Eta Aquarid Meteor Shower May 3-6

Posted on by

Just a reminder that the Eta Aquarid meteor shower will peak this weekend and into early next week, this shower is associated with Halley’s Comet.

The Moon will be a very slim crescent by the time the Eta’s peak on the morning of the 6th May (Monday).

It is advisable that you try to observe at least the morning before and after the peak as the maxima is very broad for this shower and it is quite possible that rates can vary.

The expected Zenith Hourly Rate is around 65 meteors per hour, but realistically this may be much lower, this shower has shown good rates in the past.

Best observing time is from around 3:30am.
The meteors will appear to “radiate” away from the star Eta Aquarii, meteors closer to the radiant will appear much shorter and ones further away will leave longer streaks, of which you can trace the origin back to the radiant.
Any meteor NOT tracing back to the radiant is classified as “sporadic” or could be a member of another shower which might be showing activity.
Some meteors near the radiant will show as a rapid pinpoint flash of light indicating a “head-on” meteor, don’t worry they won’t hit you!

Look for fast (65km/sec) white/yellowish coloured meteors which leave a 2 to 3 second “train” (sometimes longer), ie: the streak left over after the meteor “burns” out.

There will be some early morning International Space Station passes in the NE on the morning of the peak (6th May) at around 4:21am but will keep low (17 degrees) above the horizon!

Thanks to my pal – Chris Wyatt for the reminder and chart!

Lyrids Meteor Shower, peakings around tonight April 23rd.

Posted on by

Head out early tomorrow morning between midnight and dawn to catch the Lyrids Meteor Shower.

The Lyrids radiant is close to the constellation of Lyra (a harp). The constellation rises just after midnight in the southern hemisphere and moves across the northern sky. The Lyrids meteor shower is best viewed after midnight o well before sunrise on 23/24th April. Point your feet towards the northern sky and look about 45 degrees above the horizon. You should see a really bright white star there – this is the blue white star Vega. This shower is caused by the Earth’s atmosphere passing through the dusty pebbly debris left over from Comet Thatcher and has been known to produce spectacular meteors.

So what is a meteor? As a comet (which is a large ball of rock and ice from the outer Solar System) passes by the Sun they become quite heated up and they begin to shed gas, ice, dust particles and rocks which we see as the comets tail. This is left behind as the comet continues on its journey around the Sun.  If the comet’s orbit intersects that of the Earth’s orbit some of material strikes our atmosphere and we see a meteor.

Comet Thatcher also known was discovered by an American amateur astronomer A.E. Thatcher in 1861. This comet was the brightest in over half a century and both head and tail were visible together in broad daylight. Every spring for at least the past 2,700 years, Earth has passed through the trail, thrilling countless sky watchers with the sight of flaming dust and grit. In 1803, it was reported that it looked as if the entire sky was alight with flaming stars.

The Lyrid meteors strike our atmosphere about 95 kilometres above the earth and at speeds of around 49 km/sec or 175,000km per hour and can burn up in some pretty amazing fireballs.

Typical meteoroids which is the name given to meteors before they hit the atmosphere – range in size from grains of sand to walnuts. The bigger they are, the brighter. A meteor that actually hits the ground – a rare event fortunately is called a meteorite.

So if you want to have a look –  find somewhere away from street  lights and other bright lights where you can see clearly to the north and east. head out early in the morning either just after midnight – although the Moon will make it harder to see some of the dimmer meteors o around about  3:30 to 5 a.m. toting a thermos of hot chocolate, tea or coffee. Make sure you’re suitably rugged up for the weather and get yourself all comfy in a reclining lawn chair, banana lounge or under a blanket or sleeping bag. No special equipment required.  Look towards the North and enjoy the beauty of the early morning sky and see how man meteors you can see.

The 2013 Partial Solar Eclipse is nearly here!

Posted on by

The morning of the 10th of May 2013 will see the Moon pass in front of the Sun in a rare event called an Annular  “Solar Eclipse”. The eclipse will start at sunrise in Western Australia; move over Northern Territory in the region of Tennant Creek and cross Cape York before heading out towards Papua New Guinea and the Pacific Ocean.  It will intersect the path of the total solar eclipse of 14 November 2012 in the area of the west coast of Cape York and will cross the east coast to the north of Cooktown. The indigenous communities of Kowanyama and Pormpuraaw will have the highly unusual privilege of experiencing two solar eclipses within six months. The rest of Australia will see a patial eclipse. The further south you go the less of the Sun there will be covered by the Moon.

eclipse

Figure 1: The dark strip in the centre indicates the best locations for viewing the eclipse. Here, the Moon moves centrally in front of the Sun. The eclipse is also visible in the areas that are shaded red, but less of the Sun’s disk is obscured. The fainter the red shading the less of the Sun’s disk is covered during the eclipse. Image from www.timeanddate.com

Here in Coonabarabran a partial eclipse will be in progress from 7:42am (AEST) until 10:16am with the maximum eclipse set for 8:53 am. This will be the only eclipse visible in Australia in 2013.

From Coonabarabran only about 35% of the Sun will be eclipsed by the Moon, giving it an appearance similar to a gibbous Moon. The Moon will move across the North- Western limb of the Sun during the Ingress phase, and will leave the Sun’s disc on the Eastern limb.

In 2014, on April 29 another partial solar eclipse of similar coverage will be visible as the Sun is setting with maximum coverage occurring just before sunset. So this is the last opportunity to see a reasonable partial eclipse from the area for a decade. In 2023, there will be a very small, with only 0.138 of the solar surface covered mid-afternoon and then we will need to wait for the total eclipse of July 22, 2028 for a really good view!

WARNING: Viewing the Sun is quite dangerous and proper precautions should be adhered to so that no damage to your eyes will occur, by far the safest method is to use “Pinhole Projection” where a small hole about 1mm in size is punched through a piece of stiff white card so that the Sun’s image will be projected on a card placed behind it. This is an indirect form of viewing the Sun during the phases of the eclipse.

It is advised that children be supervised by adults closely at all times and should not be left unattended.

DO NOT use dark sunglasses, tinted windows, smoked glass, dark film etc to directly observe the Sun as these materials do not filter out harmful UV and IR radiation which can damage your eyesight.

DO NOT use cameras or any other optical aid such as telescopes or binoculars which do not have FULL APERTURE SOLAR FILTERS fitted.

A safe method of directly observing the Sun with the unaided eye will be to use “Eclipse Shades”, which are made from a special black polymer designed for observing the Sun. They are designed to filter out 99.9999% of the Sun’s visible light as well as completely blocking harmful Ultraviolet and Infrared radiation from the Sun. This will allow comfortable and SAFE observing provided that you adhere to the warnings labelled on them.

Eclipse shades can be purchased from reputable suppliers of Astronomical products.

 

Tonights Lunar Eclipse

Posted on by

The November 28 penumbral eclipse of the moon will be the last eclipse of the year. People in Alaska, Hawaii, New Zealand, Australia, and most of Asia will be on the correct side of Earth to see the eclipse. The western U.S. and Canada will also catch part of it.

So Alaska, Hawaii, New Zealand, Australia, and east Asia will see the entire eclipse on November 28. For western Canada and the western U.S. moonset will happen sometime after mid-eclipse. For eastern Canada and the eastern U.S., the eclipse will begin after moonset. No eclipse on November 28 for you in the east … sorry.

Penumbral eclipse starts – 12:14:58 UTC – 23:14:58 AEDT
Greatest eclipse – 14:33:00 UTC – 01:33:00 AEDT
Penumbral eclipse ends – 16:51:02 UTC 03:51:02 AEDT

Visibility of penumbral lunar eclipse of November 28, 2012. Image Credit: Fred Espenak

At mid-eclipse, nearly the whole moon will be submerged in Earth’s light penumbral shadow. The exact eclipse magnitude is 0.9155 which means that the best time to look at this eclipse is about 30 minutes or so before and after mid-eclipse and look for a light grey shading.

The fact is that Earth’s shadow has two parts: a dark inner umbra and a lighter surrounding penumbra. It’s this lighter penumbral shadow of Earth that the moon will enter on November 28, 2012.

In 2013, there will be three lunar eclipses – a 27-minute partial on April 25, and two penumbrals.

Siding Spring Observatory Open Day – Saturday October 6, 2012

Posted on by

On Saturday October 6th, the Annual Siding Spring Open Day will be held here at Siding Spring Observatory. A number of the telescopes will be open during the day to the public.

There will be a BBQ lunch available; a shuttle bus on site to help you move around and see all there is to see. You will have the opportunity to talk to astronomers and learn about what science is carried out here.

Solar observing will also be available and there will be talks in the Exploratory lecture theatre throughout the day.

The Exploratory cafe will be opened for a well deserved cuppa, Devonshire tea or light lunch from the International menu. Visit the various telescopes and listen to astronomers talk about the research they do. Take part in the trivia treasure hunt to win prizes on the day.

Entry to the event is free. The Open Day will start at 10am and run until 4pm.

Science in the Pub – the End is Nigh! or is it?

Posted on by

Join for Coonabarabran’s Annual Science in the Pub

 This entertaining event starts the weekend off on Friday October 5th, 2012 from 6.30pm.  This annual debate is definitely entertaining and can be thoroughly outrageous at times as a group of astronomers from various backgrounds debate a topic of astronomical interest at the Royal Hotel, John Street Coonabarabran. This event has an entry fee of $5 and provides entry into the drawer for a variety of prizes on the night. Profits all go to a local charity. Food is available for sale on the night. Bookings would be appreciated. Vegetarian meals are also available. Enjoy Dr Fred Watson, Dr Amanda Bauer and Dr Bradley Schaeffer debate “The End is Nigh! Or is it?” and be a part of the fun in the Q&A!