The Cosmic River

Uranus at Opposition

2011-09-26T01:11:00.000+01:00

On September 27th (around 0059BST to be precise) the planet Uranus reached opposition. What's so important about that? Well the planets with orbits outside the Earth's orbit are all best seen when they're opposite the Sun. The following picture shows you why:

At opposition, a planet is near it's closest possible distance to Earth. In the night sky the planet is brighter than usual and through the telescope eyepiece - it is bigger than usual.

Uranus is on the opposite side of the sky to the Sun at present. That means it's visible from dusk 'til dawn for the weeks around opposition. This year you can find it against the backdrop of the constellation Pisces. Here's a Stellarium rendition of the eastern sky at about 11pm (as I write this blog post!)

You don't need a telescope to see this planet. Technically it's visible to the unaided eye (at magnitude +5.7) but it's easily visible with binoculars provided you know where to look. The easiest way for me to describe it is starting with an asterism of four stars called the "Square of Pegasus". Trace an imaginary line down from the two stars on the left side of this box by about the same amount and you'll be almost exactly in the right place. There aren't many stars in this part of the sky! Well away from the Milky Way, you're actually looking out of the Milky Way into the wider universe. A story for another day. A more detailed map of the sky shows the position of Uranus more clearly:

Uranus is slowly moving westwards (towards the right) each evening as the red track shows. Come to a NASTRO observing session if you need more help finding it.

The light from Uranus, which has travelled nearly 2.9 billion km, is very dim. A telescope reveals it to be a pale blue-green. Some magnification - upwards of 80x - shows it to be decidedly non-stellar - a tiny little planetary disk! Unfortunately bigger telescopes and higher magnification don't bring out any detail; no turbulent cloud systems like Jupiter and occasionally Saturn are to be seen here. This is view from Voyager 2, the only spacecraft to have visited the planet back in 1986. Nothing to see here!

Actually, more recent pictures from the Keck Observatory show that the atmosphere began to liven up as the equinox reached the planet

The moons of Uranus - the five largest anyway - are possible targets if you're observing from a very dark site with a telescope of 12 inches aperture or bigger. Refer to astronomy software like SkyTools or Stellarium if you want to identify them. But they are faint - ranging from 14th to 15th magnitude.

Some factoids about Uranus:

Discovered in 1781 by Sir William Herschel. This planet would have been called George's Star if Sir William had had his way (after his patron, George III). Fortunately the convention of going for Roman deity names eventually prevailed.
Disturbances in the path of Uranus after it was discovered led sparked a mathematical search for an unseen more remote planet. Eventually, the culprit, planet Neptune was found.
Uranus is 14 times more massive than Earth. It's classed as an ice giant (not a gas giant like Jupiter and Saturn) because it has large proportion of 'ices' like water, ammonia and methane inside it.
Uranus orbits the Sun with a period of about 84 years. I try not to think of this as being like a big clock hand, with the clock being the length of my life, but oh....it's diffuclt. I was born when Uranus was in Virgo. Now it's half way around the ecliptic in Pisces. Hope I'm still around to see it in Virgo again in 2057!
Uranus orbits the Sun tipped on it's side (almost). This means the poles of the planet are pointed towards the Sun every 42 years. Seasons last 21 years on Uranus.
Uranus has a dark system of rings, discovered in 1977 when the planet passed in front of a star and the light dimmed and brightened several times before and after the event.

Good luck with your search and clear skies!

Comet Garradd (August)

2011-08-27T14:55:00.001+01:00

Now that the moon is gone from the evening sky it's time to track down an brightening comet!

Comet 2009/P1 Garradd ideally placed for UK astronomers. At the end of August the comet is moving westwards through the constellation Sagitta (the Arrow) and into Vulpecula (the Fox). These constellations are are very high in the sky during late evenings at this time of the year. Here's a star chart show the motion of the comet over the next week or so. Note the american style month/day for the date:

For a few days centred on September 3rd, the comet will be right next to the Coathanger cluster (Collinder 399, or Brocchi's cluster) - that'll make a nice picture! Here's a picture of the cluster taken by Malcolm Robinson:

The comet is currently around 8th magnitude, which puts it within the light grasp of good binoculars from dark sites. Those of you with telescopes shouldn't have too many problems seeing the comet provided you can find it.

It doesn't matter too much if the weather doesn't cooperate during this week. Comet Garradd is going to be around for the rest of the year and it'll be brightest in February 2012, at which time it could be shining at around magnitude 5 or 6 - on the fringe of naked eye visibility.

Moonrise eclipse tomorrow

2011-06-14T19:58:00.000+01:00

The lunar eclipse on the 15th will be in progress as the moon rises (from the UK) – an intriguing sight in the bright evening twilight. In Northumberland moonrise occurs at the south east horizon at about 9.45pm – just as the sun is setting below the northeast horizon.

Ideally you should try and observe from somewhere with clear view of the southeast horizon because of how low the moon will be for the duration of the eclipse. Lots of places to choose from on the east coast; a sea horizon will be perfect.

In fact the dramatic ‘total’ part of the eclipse will be over just 15 minutes after moonrise. Any nearby buildings or trees will hide it from view! By just after 11pm the moon will look more-or-less full again but still low over the southern horizon.

There's talk on various websites about the possible effect of the recent eruption of a volcano in Chile; a lot of ash in the Earth's atmosphere may darken the southern portion of the lunar disk significantly. We will see!

NASTRO are planning to meet up towards the northern end of Druridge Bay around 9 - 9.15pm. All welcome to join us. Here's a map:

Druridge Bay Google Map

Here's a grab from SkyTools 3 giving eclipse data for Hauxley Nature Reserve. The negative altitude values for the first part of the eclipse signifying that the moon is below the horizon.

2011 Jun 15 18:23 Lunar Eclipse, Enter Penumbra, Sep=+01°31'35", Alt=-25°

2011 Jun 15 18:53 Lunar Eclipse, Penumbra First Visible, Sep=+01°15'37", Alt=-21°

2011 Jun 15 19:24 Lunar Eclipse, First Contact, Sep=+00°59'06", Alt=-17°

2011 Jun 15 20:23 Lunar Eclipse, Second Contact, Sep=+00°27'24", Alt=-10°

2011 Jun 15 21:13 Lunar Eclipse, Mid-eclipse, Sep=+00°05'17", Alt=-4°

2011 Jun 15 22:03 Lunar Eclipse, Third Contact, Sep=+00°27'31", Alt=1°

2011 Jun 15 23:03 Lunar Eclipse, Last Contact, Sep=+00°59'30", Alt=6°

2011 Jun 15 23:33 Lunar Eclipse, Penumbra Last Visible, Sep=+01°16'01", Alt=8°

2011 Jun 16 00:03 Lunar Eclipse, Exit Penumbra, Sep=+01°32'10", Alt=9°

Lunar eclipse next week

2011-06-10T14:38:00.000+01:00

The tail-end of a total lunar eclipse is potentially visible on the evening of June 15th. The moon will rise in the southeast whilst totally eclipsed. You can see from the map here that the best place to view it is from the middle of the Indian Ocean. Oh well...at least we get some of it from the UK.

I'm going to watch this from Druridge Bay.

More details to follow soon...

Late February Night Sky

2011-02-27T22:27:00.002Z

The planet Jupiter, which has been shining brilliantly in the evening sky since last autumn, slips behind the Sun this month. Before it goes, it will make a brief conjunction with the planet Mercury. Around March 14^th – 16^th, the two planets will be close together in the western sky about an hour after sunset. The pair will be briefly visible in the twilight low on the horizon before setting together soon after. Jupiter will be the brighter of the planets. I'll try to get a picture of them!

Here's a picture of Jupiter taken on February 27th in the evening twilight just before 7pm.

Later in the evening the planet Saturn rises in the eastern sky and is easily the brightest ‘star’ in that part of the sky. Telescopes will show the rings quite easily and even powerful binoculars will show Saturn to look like a flattened star!

The winter patterns of Orion, Taurus and Gemini are sinking into the western horizon during the early evening. The following picture shows Orion setting over Hauxley Nature Reserve and a bunch of Nastronomers!

They are being replaced in the southern part of the sky by the traditional spring patterns of Cancer, Leo and Virgo. The constellation Cancer, the Crab, is very dim collection of stars which is tricky to spot. The most obvious thing about the constellation is a mysterious misty patch of light and is larger in size than the full moon. It is has several names: the Beehive, Praesepe (‘manger’) or less romantically as M44. Binoculars show the misty object to be a star cluster – a scattering of hundreds of faint stars. The cluster was one of the first objects studied by Galileo with his new telescope.

The planet Saturn serves as a marker in the evening sky for the constellation Virgo, the maiden. Far beyond the stars of Virgo is a great collection of distant galaxies known as the Virgo Super Cluster. It is like a city of galaxies – centred around 50 million light years away – and our own Galaxy, the Milky Way is being dragged across the universe by gravity towards it. Pointing a telescope at this part of the sky will reveal many faint smudges; our own galaxy will look like this to astronomers living in those galaxies. We separated from those hypothetical astronomers not only by distance, but also time; we see the Virgo galaxies as they were just after the dinosaurs died out and mammals were taking over the planet.

The familiar 7-star pattern called the Plough is overhead during the evening at this time of the year. The second star from the end of the Plough’s ‘handle’ is called Mizar. If you’ve got good eyesight you’ll spot a faint companion star very close to Mizar; it goes by the name of Alcor. The pair is informally referred to as the ‘Horse and Rider’. Many ancient cultures used these stars as a primitive eye test! The ability to see these stars back in the 2nd century probably meant being handed a spear and sent to the front row of the Roman legion! The star at the end of the Plough’s handle is called Alkaid; the name of this star shares and origin with the name of the terrorist group Al-Qaeda (and a little pantomime hiss is always heard when I tell people this during sky tours at Hauxley!)

Absorption lines at last!

2011-01-19T23:11:00.000Z

I've been trying to crack this spectroscopy for a while now. I set the scope up outside the back door and spent some time aligning it.

Rather than spend £8 on a spacer to increase the distance between the SA100 and the DSI chip, I've dismantled a couple of my colour filters - carefully removing the glass - and used those instead. Plugging the whole thing into the Celestron NexStar 102 and sorting out some problems because of the new focus distance - I slewed the telescope around to Betelgeuse. Immediately I could see an improvement over last time!

The blazed first order spectrum showed some detail. I tried several other stars: Rigel, Aldebaran and Mintaka. I couldn't see any obvious lines on Rigel and Mintaka. I'll process them all tomorrow to see if I got anything.

I stretched the Betelgeuse line spectrum into a band:

and tried to identify the absorption features. This is what I think is on there:

The image on the chip still doesn't seem big enough. I'll try and figure that out when I'm less tired. Surely not more spacers needed - I'm using three already! After that I'll have to calibrate the system so that I can measure the wavelengths of absorption lines and identify them in a less haphazard way,

Another attempt at spectroscopy...

2011-01-16T19:15:00.000Z

It's been a few months I tried last so I had another attempt at getting some stellar spectra this evening with the Star Analyser 100. I connected the Meade DSI 2 to the laptop and the Celestron NexStar 102. This is all after a software upgrade from the previous version, which didn't like Windows 7 at all. Anyway, I got some images this time (in between 3 laptop crashes).

Here is Capella (a bright G-type star) and its blazed first order spectrum:

And here is Aldebaran (a K-type star):

Both were the result of stacking about 60 or 70 frames in Registax. No absorption bands visible but you can see subtle differences between the two spectra.

I need another spacer to increase the distance between the diffraction grating and the chip. This would result in a longer image of the spectrum and an increase in resolution. Also, it wasn't particularly easy to get good focus on this telescope.

It was interesting to try this on a smaller telescope (I used the 14 inch at Hauxley last time).

Gibbous moon picture

2011-01-16T11:02:00.000Z

Here's a picture of the moon taken last night (Jan 15th) at about 6.30pm - minutes before the last of NASTRO's Stargazing Live events.

The camera (and post-processing) has captured some of the subtle colour differences across the moon, particularly to the north of Copernicus crater. Full moon is on the way and it's getting very bright through the eyepiece of the 16 inch!

Star Gazing Live

2011-01-09T12:06:00.000Z

Crescent moon on the evening of the 2nd event.

A really hectic weekend of BBC Star Gazing Live events is over! The weather seemed to put a lot of people off the Friday star party, but the skies cleared on Saturday and about 50 people (including NASTRO members) turned up on Saturday evening.

I took the picture of the moon with my Nikon D80 through the Celestron NexStar 102 at about 5pm on January 8th.

A busy week coming up. I'm doing a presentation at the first NASTRO meeting of the year on Thursday (provisionally called "Astronomy in 2011") and then two more Star Gazing Live events at Druridge Bay Country Park next weekend.

Winter Stars

2011-01-05T23:17:00.000Z

First attempt at astro imaging with the Nikon D80. Opened the shutter for 30 seconds to get Orion, Canis Minor and Canis Major. Very light polluted just outside our back door in Morpeth! Taken at 11pm.

My eclipse

2011-01-04T17:02:00.000Z

The partial eclipse at around 8.45am at Druridge Bay, Northumberland.

Arrived at Druridge Bay at 8am. Got cold. Stared at clouds over the North Sea for an hour and half. Took occasional pictures of cloud. Sun appeared through a gap in cloud just over a minute after the eclipse had ended. Went home.

Visibility of the planets in 2011

2010-12-30T12:58:00.001Z

Click the image for a larger view. (m) Mercury, (V) Venus, (M) Mars, (J) Jupiter, (S) Saturn

The chart above shows the visibility of the naked-eye planets throughout 2011. You can use the chart to determine the best times of the year to view the planets. For example, Jupiter will be best seen around opposition at the end of October. Venus can be seen in the morning sky until the start of April, and in the evening sky from November.

It's very difficult to see the planets when they are close to the Sun (less than 15 degrees) but the angle of the ecliptic to the horizon can make it easier at certain times of the year. I took this into account when producing the chart - it is designed for astronomers at 55 degrees North (but is generally applicable to the UK). When the planets are within the yellow zone it will be very difficult to see them without optical aid.

Intersections of the planetary lines indicates a conjunction in ecliptic longitude (in other words, the planets will appear very close together in the sky). The conjunctions are numbered and the details are give in the following table:

Event	Date	N	S	Sep (°)	Constellation	Elongation (°)
1	Mar-16	Mercury	Jupiter	2°00^′	Pisces	16° E
2	Apr-19	Mercury	Mars	0°38^′	Pisces	16° W
3	May-01	Mars	Jupiter	0°22^′	Pisces	18° W
4	May-09	Venus	Mercury	1°27^′	Pisces	26° W
5	May-11	Jupiter	Mercury	2°03^′	Pisces	26° W
6	May-16	Venus	Mercury	1°24^′	Pisces	25° W
7	May-21	Mars	Mercury	2°09^′	Aries	23° W
8	May-23	Mars	Venus	1°00^′	Aries	23° W
9	Sep-30	Saturn	Venus	1°16^′	Virgo	12° E
10	Nov-08	Venus	Mercury	2°00^′	Scorpius/ Ophuichus	23° E

N and S indicate which planets are north and south. The angular separation is given in degrees and minutes. For comparison, the angular size of the moon is about 0°30^′

I haven't listed every conjunction on the chart - some occur very close to the Sun. You can see from the chart and table that there's going to be a great gathering of the planets in the morning sky during April and May but it will be very difficult for us in the UK to see it!

Finally, here's an example of how to read the chart. Let's look at September 1st. Follow a horizontal line to see where the planets are.

Mercury is visible in the morning sky close to greatest elongation in the constellation Leo, close to the border with Cancer. Jupiter is in the constellation Aries and best seen in the morning sky. Saturn can be seen for a short time after sunset in the evening sky. Venus is an evening sky object but too close to the Sun to be seen. Mars is visible in the morning sky shortly before sunrise in the constellation Gemini.

Easy!

The inspiration for this chart design comes from one of my astronomy books (I still have it) called Amateur Astronomer by Antonin Rukl.

Eclipse at Sunrise (Jan 4th)

2010-12-28T19:46:00.000Z

I rendered this image with Terragen, based on information from SkyTools 3.

At dawn on January 4th the sun will rise over the UK whilst partially eclipsed by the moon. The picture shows how the Sun will look over a clear horizon (the sea, for example) at 8:40am – just a few minutes after sunrise in the northeast of England.

Over the next hour, the moon will gradually uncover the solar disk. The Sun will have returned to its normal appearance after 9.35am.

SkyTools 3 shows the appearance of the Sun at maximum eclipse at 8.17am. The Sun is in the constellation Sagittarius. Maximum eclipse occurs nearly 20 minutes before sunrise in the northeast of England.

The circumstances of the eclipse are as follows. The altitude of the Sun is shown in brackets.

Eclipse begins 7.05am (-11 degrees)

Maximum eclipse 8.17am (-2 degrees)

Sunrise (@Hauxley) 8.36am ( 0 degrees)

Eclipse ends 9.35am ( 5 degrees)

The greatest eclipse magnitude is 0.654 for observers in Northumberland and it occurs at sunrise. (This number is the fraction of the solar diameter covered by the moon). It corresponds to 56% of the area of the solar disk being obscured by the moon.

It may be possible to view the eclipsed sun as it rises without any kind of optical aid; the atmosphere acting as a temporary filter. However, staring at the Sun is not recommended! The period when it is safe to observe without protection may be brief or non-existent! Permanent eye damage can result without any feeling of discomfort. The danger is that you begin observing without optical aid and you don't notice so much that the Sun is getting brighter as it gets higher in the sky because you feel like you're adapting to the change. Very dangerous.

If you have binoculars you may be able to project the sun’s image onto a flat surface. Alternatively, when the Sun brighter and higher in the sky, a simple pinhole in a sheet of paper will allow projection of a blurry image of the eclipsed sun. Not all telescopes are suitable for observing without some kind of filter. Check the instruction manual or risk melting internal components (I did this with my first telescope!) Some tips for observing solar eclipses here and here.

Northumberland Astronomical Society are planning to meet and observe the eclipse - filtered telescopes and eclipse glasses are likely to be available. Follow developments on their website or on Twitter.

The following animation shows the visibility of the eclipse worldwide.

Credit: PD-USGOV-NASA

The eclipse will be visible over parts of Europe, the Arabian peninsula, North Africa and Western Asia.

Here's a preview of the other eclipses of 2011....

Another solar eclipse will take place on June 1st but it begins just after sunset, so it won't be visible from the UK.

Two weeks after that, at full moon on June 15th, UK observers have the chance to see a total lunar eclipse which will be in full swing as the moon rises that evening.

Two weeks later, at new moon on July 1st, a partial solar eclipse of very small magnitude will be visible from the Southern Ocean close to mainland Antarctica. Because of the location and likely weather conditions (southern winter) it's possible that none of the 6.9 billion people on the planet will see this.

The final solar eclipse of 2011 takes place on November 25th. It's a partial eclipse and will be visible from Antarctica, parts of South Africa, New Zealand and Tasmania.

Towards the end of the year, on December 10th, UK observers get another chance to see part of another total lunar eclipse. On that occasion we'll see the rising moon leaving the Earth's shadow.

Finally, the next solar eclipse visible in the UK is on March 20th 2015. This will be the best solar eclipse for us in the UK since the total eclipse of 1999 (which was clouded out for many of us!)

Winter Meteors (The Quadrantid Shower on January 4th)

2010-12-27T20:27:00.003Z

The first meteor shower of 2011 are the Quadrantids. The shower is named after the discarded constellation Quadrans Muralis (the mural quadrant) whose stars were incorporated within the boundaries of neighbouring Hercules, Bootes and Draco when the the IAU reorganised the constellations in 1928.

The position of the radiant is shown on the star chart below; it is situated about one-third of way between the tail of the Plough and the star Vega.

The star chart shows the sky as seen from the latitude of Hauxley, Northumberland (a little over 55 degrees N) at 6.00am on January 4th. The radiant is almost overhead at this time and meteors will appear to radiate from this point, appearing anywhere in the sky.

Meteors (aka shooting stars) occur when grains of dust plough into the upper atmosphere at high speed and disintegrate harmlessly. The dusty trail encountered by the Earth during the first week of each January was laid down by an object called 2003EH1. This object probably began life as a comet, generating the dusty trails we encounter, but now seems to be inactive and has the outward appearance of an asteroid.

Typical meteors from this shower are relatively slow moving and enter the atmosphere at about 42km/s (94,000 mph). Like I said, relatively slow! The brighter meteors are sometimes strongly coloured (red or green). The shower is active from about January 1st to the 6th, but the peak of the shower is predicted to occur at midnight (0UT) on the 4th. The peak occurs whilst the radiant is fairly low near the eastern horizon. The ZHR of the peak is generally 100-120 per hour. Unlike many other meteor showers, the Quadrantid peak is generally very narrow (rates are much lower outside the 6-8 hour window centred on the maximum). As the night draws on and the radiant climbs higher in the sky then the number of meteors will probably be seen to increase regardless.

This year is a great opportunity to observe the Quadrantid shower. There is no interference from moonlight so the only restriction on the number of meteors seen will local light pollution and geography. In fact, the moon will actually rise whilst eclipsing the Sun as seen from the UK (more about this in the next post).

I think a lot of amateur astronomers probably overlook this shower because it tends to require more commitment! It is usually freezing cold and may require loss of sleep before a working day. It is one of the more consistent showers of the year and is worth looking out for this time.

Further details about this shower can be found here and here. Check out spaceweather.com as the shower gets underway from January 1st.

A winter morning eclipse

2010-12-21T08:05:00.000Z

In the end we stayed in Morpeth to observe the eclipse. It was crisp and clear at the start and the view through binoculars was unforgettable. Just a hint of orange along the left side as the shadow approached half way. You can really see the curvature of the Earth on the edge of the shadow! Within minutes it completely clouded over. Saw glimpses of the orange/brown of the shadow as totality approached.

A gap in the cloud opened up about 10 minutes into totality and we saw the dim orange eclipsed moon as it was dipping towards the houses across the road. We ended up watching from the bedroom window because the moon was so low in the sky. Well worth getting up for even if great British Weather did its best to get in the way. Absolutely freezing cold now though!

Solstice Lunar Eclipse (December 21st; morning)

2010-12-20T13:52:00.000Z

On Tuesday December 21st - the Winter Solstice in the northern hemisphere - a total lunar eclipse will be visible from an entire hemisphere of the Earth. Here in the UK, the eclipse begins as the moon is setting in the northwest. The full moon will be close to the junction of the constellations Taurus, Gemini and Orion.

Lunar eclipses occurring at moonset can be pretty spectacular; the orange/red of the eclipsed moon contrasts the brightening blue dawn sky directly opposite the Sun.

Because the Sun isn't a point source of light, the Earth's shadow has a dark central core (the umbra) and a diffuse boundary (the penumbra). Project the shadow of your hand onto a wall using a desk lamp and you'll see the same shadow components. The times at which the moon passes through the umbra and penumbra are listed below:

Moon enters penumbra: 5:29am

Moon enters umbra: 6:32am

Totality begins: 7:40am

Mid-eclipse: 8:18am

Totality ends: 8:55am

Moon leaves umbra: 10:03am

Moon leaves penumbra: 11:06am

It is very difficult for the casual observer to detect the penumbra; most people will not perceive the eclipse to have started until perhaps 6.15am. Once the moon has crossed into the umbra the moon will appear to undergo a steady change in appearance as totality approaches. These changes are shown in the animation below.

From Northumberland the eclipse will be visible until moonset at around 8.20am (varying by a few minutes across the region) so only the first half of this eclipse will be visible from the UK. A clear view of the northwest horizon is essential to view this eclipse!

The moon passes just north of the shadow axis.

The inner circle represents the extent of the umbra and the outer circle is the penumbra. The duration of totality (the period in which the moon is immersed in the umbra) is about 75 minutes.

There isn't anything intrinsically important about the eclipse taking place at the solstice (although astrologers will make something of it). A bit of research reveals that this is the first December solstice total lunar eclipse since December 21st 1638!

The moon turns orange/red (with perhaps hints of blue) because some of the sunlight is still able to reach the moon by being refracted through our atmosphere. The colour of the eclipsed moon is the sum of all the sunrises and sunsets taking place around the Earth during the eclipse. Astronomers are predicting that this will be a bright eclipse, because the stratosphere is mostly clear of volcanic dust.

Not sure yet where I'll be observing it from (or even if the weather will allow it) but I saw a spot about a mile north of Morpeth which should give me a decent view of it.

Snowbound astronomer

2010-12-05T20:29:00.000Z

Sooooo cold! Not much chance recently to do any astronomy because of the weather.

Anyway, a telescope was donated to the astronomy club recently and tonight has been my first opportunity to give it a try. As you can see conditions weren't ideal - freezing, icy and surrounded by light pollution. At least the sky was clear!

The telescope is a Celestron NexStar 102 SLT. It was very easy to assemble the mount and tube - just a few minutes from being boxed to getting ready to align it. The alignment was a breeze (after sorting out the date and time and remembering that this is an american bit of kit, so month-date not date-month!) A quick three star alignment was all that was needed and the telescope was able to comfortably slew to M57, Jupiter, Uranus and Vega - all pretty close to the centre of the eyepiece view. The view through the eyepiece (25mm) was crisp and clear given the observing location in Morpeth.

It'll certainly play an active part in our forthcoming outreach programme.

The Lunar X

2010-11-13T22:36:00.000Z

Just back from Hauxley after the clouds rolled in and stopped observing. I had the 14 inch aimed at the moon and was looking for some interesting craters to image on the terminator. A bright X-shaped feature jumped out at me! I've seen pictures of the so-called Lunar-X before but I hadn't seen it for real myself.

The Lunar-X is visible for a short period of time (only 4 hours or so) before first quarter moon. It is a shape formed by the walls of two overlapping craters catching the first rays of sunlight at dawn. The picture was taken with the Meade DSI 2, a focal reducer at 7.05pm on November 13th.

Before spotting the Lunar-X I was trying for some images of Jupiter. Through the eyepiece four moons were visible but the seeing wasn't great. I certainly couldn't see as much as the image here suggests (thankfully the wavelets can drag an awful lot of detail out!) I didn't have a Barlow lens to hand but I don't think it would have been much use tonight anyway.

So here is the only image of Jupiter I was able to get this evening, taken with the DSI2 at about 6.35pm.

Maybe it'll clear up in time for tomorrow...

Comet Hartley Closeup

2010-11-05T10:45:00.000Z

The EPOXI mission (formerly known as Deep Impact) made a flyby of Comet Hartley yesterday and sent back some stunning images of the cometary nucleus.

Comet Hartley remains visible to northern observers but it is now best seen in the morning sky. It is rapidly tracking south will soon be lost from Northumberland skies.

Lunar eclipse: the view from the moon

2010-10-21T22:29:00.000+01:00

I produced this with Terragen, Stellarium and GIMP. It a lunar eclipse as seen from the surface of the moon; from this vantage point the Earth eclipses the Sun - creating a ring of fire in the lunar sky. The landscape is bathed with the orange-red light of sunsets from around the world.

First foray into spectroscopy

2010-10-18T10:48:00.002+01:00

Another great night of observing at Hauxley on Saturday night. Emma, Malcolm, Dave H, Chris and his young son turned up on a clear evening. Highlights of the evening for me were getting some images of Jupiter which had a simultaneous Great Red Spot transit and shadow transit of Ganymede.

Here's an image of Jupiter, taken at 9.47pm and showing three moons, the Great Red Spot and shadow of Ganymede:

(This is more carefully processed version of the image from my previous post). The slightly comet shaped moons show that collimation of the 14 inch is not quite perfect.

Comet Hartley was reasonably easy with the binoculars, not far from Capella. Through the 14 inch I could see the central region of Comet Hartley as an oval smudge despite the moonlight. The Straight Wall on the moon (Rupes Recta) looked stunning through the 14” and Malcolm’s new eyepiece.

Later in the evening I got a chance to try my Star Analyser 100 and managed to obtain spectra from Vega, Jupiter, Aldebaran and Alcyone (brightest star in the Pleiades).

Here's the cropped image of Aldebaran and its blazed first order spectrum:

Stretching the image with GIMP reveals some dark features - absorption bands - in the spectrum.

There was a hint of an O2 line (slight darkening in the red part) and another between the green and blue (Titanium Oxide or Sodium?) but that was about it. It was very encouraging to get the system working at the observatory and produce something at least. I need another spacer between the SA100 and the CCD chip to increase the size (and resolution) of the spectra.

We stayed long enough to see the start of the shadow transit of Europa shortly after midnight.

Hopefully, many more nights of spectroscopy to come!

A good night at Hauxley

2010-10-17T01:20:00.000+01:00

Back from a hectic night of observing at Hauxley with Emma, Malcolm, Chris (and his son Jordan) and Dave H. Loads of images taken - I'll probably be image processing all day Sunday!

The picture above shows my image of Jupiter and some of its moons taken at 9.47pm with a rendition of the scene by SkyTools 3 at that time underneath.

More to follow...

Faint comet from Morpeth

2010-10-05T09:00:00.000+01:00

I know I can't do much astronomy from this part of Morpeth. Our house is surrounded by streetlamps and the neighbours still have loads of lights on at 9pm. Nevertheless I thought it would fairly easy to spot Comet Hartley with the 15x50 image stabilising bins.

I did eventually see the comet but it was with some difficulty and only after becoming as dark-adapted as possible in the darkest (not very dark) part of the garden. I really don't like suburban astronomy!

The comet appeared as a fairly wide diffuse patch of light and was just about in the same field of view as the star cluster NGC457 (The E.T. Cluster).

Hopefully there will be better opportunities to observe it with the 16" LB from Cragside on Saturday.

Comet Hartley brightens

2010-10-01T15:08:00.000+01:00

As the rain pours down outside it seems unlikely that I'll get to see anything astronomical tonight. Anyway, the waning moon and earlier sunsets mean that astronomy should be possible at a more sociable hour in the next couple of weeks.

Anyway, I've generated a chart for 103P/Hartley, aka Comet Hartley, the brightest comet in the sky at the current time. The chart above shows the motion of the comet over the next week. With the moon waning in the morning sky, the next couple of weeks will be a great time to go and look for this comet as it continues to approach maximum brightness later in the month.

Comet Hartley is in the prominent northern constellation Cassiopeia, whose pattern is marked out by a W-shaped formation of stars. From dark skies binoculars should show the comet as a diffuse but very obvious smudge of light. It is moving towards the constellation Perseus at a rate of about 2.5 degrees per day. The comet will pass close to the h and chi Persei, aka The Double Cluster, on the evenings of October 7th and 8th (closest approach occurs during daylight in the UK). This should be a fine sight from rural skies through binoculars and telescopes.

Psychedelic Saturn

2010-09-30T18:01:00.000+01:00

I love this false colour image of Saturn from Cassini! It's an infrared image with blue representing cooler regions and red/pink/purple as warmer regions. You can see the heat from the interior seeping through narrow bands around the disk. The green ring around the south pole are aurorae - southern lights! More detail here.

Here's a superb time-lapse movie of the northern lights on the planet:

You can follow the Cassini mission here.