There's no trace of a tail in these pictures. That's just a consequence of the light pollution. When you see a copy of one of the raw images (left) used to make the above picture it's no real surprise that I'm struggling to find detail in the comet. Thanks Newcastle!
As usual I'm using IRIS to reduce the impact of that orange background.
Comet 2014 Q2 Lovejoy continues to head north towards the celestial equator. The view is improving every evening. Or at least it would if the moon wasn't around.
Here are a couple of pictures of Comet Lovejoy taken from my home in Red Row, Northumberland:
The picture on the left was a short exposure taken with my Nikon D80 on a fixed tripod looking towards the south. There's a lot of light pollution but the camera just about picks up the comet. It was easily visible with binoculars and I estimated the diameter of the coma to be about 20 arcminutes. The picture on the right was a stack of 9x60 second exposures. The images were centred on the comet and, since it's moving through space, the stars are trailed.
Moonlight is going to prevent me getting more pictures until after the first week of January. By that time Comet Lovejoy will be a lot higher in the sky and hopefully twice as bright as it is at the moment.
This is how the evening sky looks in January 2015. Click to embiggen!
The Moon and the hours of darkness
The best evening opportunities to have moonless sessions of astronomy come in the middle two weeks of January, after last quarter moon and until around the time of first quater.
Stars and constellations
Beneath the Belt stars is a compact group of stars known as Orion's Sword. Binoculars show this region has a large fuzzy region, which telescopes reveal to be a bright nebula --- the Orion Nebula. The other stars of the Sword are revealed to be star clusters rather than individual stars.
The whole region is superb to see with telescopes of any size.
The three prominent Belt stars, which make an almost perfect straight line, point upwards towards Taurus and the orange star Aldebaran, marking the eye of the Bull. Follow the line of the Belt stars down towards the horizon and you'll see the madly twinkling Sirius - the brightest star in the sky.
The Milky Way runs from northwest to southeast in the sky. Although this section of the Milky Way is less prominent than the part visible in the late summer and autumn in the UK, there are numerous star clusters and nebulae visible with binoculars and small telescopes as it flows through Auriga, Gemini and to the east of Orion and on to Canis Major in the south.
By contrast, the western part of the evening sky is fairly devoid of the bright stars. The autumn patterns of the Square of Pegasus, Pisces and Cetus mark a direction in which we can look out of the plane of the Milky Way, where there are fewer stars in that direction between us and the great voids between other galaxies.
In the east, particularly later in the evening, the galaxy filled constellations of Leo and Virgo are coming into view.
The first half of January sees a rare opportunity to spot three planets in the same part of the sky. Mars has been in the evening sky for months already but it is joined by Mercury and Venus which are both emerging from behind the Sun. Venus is the brightest of the three by far. Mars is the faintest and is distinguished by its strong orange colour. Look towards the western horizon in the middle two weeks of January to see all three together.
Meanwhile, on the other side of the sky the planet Jupiter shines brilliantly among the stars of Leo. It is far brighter than any star in the sky. Jupiter is nearly on the opposite side of the sky to the Sun and is visible for most of the night. Saturn can be found low in the southern sky before dawn shining as brightly as the brightest stars. Binoculars are sufficient to glimpse the ice giant planet Uranus in the constellation Pisces.
Related blog post and more details of 2014 Q2 Lovejoy here.
The annual Quadrantid meteor shower is active between December 28th and January 12th. The peak in 2015 comes on the evening of January 3rd, with the best time to observe being the early hours of January 4th. During the narrow peak rates as high as 120 meteors per hour might be possible. Unfortunately, an almost full moon will drown all but the brightest out of visibility.
The Quadrantid meteors radiate away from the border of the constellations Bootes and Hercules and it is named after a now defunct constellation – Quadrans Muralis - the Mural Quadrant.
The Cassini spacecraft captured this breathtaking view of Saturn on May 4th 2014 but I just noticed it today.
Cassini captured this view at a distance of approximately 2 million miles (3 million kilometers) from Saturn using a near infrared filter. Cassini was high above the ring plane and this is a view of the planet we never get from Earth. From our position near the centre of the solar system Saturn (and most of the planets beyond Earth) look fully illuminated all of the time.
One of the features that immediately catches the eye is that hexagon shape around the north pole of Saturn. The hexagon at Saturn's north pole isn't a new feature. It was seen in images taken by the Voyager 1 and 2 probes back in the 1980s.
Here are some closer Cassini views of it:
For some sense of scale: each side of the hexagon is a bit wider than the Earth.
Saturn is a rapidly rotating gas giant planet. How can a regular and seemingly long-lived feature like this arise in the atmosphere of Saturn? Astronomers don't have the definitive explanation yet although there is experimental evidence from laboratories on Earth which might give a clue.
The video shows an experiment to simulate conditions that might lead to a regular structure being set up in the atmosphere of Saturn. They built a cylindrical tank capable of varying the fluid flow within concentric regions inside. A hexagon appeared at the chaotic boundary between fluids moving at very different speeds. A number of vortices formed in the region separating the fluid flow and distributed themselves evenly around the pole at centre. Why a hexagon? Actually the experimenters could fine tune the spin rates to produce a hexagon but they could also generate other regular polygons too. You can see some them here.
The experiment showed how stability and order could arise from chaotic conditions induced by large differences in wind speeds at different latitudes on Saturn. There are still questions to be answered. For instance why is there no comparable feature at the south pole of Saturn? There is a huge, long-lived storm at the south pole, but no polygonal structure.
I love trawling through the raw image section of the Cassini website. It can lead to serious distraction no matter if they're images of the rings, the moons or Saturn itself. But I'm aware that this mission won't last forever; Cassini's time is running out and sometime in 2017 NASA scientists will place it in a final series of orbits which will send it crashing into Saturn.
Just bought a new Microsoft Surface 3. The (happy happy) days when I had to install the operating system myself are gone but I still have to put the software on.
Given that the resources are limited to 128GB (for the moment) on the tablet itself I can only really install stuff I absolutely need. So, this is a list of stuff that I can't get by without. Geek alert!
Absolutely must install SkyTools 3 too to record my observations at the telescope. I have installation disks but no CD drive so it'll have to wait for now.
I could happily survive without Microsoft Office but everyone else seems to use it. So therefore I have to. An unhappy situation. Space is tight on the tablet so I won't be installing Open Office alongside it.
Just put the finishing touches to a planetary elongation chart. Here it is in all of its glory:
A high quality PDF can be downloaded here.
This chart shows the positions of the naked-eye planets to the east (left) or west (right) of the Sun. The vertical axis represents the days and months of the year. The diagonal bands represent constellation boundaries. The wavy yellow band is a region close to the Sun in which it would be difficult to observe the planets. This chart behaves like a game of PacMan; any planets reaching opposition 180 degrees west of the Sun wrap straight over to the evening sky on the far left. Think of this as being like an unwrapped cylinder!
The places where the paths of the planets intersect represent conjunctions. These are visually striking opportunities to see bright planets shining together in the sky. In 2015 there are at least 12 such opportunities.
There's a particularly striking gathering of the planets in the morning sky during October 2015. The planets Mercury, Venus, Mars and Jupiter will all appear together before sunrise on many of those autumn mornings.
Here's a star chart showing the northwards drift of the comet during the first weeks of 2015.
I've left the magnitude estimates off the chart but astronomers are expecting Comet Lovejoy to be around 6th, maybe even 5th magnitude during this period. That will put it within easy reach of binoculars and small telescopes. From especially dark sites it might attain naked eye visibility.
Comet Lovejoy is very well placed for UK astronomers in the New Year. After beginning the month close to the southern horizon in the early evening sky it rapidly climbs north from Lepus (the Hare) through Eridanus (the River) and into Taurus (the Bull).
Just a bit of background on the comet itself. It was discovered by veteran comet hunter Terry Lovejoy in August 2014 and was his 5th comet discovery. This one is going to reach a similar brightness to one of his previous comets - 2013 R1 - which was visible in the UK in late Autumn 2013.
2014 Q2 Lovejoy will be closest to Earth (0.469 AU / 43.6 million miles) on January 7th. It will reach a perihelion (closest to the Sun) distance of 1.29 AU (119.9 million miles) on January 30th. The entire orbit of this comet lies outside Earth's orbit and that's why the comet can be seen almost on the opposite side of the sky to the Sun despite being near perihelion.
I'll post updates on Comet 2014 Q2 Lovejoy and, hopefully, some pictures over the coming weeks.
A PDF finder chart is available here.
I've been spying the Intergalactic Wanderer recently through the telescope. That's a much more poetic name than NGC 2419, which how astronomers officially catalogue it.
I took a picture of it last year with my usual setup: Nikon D80 at prime focus of a Celestron 4 inch refractor.
That fuzzy ball at the centre is one of the Milky Way's largest, most massive globular clusters. It contains twice as many stars as Omega Centauri and perhaps five times the number of stars found in the "Great" Hercules Globular Cluster, M13. In other words - the Wanderer is huge. Only its vast distance makes it look unimpressive through small telescopes.
Here's a clearer picture of it.
The Intergalactic Wanderer is about 300,000 light-years away. That's almost twice the distance of the Large Magellanic Cloud (the largest satellite galaxy of the Milky Way). In fact the "Wanderer" title was conferred when astronomers though the cluster might not be part of the Milky Way. Now, astronomers realise that the Wanderer does indeed orbit the centre of the Milky Way but it takes around 3 billion years to do so.
Despite it's relative obscurity - even amongst amateur astronomers - this faint fuzzy has gained some degree of recognition through its appearance on a frequently shared Facebook meme:
...which probably has more than a grain of truth in it.
It's mostly work, work, work with a dash of astronomy. I'm writing end of semester exams for the two maths modules I teach. I'm fine tuning some booklets of maths practice problems for the students to take away over the Christmas period. I spent a few hours last weekend writing an online test for Monday morning...but the computers all crashed when the students came to do it. So I'm hastily writing a replacement to do next Monday instead. On top of that I'm fixing some explanations and problems in the previous version of my maths book; there are a lot of things I need to improve about the textbook since I started teaching some of the topics - like Functions - this year. On Friday I've got an astronomy event with NASTRO at Bamburgh. Not sure what I'm going to talk about at that. Lots of young astronomers expected so I want it to be interactive. Over and out :-)
Dr Adrian Jannetta
Guitar strummin' explorer of the universe. Mild mannered maths teacher by day and astronomer by night.