WEEKEND METEOR SHOWER: Today Earth is entering a stream of debris from Halley’s comet, source of the annual Orionid meteor shower. Forecasters expect the shower to peak on Saturday morning, Oct. 22nd, with more than 15 meteors per hour. Check http://spaceweather.com for links to a live meteor radar, sky maps and observing tips.
Taken from Nasa’s Science News Website:
Oct. 4, 2011: On October 8th Earth is going to plow through a stream of dust from Comet 21P/Giacobini-Zinner, and the result could be an outburst of Draconid meteors.
“We’re predicting as many as 750 meteors per hour,” says Bill Cooke of NASA’s Meteoroid Environment Office. “The timing of the shower favors observers in the Middle East, north Africa and parts of Europe.”
Every 6.6 years Comet Giacobini-Zinner swings through the inner solar system. With each visit, it lays down a narrow filament of dust, over time forming a network of filaments that Earth encounters every year in early October.
“Most years, we pass through gaps between filaments, maybe just grazing one or two as we go by,” says Cooke. “Occasionally, though, we hit one nearly head on–and the fireworks begin.”
“British astronomers have announced the discovery of a supernova in
galaxy M101, which they claim is the nearest supernova of its type for
more than 40 years. The object was discovered at magnitude 17, but
it appears to be rising in brightness, and the team says that it could
become as bright as magnitude 10 within the next few days. That
would bring it well within the reach of small telescopes and even
large binoculars. Amateur astronomers with suitable instruments
should already be able to photograph the supernova, which has the
name PTF11kly. Its position is RA 14:03:05.81, Dec +54:16:25.4.
M101 is currently well placed for observation; it is in Ursa Major,
not far from the well-known stars Mizar and Alkaid/Benetnasch in the
Plough.The supernova was first seen on August 24 at around 8 pm BST,
within the spiral arms of M101. An image taken the previous night
had shown no such object in that position. The discovery was made
from Palomar with the 48-inch Schmidt telescope, which is now operated
robotically by a team of British and American astronomers known as
the Palomar Transient Factory. The object’s spectrum shows that it
appears to be a Type 1a supernova, which occurs when a white-dwarf
star in a binary system explodes.
Supernova M101To find distances in space, astronomers use objects called “standard candles.” Standard candles are objects that give a certain, known amount of light. Because astronomers know how bright these objects truly are, they can measure their distance from us by analyzing how dim they appear. For example, say you’re standing on a street evenly lined with lampposts. According to a formula known as the inverse square law, the second streetlamp will look one-fourth as bright as the first streetlamp, and the third streetlamp will look one-ninth as bright as the first streetlamp, and so on. By judging the dimness of their light, you can easily guess how far away the streetlamps are as they stretch into the distance. For short distances in space — within our galaxy or within our local group of nearby galaxies — astronomers use a type of star called a Cepheid variable as a standard candle. These young stars pulse with a brightness that tightly relates to the time between pulses. By observing the way the star pulses, astronomers can calculate its actual brightnessBut beyond the local group of galaxies, telescopes can’t make out individual stars. They can only discern large groups of stars. To measure distances to far-flung galaxies, therefore, astronomers need to find incredibly bright objects. So astronomers turn to exploding stars, called supernovae. Supernovae, which occur within a galaxy about every 100 years, are among the brightest events in the sky. When a star explodes, it releases so much energy that it can briefly outshine all the stars in its galaxy. In fact, we can sometimes see a supernova occur even if we can’t see its home galaxy. To determine distances, astronomers use a certain type of exploding star called a Type Ia supernova. Type Ia supernovae occur in a binary system — two stars orbiting one another. One of the stars in the system must be a white dwarf star, the dense, carbon remains of a star that was about the size of our Sun. The other can be a giant star or even a smaller white dwarf. White dwarf stars are one of the densest forms of matter, second only to neutron stars and black holes. Just a teaspoon of matter from a white dwarf would weigh five tons. Because white dwarf stars are so dense, their gravity is particularly intense. The white dwarf will begin to pull material off its companion star, adding that matter to itself. When the white dwarf reaches 1.4 solar masses, or about 40 percent more massive than our Sun, a nuclear chain reaction occurs, causing the white dwarf to explode. The resulting light is 5 billion times brighter than the Sun. Because the chain reaction always happens in the same way, and at the same mass, the brightness of these Type Ia supernovae are also always the same. The explosion point is known as the Chandrasekhar limit, after Subrahmanyan Chandrasekhar, the astronomer who discovered it. To find the distance to the galaxy that contains the supernova, scientists just have to compare how bright they know the explosion should be with how bright the explosion appears. Using the inverse square law, they can compute the distance to the supernova and thus to the supernova’s home galaxy.
UPDATE: Supernova in Messier 101 brightens Could be Binocular target in 1 week!
See The Bad Astronomer’s Blog Update !
BowFest Information Booth and Public Solar Viewing
We are going to have an information table at BowFest this coming Saturday. Sol, our sun, will be on display today for telescopic viewing with an 8 inch Sky Watcher Dobsonian telescope. It will be equipped with a special viewing safety device called a “mylar sun filter” graciously loaned to us for the occasion by Robert Ballantyne, of Governance Corporation. .
Even if there are clouds, the sun can still be seen through the telescope. As long as they are not too thick, so we can “almost” say with certainty, that this will be a rain or shine observing event! There is a tale of one astronomer, Fritz Zwicky, from the Mount Wilson Observatory in California, who was known to have his assistants fire a 22 rifle into the sky in an attempt to improve the less than ideal seeing conditions during his observing runs! We however, will only resort to well wishes, perhaps a polite curse or 2, and a few hail Mary’s…
What can one expect to see through a mylar sun filter? Well, we should see a greyish-silver disc with several black spots across the surface. How many spots seen will depend upon where we are in the 11 year solar cycle. The last minimum was back in 2008 so very few are visible at the present moment. Here is a picture of what the sun looked like today, and is an approximate representation of what we might expect to see on Saturday. You can check the daily sunspot cycle at Space Weather.com, my favorite website for listing all current astronomical phenomena. You can even subscribe to text msg alerts on your cellphone for special celestial events! A look at the NASA’s Solar and Heliospheric Observatory website gives RRS feeds with daily solar weather and information as well. There is excellent software for viewing the SOHO images and information called JHelioviewer. These are the very best tools for the solar and armchair observer bar none! But for a real-time, live 3D view of what’s happening on the sun you can come down and see us at BowFest this Saturday.
Don’t miss it!
Special News & Membership Call Out!
We need volunteers and new members! We are extremely blessed to have been offered the privileged opportunity of having access to the use of an 17.5 inch reflecting Observatory Class Telescope on Bowen Island by a former director of the Manitoba Planetarium, Robert Ballantyne! This mirror in this telescope was built some 26 years ago by Robert and his 2 colleagues for use by the Manitoba Astronomy Club.
Does this sound too good to be true?!? Well, there are a couple of prerequisites before we get to enjoy observing time on this wonderful instrument. Volunteers & members showing dedication to learning astronomy, who have taken the astronomy course and can show proficiency in telescope use and observing skills will be rewarded with observing time on this fine instrument. It doesn’t get any better than this! We are going to need a small army of volunteers to make this project a reality, so hop on board and help us make this beautiful & rare opportunity a reality!
Basic Astronomy Course
We will soon be offering a basic astronomy course for individuals looking to start learning about the night sky. We will also have a signup sheet for anyone interested in taking the basic astronomy course in the not-too-distant future. Some of the topics covered will be identifying the stars and constellations, folk lore, science history, observing techniques, binocular astronomy; basic telescope use, design & maintenance, with a section on how to purchase the right binoculars & telescopes.
Dates, times, costs and location to be announced after we find out how many people & the level of knowledge of those interested in participating.
Call David @ 9064 for more information
Clear Skies & Happy Star Trails to You!
This is a final reminder for tonight’s Perseid Meteor Shower Star Party. This is a great family event not to be missed. We will be arriving around 10:30PM tonight near dusk, to get a good spot near the Equestrian riding stables by Terminal Creek in the Crippen Park Meadows. Come on down and join the the fun and watch the summers best falling star show! I have obtained a medium – sized telescope for people to view the sky with, and am hoping others will bring there telescopes, binoculars etc to watch the skies as well. Help us kick off Bowen Islands very first Astronomy Club organizing event!
The following links contain the Star Charts for this evenings sky. Feel free to print a copy before coming down, or get one when you arrive. I have printed off a small number to hand out to participants.
Don’t miss the Greatest Show Off Earth…We hope to see you there!
Clear Skies to us all!
Bowen Island Astronomy Club Presents:
First Annual Perseid Meteor Shower Star Party!
Come and join the Bowen Island Astronomy Clubs first annual star party!
We will be gathering to watch the greatest show off earth, the summertime annual Perseid Meteor Shower!
The meteor shower will peak on the night of Friday the 12th, with falling star counts predicted to possibly be as high as 100 meteors per hour! This is the best meteor shower of many throughout the year so please come down and join us at the Crippen Park horse riding area at approximately 10:30 PM. Bring lawn chairs, blankets or matts to lay on, hot chocolate or coffee,snacks, blankets to keep warm, bug spray, your binoculars and telescopes if you have them as this an excellent large sky and dark spot on Bowen Island. Please keep your flashlights pointed at the ground when you arrive so we can keep our eyes dark adapted to better see the fainter meteors.
This is a family event with an emphasis on sharing, learning, and appreciating the beauty that nature has to offer us. Do please look up and be alert for Perseid meteors, during the hours of darkness in the nights before and after.
All Volunteers and Organizers Welcome!
Please contact David Wilde (email@example.com)
Don’t miss the greatest show off earth!
We hope to see you there!
(This is a fair-weather event & will be cancelled if rain or full on cloud obscure the view)