Podcaster: Ralph & Paul
Title : Awesome Astronomy’s August Sky Guide
Organization: Awesome Astronomy
Link : www.awesomeastronomy.com
Description: What to look out, and up, for in August: the magnificent Perseid meteor show comes to town, we tour the planets visible with the naked eye and with telescopes this month, give you our pick of the moon’s craters and the deep sky objects on offer inside the Summer Triangle
Bio: Awesome Astronomy is the show for anyone and everyone who has even the slightest interest in astronomy and science.
Join Ralph & Paul at the beginning of each month, for an informative and fun astronomy programme telling you what to look out (and up) for every month. You can be guaranteed a passion for astronomy, simple explanations of complex and fundamental topics, space and science news, absorbing interviews and listeners’ astronomy questions answered.
As both presenters have been accused of being a little skeptical in the past, you can also expect everything to be frivolous but fact-based
Transcript:
Lets start with probably the highlight of summer astronomy, the Perseid meteor shower. There are many good showers through the year but the combination of warm summer evenings, the length of the shower and potential zenithal rates that can approach 100 an hour make the perseids unmissable. The peak of the shower will occur between 1845 and 2045 UT on 12th August, which for the UK is still in twilight as Sun set is not until 2045. But as darkness falls and the sky over the UK turns face on to the debris stream of Comet Swift-Tutle the shower should still be spectacular. The Perseids are a long shower, beginning on 15th July and not ending until 25th August so the nights leading up to the peak and the nights after are well worth watching too and with the moon still in its early phases the skies should be dark. The best advice for viewing is get a comfy seat, preferably something that reclines or a lounger, find a spot with as much sky as possible, any direction is good though east and south might be a good place to start. The so called radiant, the point of the sky where the meteors appear to originate from moves from the area of sky between Cassiopeia and Andromeda, past the double cluster into Perseus and Camelopardalis, at peak the radiant sits between the last two constellations. The Perseids are famous for high zenithal hourly rates, which is the number of meteors should conditions be ideal at zenith. Realistically we are probably looking at around 30 an hour which is still a great sight and worth spending a few hours enjoying on a warm summers night.
Moving onto the planets we are still in a position at the beginning of the month to see all seven planets, with views of Mars, Jupiter, Uranus and Neptune steadily improving though the month. Neptune reaches opposition on 27th August and will offer the best views of that planet for this year. It will be low down in Aquarius, about 2 degrees west of star Sigma Aquarii. This is a planet that despite being over 15 times larger than Earth and even at it’s closest will be 4305900000 kilometres away and is still a tiny object and will need binoculars or telescope to be seen. Small scopes will see a small dim blue/grey disc while larger scopes may well pick up the largest moon Triton, which has the unique distinction in the Solar System of being a retrograde orbiting moon.
Uranus is following behind in the constellation of Pisces and is has still a way to go before its best with opposition due at the beginning of October. In a good sky Uranus is a naked eye object though at present with summer skies and low altitude will need to be very good.
Mars and Jupiter begin the month as they ended July rising together before dawn in Gemini and for the first part of the month they are followed by Mercury. With the Sun rising just after 5am BST, 4am UT then the observation period is still quite short for this conjunction, but views of both Jupiter and Mars improve through the month, though both will appear quite small as neither is near opposition and in fact both planets will not reach opposition until 2014. Mercury will present a good size in the first few days of August, appearing 7 arcseconds, however it reaches its furthest from the Sun on August and then begins to move away from the other two and back towards the Sun.
Venus is very apparent in the evening sky and continues to move away from the Sun, currently it can be found in the constellation of, but is easy to find before any stars appear as it is sitting degrees above the sunset in the UK blazing away at mag-3.8. It is presenting a broad phase as the month progresses, Venus will not reach great hights this month but will be still worth a look..
Saturn is on borrowed time in August and it is soon going to be lost to the Suns glare, though it doesn’t officially reach Solar conjunction, where it passes behind the Sun from Earth’s perspective, until November, so this is the long goodbye and fans of the ring-world should grab their last views this month to see them through the Saturn free autumn and early winter.
This month’s moon is well timed for the persides and should be out of the way for the best of the shower. We start the month with a day old moon following full moon on July, while new moon is reached on August. Plenty to see on our satellite and with the short light nights still curtailing serious deep sky observing it is still a good time have a look at some of the fascinating objects the moon presents us. Look out for craters such as copernicus around the 15th, kepler around the 17th and Aristachus around the 17th-18th There are three good libration targets at the end of the month with craters scott, wexler and Lyot visible on the 19th, 20th and 21st respectively. These are down on the limb of the South East Quadrant and appear due to the phenomenon of libration where due to the moons eliptical orbit we get to see more than 50% of the moon surface.
Deep sky astronomy is still fighting its way out of the summer glare through august but the nights are lengthening and the skies getting darker. August has to be a good month for the Summer triangle, an asterism made of three stars – Deneb in Cygnus, Vega in Lyra and Altair in Aquilla and includes within it velpecula and sagitta. This is a rich part of the sky with the milkyway running through it and there are some great targets to hunt down with of course M57 ring nebula and M27 Dumbell nebula being two of the best along with NGC 7000 the North America Nebula. Also worth finding are globular clusters M56 and 71 as well as some of the overlooked open clusters like M39 and of course the famous coloured double of Alberio is always worth a look.
Ophichus an often overlooked constellation and one that in polluted skies is easy to miss, sitting below Hercules and to the right of the summer triangle it is home to a fantastic set of globular clusters, M10 and M12 can be seen in the same wide angle and picked up in binoculars, while M9, M14, M19 and M107 are scattered around waiting to be found. There is also the a spectacular imaging target in the Rho Ophiuchi complex, a beautiful patch of nebulosity on the southern edge of the constellation near Antares.
So lets hope for the kinds of skies we have had in July and do share any images, sketches or observation with us on our FB group.
End of podcast:
365 Days of Astronomy
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The 365 Days of Astronomy Podcast is produced by the New Media Working Group of the International Year of Astronomy 2009. Audio post-production by Preston Gibson. Bandwidth donated by libsyn.com and wizzard media. Web design by Clockwork Active Media Systems. You may reproduce and distribute this audio for non-commercial purposes. Please consider supporting the podcast with a few dollars (or Euros!). Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org. In the new year the 365 Days of Astronomy project will be something different than before….Until then…goodbye