Podcaster: Ralph & Paul
Title : Awesome Astronomy – July Sky Guide for Northern Hemisphere
Organization: Awesome Astronomy
Link : www.awesomeastronomy.com
Description: What to look out, and up, for in July: safely observing the sun at its closest point to Earth, a tour of the planets visible with the naked eye and with telescopes this month, our closest neighbour – the moon, the wonderful telescope and binocular objects towards the galactic core and the meteor showers on offer this summer.
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 fact-based but frivolous.
Transcript:
Well, summer’s the perfect time to get out there and look at our nearest star, of course taking all the necessary precautions, never look directly at the Sun and always get advice before you attempt any observations. If you have been looking at the sun regularly this year you may notice that we are now at aphelion, which occurs on the 5th July, where Earth is at the furthest point from the sun on its orbit, this will mean the sun appears slightly smaller in the eyepiece than it did back in January at perihelion, I think Northern Hemisphere observers often find this a bit counter intuitive as the Sun is further away in their summer and closer in winter, the difference is only 10.42 Million Kilometres, which is not a great amount compared to the average distance of 146.9 million kilometres, it makes some difference to the amount of energy arriving at Earth, but it’s not dramatic. Hopefully, despite it’s greater distance, you can all enjoy a bit of Sun over July even if it’s just of the relaxing in a garden chair variety of sun observation.
So on to the planets. We’re working our way out of the drought as time goes on and if you’re an early riser then the sky is improving for planetary watchers. If you were fortunate enough to catch the triple conjunction at the end of May (and that was pretty spectacular) then there is a repeat before dawn from the middle of the month with Mars filling in for Venus, in the company of the remerging Jupiter and Mercury. All three will be sitting in the constellation Gemini which will rise around 4 am and if you start looking to the North East around this time from the middle of the month you should hopefully start picking them up, with Jupiter and Mars rising first. You’ll have less then an hour to observe this before sunrise, though this will improve as the month progresses. 25th July onwards looks to be the best period to observe this. If its anything like the Jupiter Venus Mercury event at the end of May then this is definitely worth the early morning, or pulling that all nighter.
Moving further afield onto the ice giants, Uranus and Neptune. We should be getting good and ever improving views of these two throughout July, with Neptune sitting in Aquarius and approaching opposition next month, while Uranus is following behind in Pisces. Now of course unless you have a very large aperture you are not going to see much except a small blue/green/grey disc, but don’t let you put this off having a look. We are talking about two mysterious and barely explored worlds at the further reaches of the solar system and that has got to be worth a look. By the end of the month both Neptune and Uranus will have risen before midnight for most of the northern hemisphere so we’re soon approaching the point where they will be evening objects.
At more sociable hours we still have Saturn in the evening sky and despite being well past its best and approaching the evening glare of the setting sun it is still always worth a look, the rings have been well presented this apparition, so do enjoy your last good views before we lose out to the Sun.
Then there’s Venus that will be a pretty dominating sight in the evening sky, blazing away at Mag -3.8 in Cancer. It’ll be presenting between a 90 and 80% phase though the month and with colour filters you should hopefully be able to pick out some cloud detail.
Of course what this means is that in the last week of July if the weather is kind we have a window of opportunity to view all seven planets over one night, a good challenge for imagers and observers alike.
The moon, always worth an observing session, presents European observers with two nice bright star occultations. Occultations occur when the moon moves in front of a star or planet and is a surprisingly rare event, the moon being a much smaller object than most people think. This month there are actually six bright star occultations, with two visible in the UK and western Europe first we have an occultation of star Epsilon Tauri on the 5th July at 3am BST, 2am UT and then on the 19th July the moon occults Beta Scorpii, also known as Graffias, at half past midnight BST, half past eleven on the 18th in UT. Depending on your location you will see either a full occultation where the star disappears and reappears, a grazing occultation where the star appears to brush the edge of the moon or you’ll see a near miss. Do look up online for more information, we’ll place links on the Awesome Astronomy FB group and remember to set up in plenty of time to view as the timings of these events are still quite imprecise.
Moving on to deep-sky objects it’s the view of the southern sky that should hold your attention in July as it’s the time of year where many Northern Hemisphere observers get a to have a little peak of the delights of the southern hemisphere. Sitting on the southern horizon will be the constellation of Sagittarius with the famous teapot asterism and it’s famous nebulosity like steam rising from the spout, which is of course the Lagoon Nebula, the large and small Sagittarius star clouds and of course the Galactic Centre. Here is the milky way at its densest and for collectors of messier objects the low southern sky in July presents you with an opportunity to see 22 of them close together, Nebulas M8, 16, 17 and 20. Open clusters 6, 7, 11, 26, 18, 21, 23, 24, 25. And Globular clusters, 4, 10, 12, 19, 22, 54, 55, 62, and the bous ball 70!
This is also a great area for binocular astronomy, which I think many telescope owners tend to forget about, which is shame as some objects and areas of the sky make for incredible views in a pair, sometimes a better view than the narrow close up available in a telescope. M24 for instance is considered one of the most dense and spectacular star fields you can view and is in many respects a better binocular object than telescope. Certainly Globular cluster M22 is well worth a look in both binoculars and telescope as it is the biggest globular cluster that can be seen from the Northern Hemisphere, not as many imagine M13.
So find yourself a good clear southern horizon view and take in the galactic centre and it’s neighbourhood this month
Last in this month’s skyguide are the meteors. We have a few showers in July, but mostly quite weak with low zenithal rates. The Capricornid shower has three peaks, the first on the 8th, the second on the 15th and the last on the 26th while the Delta Aquarids peak on the 30th. The capricornids are an interesting shower as its parent body was at first identified as an asteroid -2002 EX12 but subsequently this body was established to be a comet now called 169P/NEAT. Of further interest is that although this shower is a weak one of bright, slow moving meteors, the bulk of material from the comet is not set to be in Earth’s way until the 24th century, by which time it may be one of the great, high rate meteor storms. But of course here in 2013 avid meteor fans will be looking forward to our own high rate Perseids which begin this month on the 23rd, with the peak occurring on 12th August.
Of course any images, sketches or observation reports of anything in this guide and anything we haven’t mentioned we would love to hear about on our facebook group, via twitter and on our Flickr group.
End of podcast:
365 Days of Astronomy
=====================
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