Wandering through the realms of the cosmos, pondering its huge vastness

Posts tagged “summer triangle

A Dark Moonless Night for the 2012 Lyrids

The New Moon this month will guarantee the perfect dark sky to watch the Ancient April “shooting stars” called the Lyrid Meteor Shower or the Lyrids.

The Lyrids fall from Comet C1861 G1 Thatcher as the Earth passes through her tail. Activity from this meteor shower can be observed from 16 April to 25 April, but the perfect time to catch the Lyrids is during late night of the 21st to the early morning of the 22nd.

The Lyrids can offer a display of 10 to 20 per hour or have a surge of activity of up to 100 per hour.

The Lyrids, so named because they appear to originate from the constellation Lyra (The Lyre), have been observed in the night sky during mid-April for at least 2,500 years, NASA scientists say. On 21 – 22 of April you can see Lyra rise at around 11PM (local time) from the north east and continue to rise high into the sky towards the south east during the darkest hours of the night sky.

A screencap from Stellarium showing the radiant of the Lyrids located near the star Vega of the constellation Lyra.

The fifth-brightest star of the sky, alpha Lyr, called Vega (arabic for “stone eagle”), radiates from the top of Lyra with a pure white colour. Together with alpha Cyg, Deneb , and alpha Aql, Atair, Vega forms the famous asterism, the Summer Triangle (shown above).

Lyrid meteors are usually around magnitude +2, which is bright enough to be visible from most cities, but you’ll see more and enjoy them more if you leave the city for a less light-polluted area where the stars shine brighter. They often produce luminous trains of dust that can be observed for several seconds. Some Lyrids will be brighter, though, and the occassional “fireball” can cast shadows for a split second and leave behind glowing, smoky debris trails that last for minutes.

So, how do you watch these meteors? Like any other meteor shower event, watching the Lyrids requires no special viewing equipment like binoculars or  telescopes. All you need is an open sky and a place to lie down and relax. Someplace dark, away from trees and buildings is best. Meteors zip across the sky, so the more sky you see the better.  Gaze into the stars, and be patient. The best direction to watch is wherever your sky is darkest, usually straight up, perhaps with a little inclination toward the radiant.

As an observer, you can make a careful meteor count and report it to the International Meteor Organization. Such counts are analyzed to yield the shower’s zenithal hourly rate (ZHR), which is the number of meteors that a single observer would see per hour under ideal conditions: with the radiant directly overhead (at the zenith) and the sky dark enough to reveal 6.5-magnitude stars.

Meteors Without Borders: #LyridsWatch

During Global Astronomy Month (GAM 2012), everyone is encouraged to observe the Lyrids and send in the reports of what they saw. You can also share your data by tweeting your postcode, your country (click here to find your country code) and, optionally, the meteor count along with the hashtag; #MeteorWatch (you are welcome to use GAM hastags as well – #GAM2012 #LyridsWatch)

The meteor data will appear in a map at MeteorWatch.org. This is an excellent way to get more immersed and socialize during your observations.

Observe the Lyrids with UP Astrosoc

For Philippine observers located near Quezon City, the University of the Philippines Astronomical Society (UP AstroSoc) invites you to its Lyrids observation on April 21-22, 9PM-6AM at the PAGASA Astronomical Observatory Sundeck (located within the UP Diliman Campus).

The event is for free and open to all, so feel free to bring along with you your friends and family.

For more information, please visit UP Astrosoc’s Facebook fanpage.

Meteor showers can be a lot of fun, so I hope you see some good ones this coming weekend!  Clear skies!

Advertisements

Triangles of the Night Sky

Here are images of the two famous triangles of the night sky — the Summer Triangle and the Winter Triangle — that I took last October.

Winter Triangle - October 5, 2011 3:42 am. This triangle is formed by the three first magnitude stars Sirius in Canis Major, Procyon in Canis Minor, and Betelgeuse in Orion. This shape is a nearly perfect equilateral triangle.

Summer Triangle - October 4, 2011 11:00 pm. This asterism sets in the west shortly after sunset around now. It consists of three bright stars: Vega in the constellation Lyra, Deneb in the constellation Cygnus, and Altair in the constellation Aquila.

These two serve as a stellar calendar, marking the seasons.

The Summer Triangle is the signature star formation of summer. Likewise, the Winter Triangle is a landmark of the winter night sky.

Though December is just around the corner, the Summer Triangle still lights up these autumn evenings. It will continue to shine after dark throughout December and January.

Meanwhile, as the Summer Triangle descends in the west around mid-evening, the Winter Triangle can be seen rising in the east.

Isn’t it amazing that these stars that make up these celestial triangles just happen to be positioned the way they are in the night sky? 🙂

Both photos were taken from our suburban place in San Jose del Monte, Bulacan. 


Constellation Hopping and The Planets this month — September 2010

Highlights:

* Venus, Mars and Spica together in evening sky at start of month
* The above 3 joined by the Moon on the 11th
* Jupiter at opposition (21st) with Full Moon (23rd) and Uranus nearby
* Mercury bright in the morning sky



Western sky view a few minutes after sunset on September 11 – the thin crescent moon joins the celestial trio of Venus, Mars and Spica (brightest star of Virgo)

Philippine nights will be longer as the Sun approaches the celestial equator. Autumnal equinox will occur on September 23 when day and night will have approximately equal length on Earth.This point is also called as First point of Libra.

The rich band of constellations and stars along the Milky Way from the constellations Cygnus, the Swan, in the north to Sagittarius and Scorpius in the south, begin to give way this month to fainter constellations, many of them with watery associations such as the constellations of Capricornus, the Sea Goat, Aquarius, the Water Bearer and Pisces the Fish. The famous asterism Teapot in the sky in the constellation of Sagittarius can be observed at about 40 to 47 degrees above the southern horizon, an hour after sunset as shown below.

View of the eastern sky on September 7 at 4:00 AM (PST)

Betelgeuse, the super giant red star and the prominent star of the famous constellation Orion, the Mighty Hunter, will be located at about 25 degrees to the upper right of Mars. Sirius, the brightest star in the sky of the constellation Canis Major, the Big Dog, will be an easy target as it glows below the constellation of Orion. Procyon, the brightest star of the constellation Canis Minor, the Little Dog, can be located at the lower left of Canis Major. By drawing an imaginary line among the bright stars of these constellations, an equilateral triangle will be formed called the Winter Triangle as shown here:

Southern sky at 7:25 PM (PST)

Also, flying high in this month’s sky is the mythical winged horse Pegasus. Although one of the largest constellations in area, it boasts no bright stars. Its most noticeable star pattern is the Great Square of Pegasus: four second magnitude stars marking the body of the horse. Ironically, the brightest of those stars, Alpheratz, isn’t even an official member of the Pegasus constellation, being part of the neighboring constellation Andromeda. The brightest star in Pegasus isn’t part of the Square: it is Enif, the Arabic word for “nose.” It marks the head of Pegasus, off to the west.

As you look further south, you can see Piscis Austrinus, the southern fish, with the only bright star in the region: Fomalhaut. Fomalhaut, which is 25 light-years from Earth, made headlines in 2008 as one of the first stars to observed to have a planet that was directly imaged with telescopes.

To the east of Fomalhaut is another huge dim constellation, Cetus the Whale, with the only other brightest star in the area, Deneb Kaitos, which means the tail of the whale. Cetus also contains the variable star Mira. Currently this star is too faint to be visible with the naked eye, but over the next few months it will start climbing in brightness until it becomes one of the brightest stars in this constellation.

Normally this sea world is a dim and mysterious place, with only one bright star, Fomalhaut. But this year it is enlivened by a visit from the giant planet Jupiter, right on the border between Pisces and Aquarius.


The Planets


The tight grouping of Venus, Mars, Saturn, and Spica ends its spectacular run this month. All four are low in the western sky at nightfall as September begins, but Saturn drops from sight early in the month. Mars and Venus are still in the sky by month’s end, but they shine for only a little while before dropping below the horizon. By that time, however, the night sky’s next-brightest object, the planet Jupiter, is climbing skyward in the east, and will shine brilliantly throughout the night.

Mercury will shine brightly at magnitude -1 as it reaches its greatest elongation west on September 20 (18°  from the Sun). For early risers, Mercury makes its best morning appearance of the year on the second week of September. Look in the constellation of Leo the Lion near his lower foot star, Rho Leonis. The two objects are 20 arcminutes apart on September 16 and 17.

Venus continues to be prominent in the evening sky, though also low for northern hemisphere observers, at around magnitude -4. The crescent Moon, less than 3° away on September 11 will make an attractive pairing. On the 24th, Venus will reach its peak magnitude of -4.6.

Mars is now shining very low in the evening twilight sky. This month +1.5 magnitude Mars starts a few degrees to the upper right of brilliant Venus. Though the planets will slowly move apart they will stay within 7° of each other all month long.On September 11, the Moon will pass with 5° of the planet.

Giant planet Jupiter is now top target for planetary observers, dominating the night sky and rising in the east as it is getting dark at a bright magnitude of -2.9 in Pisces. The planet is putting on a show for those with reasonable sized telescopes, having lost one of its prominent dark belts and with its two red spots in close proximity. On the 21st,  Jupiter will be at opposition,means it will be visible all night long, rising in the evening, reaching its highest elevation around midnight and setting during dawn.

Saturn is located low in the west during evening twilight. By month’s end the +1.0 magnitude planet will be too close to the Sun to be seen easily by most observers. On September 9,the Moon will be within 7° of Saturn.

Uranus will lie within one degree of Jupiter in Pisces between September 12 and 25, making the giant planet a good signpost to finding its more distant cousin. On the 22nd, it will also be at opposition. If given a clear dark sky and no moonlight, it can be spotted with the unaided eye at magnitude of 5.7.

Neptune will be found among the background stars of the constellation Capricornus, the Sea-Goat and will be standing 42 degrees above the east southeastern horizon at around 7:00 PM (PST) on the 19th of the month. A modest size telescope will be needed to observe the bluish planet.

Sporadic Meteors

Sporadic meteors are not part of any known meteor shower. They represent the background flux of meteors. Except for the few days per year when a major shower is active, most meteors that are observed are Sporadics. This is especially true for meteors observed during the evening. During September, 10-16 or so Sporadic meteors can be observed per hour from a dark moonless sky.

Minor Meteor Showers

Minor showers produce so few meteors that they are hard to notice above the background of regular meteors. Information on most of the minor showers will be provided on a weekly basis by Robert Lunsford’s Meteor Activity Outlook this month.

Additional information on these showers and other minor showers not included here can be found at the following sites: Wayne Hally’s and Mark Davis’s NAMN Notes, and the International Meteor Organization’s 2010 Meteor Shower Calendar.


===========================

sources: PAGASA, SPACE.com, Skymania.com, TheTransientSky

The brightest star in Pegasus isn’t part of the Square: it is Enif, the Arabic word for “nose.” It marks the head of Pegasus, off to the west.