Where the Sun hits the sky

2011 in review

philipstobbart — Tue, 10 Jan 2012 17:51:44 +0000

The WordPress.com stats helper monkeys prepared a 2011 annual report for this blog.

Here’s an excerpt:

The concert hall at the Sydney Opera House holds 2,700 people. This blog was viewed about 14,000 times in 2011. If it were a concert at Sydney Opera House, it would take about 5 sold-out performances for that many people to see it.

Click here to see the complete report.

Springtime for Spacetime

philipstobbart — Thu, 21 Apr 2011 19:11:35 +0000

Imagine you’re looking out onto a canal and see two insects on the surface of the water. Their weight presses down and causes a dip into which anything rolling on the surface could fall in towards them. This is how mass creates gravitational attraction by curving space-time – the bigger the insect, the larger the dip and the stronger the gravity. Now imagine the insects are moving about or spinning around. They can create small ripples on the water. Each ripple is like a small dip travelling out from the middle. Anything on the water’s surface the ripple passes under will be jiggled about, falling into the dips and pushed out by the peaks of the ripples. Space-time is a lot more rigid and the ripples a lot smaller, but it is that jiggling that missions like LISA are looking for.

Watching Saturn at Opposition

philipstobbart — Sun, 03 Apr 2011 13:31:55 +0000

The ringed planet Saturn is at opposition – ie it is at the part of its orbit that brings it closest to the Earth. This in turn makes it a good time to have a look at this most stunning planet.

Global Astronomy Month has also begun and they started things off with a live view of Saturn. For those wanting to look at how the professionals do it, Tom Stallard and Henrik Melin of Leicester University are presently stuck up Mauna Kea in Hawaii measuring the aurora with the Infrared Telescope Facility and have also put that online.

They’ve blogged about what they’re doing here and will be broadcasting 11am-5pm BST every day of their observations at this page.

Auroral blog on ROG Blog

philipstobbart — Sun, 17 Oct 2010 01:53:20 +0000

Max Alexander, the photographer behind the Explorers of the Universe exhibition has been featured in a blog entry for the Royal Observatory Greenwich site. The entry includes a photograph of two auroral filaments (paths taken by the impacting electrons) intertwined by the complex electromagnetic interactions of the involved currents. The entry signs off with an infrared image of Saturn’s aurora, featured in the ROG’s new planetarium show Meet the Neighbours.

The skies over Kendal in October

philipstobbart — Sun, 03 Oct 2010 00:38:18 +0000

We’re moving into the darker, colder and usually rather cloudy nights of the end of the year. As ever, this post is illustrated with a few sky charts showing midnight on the first, last and fifteenth day of the month. The dots represent brighter stars, green circles are star clusters, nebulae, galaxies and the like and the very brightest stars, the Moon and the planets are named when they appear. Sky charts provided using Stellarium.

Solar system

The Moon will be in the last quarter phase on the 1st, new on the 7th, first quarter on the 14th and full on the 23rd. On the 14th, the Moon will occult the star 50 Sagittarii at around 8:10pm for northern observers.

The middle of the month sees the start of the Orionid meteor shower, which will peak on the 21st. Peak rates are low and a full Moon will blot out all but the brightest. Orionids are fast and leave persistent trails. They are best seen before dawn.

Heavens above presently lists two comets above magnitude 12 and seven asteroids above magnitude 10 in the hours of darkness. The comets are: 103P Hartley at 5.6 – approaching visibility – in Cassiopeia and 10P Tempel 2 at 10.1 in Cetus. Details on the future movements and changing brightness of the comets can be found here. The asteroids are 6 Hebe at 7.8 in Cetus; 4 Vesta at 7.9 in Virgo; 8 Flora at 8.6 in Aquarius; 1 Ceres at 8.9 in Sagittarius; 7 Iris at 9.4 in Gemini; 39 Laetitia at 9.5 in Aquarius and 471 Papagena at 9.8 in Cetus – rather a busy constellation this month.

The Planets

Mars is usually lost in atmospheric haze now. It shines at +1.5, appearing in the south-west, only to set an hour after the Sun.

Venus is seen just below Mars as the Sun sets, shining much brighter, but also lower, requiring a very low horizon to the West to see it.

Mercury for the next day or two, Mercury is visible in the Eastern horizon shortly before the Sun rises, though it will appear dimmer than its +1.3 magnitude suggests due to the bright sky around it.

Saturn returns to the skies at the end of the month, making an appearance shortly before dawn with rings now angled such that they look more like rings. The planet will shine at a magnitude of 0.7.

Jupiter continues to shine brightly as ‘that star in the East’. It shines at a magnitude of -2.9 and is in an empty part of the sky. Its inclination is such that transits of satellites happen quite a bit. Times of some of these and appearances of the Great Red Spot are here.

Uranus lies a couple of degrees west of Jupiter, plus a little above, and shines at 5.7.

Neptune is also in the morning skies, on the border of Capricorn and Aquarius.

A few things outside the solar system

The constellations of Leo, Virgo and the Big Dipper are all home to galaxies, details here. This is not a good month to look at faint things as the all-night twilight obliterates detail and contrast.

The Usual Stuff

If you want to watch satellites flaring or passing in the sky (even sometimes during the day), then go to Heavens Above to get times and directions. If you need assistance in deciding where things are in the sky, why not install the free program Stellarium, which does all the work for you? Finally, to avoid the dreaded clouds, Met Check gives a quick forecast and the Met satellites or other satellites can be used to track breaks in the cloud. For an indication of auroral or solar activity, SpaceWeather.com is an invaluable resource. If the stars aren’t available, there’s always solar astronomy. Projections of the Sun onto white card can show sunspots, when properly focused. A good filter (not an eyepiece filter) or a dedicated solar telescope will show better details. Never observe the Sun without filters and never with an inadequate, inappropriate or old (and therefore possibly with holes in) filter.

Public events

For young astronomers (ages 9-16) Space Explorers is run in Kendal Museum on the third Saturday of most months from 2:30-4:00 pm. The next meeting is on Saturday the 23rd. The Society for Popular Astronomy also has a sky map for young astronomers here.

Plus why not pop along to the Eddington Society, which meets at Kendal Museum on the first Monday of each month, this month it is on the 4th, with member’s projects the subject of the meeting. There will also be a public observing event at The Brewery Arts Centre on the 15th from 6:30pm.

Don’t forget to check back here and on my twitter account for the latest astronomical events in this area.

FITS liberator now stand alone

philipstobbart — Sat, 02 Oct 2010 21:14:08 +0000

FITS Liberator is a thing that allows you to download, view and manipulate images in the complex FITS and PDS data formats, produce pretty pictures with them and render them in the simpler and more common jpeg and other image formats. Before now, it operated as an add on to Adobe Photoshop. Now, however, it has been released as a stand-alone free program.

Download it here.

What has ESO got hidden?

philipstobbart — Sat, 02 Oct 2010 20:30:38 +0000

The European Southern Observatory, which operates a number of high end observatories in the southern hemisphere, has put up a rather enticing webpage. It promises to open up and reveal ‘ESO’s hidden treasures’ on Monday, 4th of October.

We wait to see what they are…

Pan-STARRS spots hazard in space

philipstobbart — Sat, 02 Oct 2010 20:28:08 +0000

The Panoramic Survey Telescope and Rapid Response System, or Pan-STARRS 1, is a 1.8 metre telescope with a 1.4 gigapixel camera mounted on it, constantly surveying the sky. It hunts stars, galaxies and also anything that moves from moment to moment, specifically comets, trans-Neptunian objects and asteroids. Now it has managed to capture an asteroid that may or may not pose a future hazard.

2010 STS3 is a 45 metre wide asteroid, capable of causing regional disruption on a par with the object believed responsible for the Tunguska explosion, which flattened trees after a similar sized object exploded in the atmosphere above the sparsely inhabited region.

The object poses no immediate risk, but as it is passing close to us, it will be monitored and its orbital parameter derived from dedicated follow up observations to help determine more precisely where it will be. Presently, there is a small chance of an impact in 2098, but the margin of error on the orbital parameters is too high to make any warnings relevant.

The main significance of 2010 ST3 was that Pan-STARRS saw it first, proving its ability to detect these things when they appear. Pan-STARRS 1 is set to be supplemented by Pan-STARRS 4, a larger, more sensitive observatory, which will assist in surveying the skies.

Predicting the weather

philipstobbart — Sat, 02 Oct 2010 20:15:47 +0000

The BBC are running a series of comparisons and validations of various weather prediction services against one another in an effort to see if the Met Office is providing a sufficient service. It’s a semi public thing, with members of the public asked to send in their ideas of better weather prediction services and a public meeting planned for the 12th of October in London. Details here.

Vote for your favourate photowalk

philipstobbart — Sat, 02 Oct 2010 20:10:32 +0000

On the 7th of August, five particle physics institutions opened their doors to the public and their cameras. Each institution has chosen three of the resulting photographs taken on their premises and these fifteen pictures have gone to the public vote to decide which is the best. You have until the 8th of October to view them and vote here.