Gliding Along The Teapot’s Steam

Undoubtedly the mega topic in the media and water cooler these days are the remarkable images beamed back from Pluto. The mission started on January 19, 2006, with the launch of the New Horizon spacecraft. Weighing 478 kg and about the size of a baby grand piano, the stage was set for its nine and a half year flight. At a breakneck speed of 50,000 kph, it passed our moon in only nine hours compared to the Apollo days of a four-day flight. Thirteen months later it passed Jupiter and imaged the moon Io with a volcano in action. What was then the then ninth planet from the Sun was quickly demoted by the International Astronomical Union in a short seven months after liftoff to dwarf planet status. But no matter what category it falls in, its mission was a complete success. Although we have only seen a few images, the complete collection of data is slowly being sent back to Earth over the next nine months. Now New Horizons is now setting its sights on the Kuiper Belt. Who knows what mysteries will be revealed from Pluto and the Belt, populated by asteroids and short-period comets. The adventure has just begun.

As our summer sky darkens after sunset, cast your eyes to the southern horizon. The famous eight stars that make up the imaginary Teapot should be visible as it sits a few degrees about the horizon. These distant suns comprise a larger asterism of Sagittarius the Archer. To thoroughly enjoy the majesty of the night, check out this area from the countryside away from the dome of city light and any free-standing light sources. Also plan to be out when the moon will be absent as its glow will interfere. To accent, the Teapot, look west of the spout. What appears as steam rising from the pot is actually the glow of billions of stars too far to be seen individually. Our Milky Way Galaxy contains an estimated two hundred billion suns (200,000,000,000).

A good number of bright Messier objects can be found in Sagittarius and teamed up with the backdrop of the Milky Way’s glow (Teapot’s steam). Let’s begin with the spout of the teapot or the tip of the mythological arrow. The star is called Alnasl which comes from the Arabic meaning “the point”. It is a third magnitude orangey spectra class K1 giant and resides 96 light-years from us. Alnasl’s radius is twelve times that of our Sun and 64 times as luminous. In fact, if you take the distance between Kaus Media and Alnasl (three and a half degrees) and continue west by that same distance from the ‘point’ star, you are now looking at the galactic centre.

From Alnasl move six degrees north to M8. AKA the Lagoon Nebula is a vast star-forming region located 4,100 light-years away. This stellar nursery can be seen naked eye from dark regions so locating it should not be an issue. Even simple binoculars hold a treat to the eye. Along with its dusty nebulous regions, we see tiny inky black Bok globules, which are pockets of dense gas and dust that sometimes condense to form stars. East of this nebulous region you cannot help but notice NGC 6530, a cluster of very bright suns some 5,200 light-years away. At an estimated age of only 2.3 million years, these juvenile suns are young on the cosmic scale. A bit north and west of M8 (one and a third degrees) is M20. The Trifid Nebula located 5,200 light-years away is also a star-forming area. It is, however, more than that. The Trifid contains an open cluster, blue reflection nebula and dark nebula, dividing the target into three segments.

Continuing up the starry glow, you will come across the small open cluster M21 located 4,250 light-years and only holds about 50 stars. Keeping moving up until you come to a duo of open clusters namely NGC 6568 and NGC 6583. Nudging the scope another degree and a half Northeast and you will have the planetary nebula NGC 6578 in your sights, well barely as this is the ghostly remains of a once shining sun only measure 8.5 arc seconds across. We now end off the tour with two classic and star party favourites. First is M17 or commonly referred to as the Omega Nebula and is found four and a half degrees north of NGC 6578. Other names given to M17 are the Swan Nebula, Checkmark Nebula or the Horseshoe Nebula. Whichever way you like to call it, this gem of an object is an estimated 6,000 light-years away from us and is at the limit of naked-eye visibility or magnitude 6. This is a stellar nursery where stars are condensing gas and dust to grow in size. There is even an open cluster with a star embedded in this cloud of gas and dust. It appears to contain some 30 suns. The nebula itself contains hundreds of stars with hundreds more in the development stage.

And last but not least is the grand Eagle Nebula. Moving up two and a half degrees from the Omega, the Eagle is an awesome sight in the eyepiece. Although we are now moving in Serpens, M16 is located about 7,000 light-years away and is and same visibility as M17. The Hubble Space Telescope first imaged this object in 1995 and centred on what was called the Pillars of Creation.

Comet 67/P Churymov-Gerasimenko made a household name for itself as the Rosetta mission reached the distant comet and deployed the Philae lander to acquire first-hand information of the comet. Philae’s harpoons failed to anchor itself to the comet’s surface and unfortunately, the lander bounced a kilometre away and rested in the shadows of a canyon. But the news is not all bad as the comet’s orientation to the sun has changed and Philae has now been taken out of hibernation mode.  In the sky, 67P is moving east from Taurus but is still mag 13.5.

Considered as one of the best meteors of the year, the Perseids will peak on the night of August 12/13. About 100 meteors per hour will be burning up in the upper atmosphere at about 74 kilometres per second or a three of a second travel time between Ottawa and Montreal. With the new moon occurring on August 14, the glow of the moon will not be a burden this year.

As for the planets, Saturn is well placed for observing but is now setting after midnight local time on the first of the month and 10:30 on the 31st. Venus is in inferior conjunction on August 15 and too close and dangerous to been seen in the solar glare for most of the month. Do not take a chance in damaging your eyesight but it can be safely seen low in the east during the last week of August. On the morning of August 20, you will have to battle twilight as the red planet Mars passes through the Beehive cluster M44 with both a mere few degrees above the brightening horizon. The Full Sturgeon Moon occurs on the 29th at 14:35 eastern time. It is one of the closest perigees this year with large tides predicted for the 30th.

Until next month, clear skies everyone.

Gary Boyle

Twitter: @astroeducator

eNews date: 
Saturday, August 1, 2015