Northern HemisphereIan Morison tells us what we can see in the northern hemisphere night sky during July 2016.Highlights of the monthJuly - Still worth observing SaturnSaturn reached opposition on the 3rd of June, so is now low (at an elevation of ~ 20 degrees) in the west-southwest as darkness falls lying just over 6 degrees above the orange-red star Antares in Scorpius. Held steady, binoculars should enable you to see Saturn's brightest moon, Titan, at magnitude 8.2. A small telescope will show the rings with magnifications of x25 or more and one of 6-8 inches aperture with a magnification of ~x200 coupled with a night of good "seeing" (when the atmosphere is calm) will show Saturn and its beautiful ring system in its full glory.As Saturn rotates quickly with a day of just 10 and a half hours, its equator bulges slightly and so it appears a little "squashed". Like Jupiter, it does show belts but their colours are muted in comparison. July - Find the globular cluster in Hercules and spot the "Double-double" in Lyra There are two very nice objects to spot with binoculars high in the south-western sky well after dark this month. Two thirds of the way up the right hand side of the 4 stars that make up the "keystone" in the constellation Hercules is M13, the best globular cluster visible in the northern sky. Just to the left of the bright star Vega in Lyra is the multiple star system Epsilon Lyrae often called the double-double. With binoculars a binary star is seen but, when observed with a telescope, each of these two stars is revealed to be a double star - hence the name! Early July around midnight: look north to spot Noctilucent clouds. Noctilucent clouds, also known as polar mesospheric clouds, are most commonly seen in the deep twilight towards the north from our latitude. They are the highest clouds in the atmosphere at heights of around 80 km or 50 miles. Normally too faint to be seen, they are visible when illuminated by sunlight from below the northern horizon whilst the lower parts of the atmosphere are in shadow. They are not fully understood and are increasing in frequency, brightness and extent; some think that this might be due to climate change! So on a clear dark night as light is draining from the north western sky long after sunset take a look towards the north and you might just spot them!July 1st, 1 hour after sunset: Saturn and Mars make a triangle with Antares Around one hour after sunset on July 1st, given a clear sky and low southern horizon, you should be able to spot Saturn, above, and Mars, over to the right, or Antares in Scorpius. July 8th, 1 hour after sunset: A Waning Crescent Moon near Jupiter Around one hour after sunset on July 8th, given a clear sky and low western horizon, you should be able to spot Jupiter, above and to the left of a thin crescent Moon. July 16th after sunset: Venus and Mercury half a degree apartJuly 29th before dawn: A thin waning crescent Moon close to Aldebaran and the Hyades Cluster.July 30th after sunset: Mercury very close to Regulus in Leo.July 13th and 26th: Two Great Lunar CratersTwo great Lunar Craters: Tycho and CopernicusThese are great nights to observe two of the greatest craters on the Moon, Tycho and Copernicus, as the terminator is nearby. Tycho is towards the bottom of Moon in a densely cratered area called the Southern Lunar Highlands. It is a relatively young crater which is about 108 million years old. It is interesting in that it is thought to have been formed by the impact of one of the remnents of an asteroid that gave rise to the asteroid Baptistina. Another asteroid originating from the same breakup may well have caused the Chicxulub crater 65 million years ago. It has a diameter of 85 km and is nearly 5 km deep. At full Moon - seen in the image to the right - the rays of material that were ejected when it was formed can be see arcing across the surface. Copernicus is about 800 million years old and lies in the eastern Oceanus Procellarum beyond the end of the Apennine Mountains. It is 93 km wide and nearly 4 km deep and is a clasic "terraced" crater. Both can be seen with binoculars. Observe the International Space StationUse the link below to find when the space station will be visible in the next few days. In general, the space station can be seen either in the hour or so before dawn or the hour or so after sunset - this is because it is dark and yet the Sun is not too far below the horizon so that it can light up the space station. As the orbit only just gets up the the latitude of the UK it will usually be seen to the south, and is only visible for a minute or so at each sighting. Note that as it is in low-earth orbit the sighting details vary quite considerably across the UK. The NASA website linked to below gives details for several cities in the UK. (Across the world too for foreign visitors to this web page.)Note: I observed the ISS three times recently and was amazed as to how bright it has become.Find details of sighting possibilities from your location from: Location IndexSee where the space station is now: Current PositionThe Planets JupiterSeen low in the western sky after sunset, Jupiter is shining at magnitude -1.9 at the start of the month and has an angular diameter of 34.3 arc seconds. By month's end, these have reduced slightly to -1.7 magnitudes and 32.1 arc seconds. One hour after sunset it will be about 30 degrees above the horizon. Jupiter passes half a degree below the 4th magnitude star, Sigma Leonis on July 12th and continues to move eastwards, moving towards the Leo-Virgo boarder. Due to the low elevation, the atmosphere will limit our view somewhat but up to four of the Gallilean moons will be visible as well as the dark equatorial bands. The Great Red Spot will be harder to spot unless the seeing and transparency of the atmosphere are good. SaturnSaturn, having been in opposition on June 3rd, lies some 6 degrees north of Antares (in Scorpius) in southern Ophiuchus. It continues its retrograde motion westwards across the sky throughout July, narrowing its gap between Mars (now moving eastwards) from 19 degrees to 11 degrees as the month progresses. At the same time the brightness drops a little, from magnitude +0.1 to magnitude +0.3 whilst its apparent diameter falls from 18.2 to 17.6 arc seconds. Though only at an elevation of 20 degrees when due south at around 11 pm as July begins (and 9pm at month's end) the beautiful ring system, now at an inclination of 26 degrees is still worth observing as is Saturn's brightest Moon, Titan. MercuryMercury passes behind the Sun (Superior Conjunction) on July 6th, but may become visible in binoculars about mid month when it sets about 45 minutes after sunset as it lies just half a degree above Venus. During July's final week it will be seen to the upper left of Venus and moves closer to Regulus, in Leo, until the two close to just 22 arc minutes on the evening of July 30th. Mars VenusVenus, having passed behind the Sun on June 6th becomes visible in mid month low in the west-northwest shining at magnitude -3.9 in Gemini. It passes to the lower left of Pollux on the 13th andpasse through the Beehive Cluster, M44,in Cancer on the 20th, ending the month 5 degrees to the west of Regulus in Leo. Southern HemisphereHaritina Mogosanu from the Carter Observatory in New Zealand tells us about the southern hemisphere night sky during July 2016. My name is Haritina Mogosanu and tonight I am your starryteller from the Southern Hemisphere. In this jodcast episode I will talk about flying, since it is something I have always loved the most, besides the stars. This podcast is for Stephen who also likes flying. I always look up for planes and stars altogether, and I've always been happiest in the air. And many times I forget that whilst I am thinking that I am sitting still here on Earth yearning to be there in the skies, our planet is moving at an incredible speed. Moving but in relation to what? This is a good question. Well, to start with a point of reference, Earth is hurtling at 30 km per second around the Sun. We could measure these orbits in birthdays. One rotation, one birthday. So it takes Earth a year to go around the Sun once. The Sun also revolves around the Milky Way at 250 km per second. So that means that by the time we blink twice we already covered the distance from Wellington to Rotorua. Since our galaxy is larger than that, it takes roughly 230,000,000 Earth years to go around the Milky Way once... So one galactic year ago the trilobites were swimming in Earth's oceans... But that's not the fastest speed out there... According to Scientific American, the galaxies in our neighborhood are also rushing at about 1,000 kilometers per second towards a structure called the Great Attractor, a region of space roughly 150 million light-years (one light year is about nine and a half trillion kilometers) away from us. In terms of starry wings, there are many creatures out there among the asterisms imagined by humans. I will start with my absolute favourite object, which was discovered only a quarter of a century ago, the Milky Way Kiwi. July is the time when the centre of our galaxy, the Milky Way, is climbing all the way to the Zenith and from there, if there is a truly dark night, you can see the Milky Way Kiwi. Now you do need a very dark sky for that, and you need to know what you are looking for. Best you can see the Milky Way Kiwi in long exposed pictures of the night sky but I have seen it with the naked eye from Lake Tekapo Earth and Sky. Before I came to New Zealand, I had not known it existed, I've always thought that the dark patch I was looking at, if I was lucky enough to see it, was a dark horse. Suspended in the fabric of space, the center of our galaxy only rose about 30 degrees above the horizon, where I am from, near the 45 degrees North parallel. Besides, I did not even know what a kiwi bird was truly, let alone a celestial kiwi bird.Another favourite of mine is Cygnus the Swan. It's my home zenith constellation back in the Northern Hemisphere where it is also known as the Northern Cross. Cygnus is juxtaposed on the Milky Way. Very low on the Northern horizon here, it's main star Deneb is barely grazing the earth looking as if it's a slow moving flame that brazes the land with the galaxy. It rises one hour after midnight, as seen from Wellington New Zealand. A tad higher than Deneb, my favourite star, double star, - well actually triple, Albireo, is resolved in telescopes as one aqua blue and one orange star. That's a sight worth seeing at least every night when Albireo is in the sky. Cygnus rises around midnight. Aquila, the Eagle is another beautiful bird that flies in the Northern part of the sky, is low on the horizon rising, just after 8pm. Right at its tail, there is NGC 6751, a planetary nebula that looks just like an iris. Altair is the brightest star in Aquila and it's on the Milky Way. Opposite Deneb and Altair, on the south western part of the evening sky, Sirius is setting whilst Canopus is descending from heavens. In between Sirius, and Canopus, is the constellation Columba. The cat and the dog are chasing the Dove, which is what Columba means. For deep sky observing, near Phaet, the alpha star, brightest star from Columba, there is a beautiful spiral galaxy, NGC1808. Delicate and rich in optical double stars that we can seen with the naked eye, Grus the Crane is another bird-constellation laying now on the South Eastern Horizon. From Capricornus, that looks like a golf flag from here, hop two more blocks, passing another favourite star of mine, Fomalhaut, the loneliest star, in Piscis Austrinus and next stop south is Grus. I remember seeing Grus in a picture for the first time whilst Comet McNaught was here in New Zealand in 2006 and getting very excited about being able to recognise it by the multiple double stars in it. Since we are at the southern side of the sky, to be fair, as much as I don't like them, Musca, the Fly also qualifies for a flying creature. Near the southern cross, Musca looks like a patrulater. A small one, peering inside the coalsack. At the end of its abdomen, NGC4833 is a rather nice globular cluster. Near Musca, Apus, the bird of paradise's name literally means "no feet" in Greek, as it was once wrongly believed that the birds of paradise lack feet. Apus is pointing straight at Pavo the peacock, that is flaunting with feathers all over the south celestial circle. Next to Pavo, is Toucana, near the Small Magellanic Cloud (NGC 292). Some spectacular deep sky objects near it are the famous NGC104 also known as 47 Tucanae, but also NGC362, another globular cluster, NGC346 Open Cluster, NGC 290, open cluster and NGC265 Open Cluster. Toucana is neighbouring Grus on one side and the Phoenix, on the other side. Since Herodotus, the Greek historian, the bird of Phoenix was associated with the Sun, a phoenix obtains new life by arising from the ashes of its predecessor and it can live for 1400 years at the time. Inside the constellation, NGC55 is an irregular galaxy and NGC 300 is a spiral galaxy. The main star in Phoenix, Ankaa is almost halfway through Achernar and Fomalhaut. But a dark patch that looks just like a kiwibird, that is something that perhaps not too many people saw coming. Not too many people from New Zealand, I mean, because as i have discovered, being shown a kiwi bird, very few foreigners (I'm not counting the tourists here tho) can guess what that is. So the Milky Way Kiwi does carry all the weight of our stars. Not surprising, given what its equivalent on Earth, the kiwibird did. There is a beautiful Maori legend telling how the kiwibird lost its wings.
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