earth’s shadow at 10:47 pm, and it ends at 02:58:11 am. The start of the partial eclipse will be at 00:22:43 am on January 1, 2010. It will end at 01:22:41 am.
“Although the partial phase of the eclipse lasts for an hour, only 7 per cent of the diameter of the Moon is covered by the umbral shadow of the Earth, which is too negligible to be easily visible,” said N Rathnashree, director of Nehru Planetarium.
When a second full moon in a calendar month appears in the night sky, the occurrence is known as a blue moon. There are 12 full moons most years, but every two or three years there is an extra full moon which is called a blue moon.
“Such an eclipse of the Moon will be difficult to discern with naked eye—although an astrophotograph of the Moon might just show a hint of darkening over a very tiny region of the Moon,” Rathnasree said.
According to scientists, the astronomical event can be seen all over Asia and Europe, major parts of Africa and a small portion of southwestern Australia.
“The beginning, the middle and the ending of the eclipse will be visible from all parts of India,” Science Popularisation Association of Communicators and Educators (SPACE) Director C B Devgun said.
The beginning of the umbral phase will be visible from the extreme southeastern part of Australia, middle of South and North Pacific Ocean and extreme Solomon Island. The ending of the umbral phase will be visible from North and South Atlantic Ocean and Greenland.
"Blue Moon" to Shine on New Year's Eve
For the first time in almost 20 years, a bright "blue moon" will grace New Year's Eve celebrations worldwide. (Take a moon myths quiz.)
If the skies are clear, revelers looking up at midnight will get an eyeful of the second full moon of the month—commonly called a blue moon. The last time a blue moon appeared on New Year's Eve was in 1990, and it won't happen again until 2028.
With this New Year's Eve blue moon, "there is nothing scientific about it, and it has no astronomical significance," said Mark Hammergren, a staff astronomer at the Adler Planetarium in Chicago, Illinois.
"But I believe it does give us some insight into history and makes us think of how our calendar system has derived from motions of objects in the sky."
Blue Moon Error
The popular definition of a blue moon isn't the only one—and it's one that's based on an editorial error, astronomers contend.
The widespread definition of the second full moon in a month stems from errors made in an astronomy magazine, when a writer misinterpreted how the term was used in the Maine Farmer's Almanac.
Later studies of almanacs published from 1819 to 1962 revealed that the term "blue moon" actually refers to the "extra" full moon that can occur in a year due to differences between the calendar year and the astronomical year.
(Related: "Leap Year—How the World Makes Up for Lost Time.")
Most years on average have 12 full moons, with 1 appearing each month.
That's because the lunar month—the time it takes the moon to cycle through its phases—corresponds closely to the calendar month.
But the calendar year is actually based on the solar cycle, or the time it takes Earth to make one trip around the sun. This means a year is not evenly divisible by lunar months, so every three years or so there are 13 full moons.
The farmer's almanac further divided the year into four seasons, with each season lasting three months. When a given season saw four full moons, the almanac dubbed the third moon as a blue moon.
Ultimately, a blue moon as defined by the calendar isn't that rare, added Hammergren. The term's significance instead lies in the way it links people to the motions of the cosmos.
"Just being able to recognize that we can have a full moon twice in a month and have [folklore] attached really highlights the fact that humans have been astronomers their entire existence," he said.
"True" Blue Moon
Before the editorial error, the term "blue moon" more often referred to the rare instances when the moon actually seemed to turn blue, as can happen under certain atmospheric conditions.
"After a forest fire or volcanic eruption, there may be enough particulate matter in the air so that the moon can take on a bluish tinge," Hammergren said.
For instance, a "true" blue moon occurred in 1950 after a large forest fire in Canada blew smoke across most of the Northern Hemisphere.
Another appeared in 1980 after the last major eruption of Mount St. Helens, which sent tons of ash into the upper atmosphere.
Although rumblings at the Mayon Volcano in the Philippines seem to signal a major eruption is imminent, experts don't think Mayon's current output will make this New Year's Eve full moon turn blue.
Howling at the Blue Moon
Even if the 2009 New Year's Eve blue moon has astronomers scoffing, nighttime partygoers may still get moonstruck.
Rising in the east at sunset, the New Year's Eve full moon will reach its highest point at midnight, noted Jack Horkheimer, director of the Miami Space-Transit Planetarium and host of PBS television's long-running show Star Gazer.
"Full moons around winter solstice rise their highest for the entire year," Horkheimer added.
"Even if you are downtown in a large city, if it is clear at the stroke of midnight the moon will be very visible if you look up."
In any location, the high, silvery orb will seem like a floodlight cast on the landscape, added Horkheimer, who is organizing a national moon-howling contest around this year's blue moon.
"This is especially true where the ground is covered with a blanket of snow. There is nothing quite so spectacular as a snow-covered scene under a December full moon at midnight."
From National Geographic
If the skies are clear, revelers looking up at midnight will get an eyeful of the second full moon of the month—commonly called a blue moon. The last time a blue moon appeared on New Year's Eve was in 1990, and it won't happen again until 2028.
With this New Year's Eve blue moon, "there is nothing scientific about it, and it has no astronomical significance," said Mark Hammergren, a staff astronomer at the Adler Planetarium in Chicago, Illinois.
"But I believe it does give us some insight into history and makes us think of how our calendar system has derived from motions of objects in the sky."
Blue Moon Error
The popular definition of a blue moon isn't the only one—and it's one that's based on an editorial error, astronomers contend.
The widespread definition of the second full moon in a month stems from errors made in an astronomy magazine, when a writer misinterpreted how the term was used in the Maine Farmer's Almanac.
Later studies of almanacs published from 1819 to 1962 revealed that the term "blue moon" actually refers to the "extra" full moon that can occur in a year due to differences between the calendar year and the astronomical year.
(Related: "Leap Year—How the World Makes Up for Lost Time.")
Most years on average have 12 full moons, with 1 appearing each month.
That's because the lunar month—the time it takes the moon to cycle through its phases—corresponds closely to the calendar month.
But the calendar year is actually based on the solar cycle, or the time it takes Earth to make one trip around the sun. This means a year is not evenly divisible by lunar months, so every three years or so there are 13 full moons.
The farmer's almanac further divided the year into four seasons, with each season lasting three months. When a given season saw four full moons, the almanac dubbed the third moon as a blue moon.
Ultimately, a blue moon as defined by the calendar isn't that rare, added Hammergren. The term's significance instead lies in the way it links people to the motions of the cosmos.
"Just being able to recognize that we can have a full moon twice in a month and have [folklore] attached really highlights the fact that humans have been astronomers their entire existence," he said.
"True" Blue Moon
Before the editorial error, the term "blue moon" more often referred to the rare instances when the moon actually seemed to turn blue, as can happen under certain atmospheric conditions.
"After a forest fire or volcanic eruption, there may be enough particulate matter in the air so that the moon can take on a bluish tinge," Hammergren said.
For instance, a "true" blue moon occurred in 1950 after a large forest fire in Canada blew smoke across most of the Northern Hemisphere.
Another appeared in 1980 after the last major eruption of Mount St. Helens, which sent tons of ash into the upper atmosphere.
Although rumblings at the Mayon Volcano in the Philippines seem to signal a major eruption is imminent, experts don't think Mayon's current output will make this New Year's Eve full moon turn blue.
Howling at the Blue Moon
Even if the 2009 New Year's Eve blue moon has astronomers scoffing, nighttime partygoers may still get moonstruck.
Rising in the east at sunset, the New Year's Eve full moon will reach its highest point at midnight, noted Jack Horkheimer, director of the Miami Space-Transit Planetarium and host of PBS television's long-running show Star Gazer.
"Full moons around winter solstice rise their highest for the entire year," Horkheimer added.
"Even if you are downtown in a large city, if it is clear at the stroke of midnight the moon will be very visible if you look up."
In any location, the high, silvery orb will seem like a floodlight cast on the landscape, added Horkheimer, who is organizing a national moon-howling contest around this year's blue moon.
"This is especially true where the ground is covered with a blanket of snow. There is nothing quite so spectacular as a snow-covered scene under a December full moon at midnight."
From National Geographic
Wednesday, December 30, 2009
Going to be once in a "blue" moon
Sky gazers await once in a blue moon phenomenon on New Year's eve. Announcing this to reporters in Chennai today, Director of Birla Planetarium P Iyamperumal said the lunar eclipse on 31 December can be viewed in Chennai and the annual solar eclipse on 15 January, a rare happening after 108 years, can be viewed from Kanyakumari.
'The lunar eclipse will take place from 12.21 pm to 1.24 am. About 80 per cent of the eclipse can be viewed from Chennai. It can be watched with the naked eye,' he said.
.
Stating that special arrangements had been made at the planetarium to watch the eclipse, he said an exclusive goggle is needed for the purpose.
Meanwhile, an agency report from New Delhi said when a second full moon in a calendar month appears in the night sky, the occurrence is known as a blue moon.
There are 12 full moons most years but every two or three years there is an extra full moon which is called a blue moon.
'We've already had a full moon on 2 December and the next one is on New Year’s Eve that is on 31 December,' Science Popularisation Association of Communicators and Educators (SPACE) president C B Devgun said.
On rare occasions the moon actually had a blue appearance - often caused by smoke from large-scale fires or excessive dust particles in the atmosphere.
Explaining the phenomena of bue moons, Devgun said the moon cycle takes about 29.53 days to complete that is almost a month. That is why there's one full moon once a month, at least on most years.
'Because the lunar cycle does not reach a full 30 days, the full moon happens about a half-a-day earlier each month. So over time, this small difference eventually pushes the date of the full moon until there can be two full moons in one month. When this happens, the second full moon in that month is called the blue moon,' Devgun said.
This comes about quite rarely, only about seven times in 19 years, which is equal to one blue moon every 2.7 years more or less.
The next blue moon will occur on 21 November, 2010. After that, planet watchers will have to wait until 21 August, 2013, to see another blue moon.
'The lunar eclipse will take place from 12.21 pm to 1.24 am. About 80 per cent of the eclipse can be viewed from Chennai. It can be watched with the naked eye,' he said.
.
Stating that special arrangements had been made at the planetarium to watch the eclipse, he said an exclusive goggle is needed for the purpose.
Meanwhile, an agency report from New Delhi said when a second full moon in a calendar month appears in the night sky, the occurrence is known as a blue moon.
There are 12 full moons most years but every two or three years there is an extra full moon which is called a blue moon.
'We've already had a full moon on 2 December and the next one is on New Year’s Eve that is on 31 December,' Science Popularisation Association of Communicators and Educators (SPACE) president C B Devgun said.
On rare occasions the moon actually had a blue appearance - often caused by smoke from large-scale fires or excessive dust particles in the atmosphere.
Explaining the phenomena of bue moons, Devgun said the moon cycle takes about 29.53 days to complete that is almost a month. That is why there's one full moon once a month, at least on most years.
'Because the lunar cycle does not reach a full 30 days, the full moon happens about a half-a-day earlier each month. So over time, this small difference eventually pushes the date of the full moon until there can be two full moons in one month. When this happens, the second full moon in that month is called the blue moon,' Devgun said.
This comes about quite rarely, only about seven times in 19 years, which is equal to one blue moon every 2.7 years more or less.
The next blue moon will occur on 21 November, 2010. After that, planet watchers will have to wait until 21 August, 2013, to see another blue moon.
Longest annular eclipse of the sun on Jan15
Sky enthusiasts in India, especially in Tamil Nadu, will have a rare opportunity to witness the longest annular eclipse of the sun, occurring on Jan 15 next.
"The annular phase runs from 10.44 am (IST),when the eclipse begins in the Central African Republic to the end of the eclipse on the Chinese Yellow Sea coast at 14.29 pm (IST)," Tamilnadu Science and Technology Centre Executive Director Dr P Iyamperumal told PTI today.
He said the maximum duration of annularity would reach 11 min 08 sec over Indian Ocean thus making it the longest annular eclipse.
Stating that this was a rare event happening about 108 years in Tamil Nadu, he said ""the annular eclipse will be visible from Kanyakumari, Nagercoil, Tirunelveli, Tenkasi, Tuticorin, Rameshwaram, Madurai, Rajapalayam, Sivaganga, Karikudi, Pudukottai, Nagapatinam, Tanjavur, Kumbakonam, Mayiladuthurai and Chidambaram".
"The annular phase runs from 10.44 am (IST),when the eclipse begins in the Central African Republic to the end of the eclipse on the Chinese Yellow Sea coast at 14.29 pm (IST)," Tamilnadu Science and Technology Centre Executive Director Dr P Iyamperumal told PTI today.
He said the maximum duration of annularity would reach 11 min 08 sec over Indian Ocean thus making it the longest annular eclipse.
Stating that this was a rare event happening about 108 years in Tamil Nadu, he said ""the annular eclipse will be visible from Kanyakumari, Nagercoil, Tirunelveli, Tenkasi, Tuticorin, Rameshwaram, Madurai, Rajapalayam, Sivaganga, Karikudi, Pudukottai, Nagapatinam, Tanjavur, Kumbakonam, Mayiladuthurai and Chidambaram".
Sunday, August 02, 2009
Tuesday, July 21, 2009
Monday, July 20, 2009
Subscribe to:
Posts (Atom)