Don’t forget to change your clocks this weekend! At 1.00 am GMT (2.00 am BST) on Sunday 25 March 2012, clocks go forward one hour as civil time changes from Coordinated Universal Time (effectively the same as Greenwich Mean Time) to British Summer Time or BST.
Unfortunately this also means that we all get a one-hour shorter weekend, but at least we get it back in October when the clocks change again.
Find out more in our British Summer Time fact file.
1 April 2011 – In the early hours of this morning, top ROG astronomer Firla Pool made a chance discovery while observing that could potentially reshape our understanding of alien life.
Making observations late into the night at the ROG’s famous 17¾-inch telescope, Ms Pool stopped by the astronomers’ refrigerator for a sustaining snack. On opening the door, she was amazed to be met by an array of colourful, pulsating lifeforms which had apparently evolved super-rapidly on an abandoned pot of pro-biotic yogurt, several years over its use-by date. Ms Pool was convinced that the lifeforms were trying to communicate with her, and claims she distinctly heard a voice saying “Take me to your larder”, though she later admitted that she may have been mistaken as she was rather tired.
Unfortunately, when an excited team of scientists and journalists arrived at the Observatory this morning, they discovered that the cleaner had got there first and had decontaminated the whole area. “I don’t know when that fridge was last cleaned,” confessed the cleaner, Miss Tayke. “We tend to avoid it as the astronomers keep Moon cheese in there, and it can get very smelly.”
Coincidentally, a member of the cleaning team was also involved in a surprise astronomical discovery on exactly the same date last year.
It’s that time of year again when residents of the UK lose an hour’s sleep in exchange for lighter evenings.
At 1.00 am GMT (2.00 am BST) on Sunday 27 March 2011 clocks go forward one hour as civil time changes from Coordinated Universal Time (almost the same as Greenwich Mean Time) to British Summer Time (BST).
The Ninth European Parliament and Council Directive on Summer Time
Arrangements states that summer (or daylight saving) time will be kept
between the last Sunday in March to the last Sunday in October, and the
changes will take place at 01.00 GMT.
Find out more about British Summer Time.
230 years ago today the size of the solar system doubled. Slightly before midnight on 13 March 1781, in his back garden in Bath, German-born musician and astronomer William Herschel clocked a strange object in the eyepiece of his home-made telescope. The curio, which Herschel initially thought might be a comet, would go on to be confirmed as a seventh planet, encircling the Sun at twice the distance of Saturn. Later named Uranus, it was the first new planet discovered since antiquity. However, things could have been very different if
John Flamsteed, the first Astronomer Royal, had known what he was looking at almost a century earlier.
A montage of Voyager 2 pictures of Uranus (the blue planet in the centre) and its largest moons. © Voyager 2
In 1675 King Charles II made Flamsteed the first incumbent of the post of Astronomer Royal at the new Royal Observatory
built on Greenwich hill by Christopher Wren. His task was simple: to accurately chart the heavens so as to contribute to a solution to
“The Longitude Problem” and save deaths from shipwrecks (or, perhaps more accurately, to stop the King’s treasure finding a new home at the bottom of the ocean).
By 1690
Flamsteed’s growing catalogue of “fixed stars” included the rather innocuously titled 34 Tauri, a faint object on the cusp of human eyesight in the constellation of Taurus. 34 Tauri would again be observed by Flamsteed in 1712 and 1715 and by one of Flamsteed’s successors as Astronomer Royal,
James Bradley, in 1748, 1750 and 1753. The trouble was that no-one realised they were looking at the same thing; the ‘fixed’ star had wandered across the heavens, the distinct calling card of a planet (from the Greek for ‘wanderer’).
It took the great resolving power of Herschel’s newly built 6.2 inch reflecting telescope to see 34 Tauri, which by 1781 had wandered into the constellation of Gemini, as a disc rather than a point like star. In fact, Herschel’s telescope was better than any at the disposal of Nevil Maskleyne, the latest Astronomer Royal and
the oft, and perhaps wrongly, maligned adversary of clockmaker John Harrison.
The collective Astronomers Royal may have missed out on the greatest astronomical discovery since the days of Galileo but Maskleyne, in backing Herschel, would play a crucial role in getting his German colleague’s discovery ratified. Maskleyne, a highly connected man at the head of English astronomy, called upon his European counterparts to further examine Herschel’s sighting. Calculations of its near circular orbit, rather than the highly elliptical orbit of a comet, and the lack of a distinct tail, confirmed that Herschel had nudged up the population of the solar system by one.
It was also Maskleyne who pressed Herschel to name the solar system’s latest inhabitant. Obligingly, Herschel first called it Georgium Sidus (or “George’s Star”) after the then King – but not yet mad – George III. However, arguments about the name persisted, not least because it wasn’t a star. In the end Uranus was adopted, being the father of Saturn, as Saturn was in turn the father of Jupiter in
Roman mythology.Finally, one of the greatest discoveries in astronomy to that time was officially acknowledged.. Overlooked by Flamsteed and Bradley, discovered by Herschel and brought to the forefront by Maskleyne, it would be another 65 years before Uranus would be usurped as the gatekeeper to the edge of the Solar System.
Colin Stuart is a freelance astronomy writer as well as presenter in the Peter Harrison Planetarium.
From 8 March 2011, the Royal Observatory, Greenwich will be introducing charges for part of its site. Admission will be charged for the Meridian Line courtyard (and the courtyard buildings). The Astronomy Centre with its three interactive galleries will remain free.
An adult ticket will cost £10. Tickets for concessions will cost £7.50. Children of 15 and under will be free. In each case, tickets will also be an annual pass so that local and UK visitors in particular will be able to visit as many times as they like during the year for no additional charge.
Since moving to free entry in 2001, visitor numbers have increased to 1.58 million. A great success story, but also substantially increases wear and tear on the site and the Museum needs to ensure that it has the resources to manage this increase in visitors safely, while improving their experience and maintaining the world-famous site and displays at the Observatory. The Museum is also involved in ongoing developments to update all of its galleries and facilities over a ten year period after a prolonged period of limited investment in these areas and needs to look at generating more of its own revenue to enable this work to progress.
A full breakdown of the
charges are available on our website here.
Last year the European Southern Observatory (ESO) decided to open its vast archives of astronomical data to amateur astronomers to see if they could find any hidden treasures. Terabytes of data spanning many years, instruments and technologies were made available. Anyone willing to put in the extensive time and effort required to process the raw grey-scale data to produce new images could enter ESO’s Hidden Treasurers 2010 astrophotography competition. The amazing winning images and all those submitted throughout the competition can be found in the competition’s Flickr group.
Don’t fancy searching through huge amounts of ESO data for that perfect image, but still have an interest in astrophotography? Maybe our Astronomy Photographer of the Year competition is for you instead. Also powered by Flickr, the 2011 competition was launched on the 20th January. Anyone can join the Flickr group to share their images with our community, with no obligation to enter the competition.
If you would like to submit your photos to the competition you can upload 5 in total any time up to 13th July 2011 at noon (GMT). The winners will be announced at a special award ceremony at the Observatory on 8 September 2011, and the very next day the winning images will be on display for the public to enjoy in the Astronomy Photographer of the Year exhibition. You can also look through all the photos in the Flickr group through our special gallery interactive, you could even find yours!
Tom Lowe’s winning Astronomy Photographer of the Year 2010 photo – Blazing Bristlecone
This year we are also offering the opportunity for any member of the Flickr group to select a gallery of their favourite photos. Each month we’ll choose a gallery and use it to make a planetarium short. This will then be shown in London’s only planetarium here at the Observatory. We are particularly looking for galleries that link all the photos together with an interesting story or theme.
Whether you are a keen astrophotographer or prefer looking at the universe through your computer screen we hope you will get involved in this year’s Astronomy Photographer of the Year competition. You can keep in touch with the Astronomy Team via our Twitter feed @ROGAstronomers, or on the Observatory’s Facebook page. We’ll be posting updates that we think could inspire your astrophotography, but we’d also love to hear from you about your top tips for beginners and experts alike.
Get involved and help us make it the best competition yet!
It’s a seasonal staple of carols, Christmas cards and nativity plays but what was the Star of Bethlehem? Astronomical fact or pious fiction, theological symbolism or astrological sign, or simply an inexplicable supernatural event?
The truth is of course that nobody knows for sure, but there are some more and less convincing theories.
The star according to Matthew
Only Matthew’s gospel mentions the star and the Magi or wise men, in the following passage:
After Jesus was born in Bethlehem in Judea, during the time of King Herod, Magi from the east came to Jerusalem and asked, “Where is the one who has been born king of the Jews? We saw his star in the east [or at its rising] and have come to worship him.”… Then Herod called the Magi secretly and found out from them the exact time the star had appeared… After they had heard the king, they went on their way, and the star they had seen in the east [or at its rising] went ahead of them until it stopped over the place where the child was. When they saw the star, they were overjoyed.
(Matthew chapter 2, verses 1-2, 7, 9-10, New International Version)
From this we gather that the star first appeared or rose at a particular time, that it apparently moved (‘went ahead of them’) and stopped, and that to the Magi at least it signified the birth of a ‘king of the Jews’.
Astronomical explanations
Astronomically, it’s been suggested that the star may have been a nova or supernova explosion; a comet; a triple conjunction of Jupiter and Saturn; a close grouping of the three planets Jupiter, Saturn and Mars; a stationary point of Jupiter; or a variable star (one whose brightness changes over time).
Chinese records mention a possible nova or comet in 5BC – an unusually bright star which appeared in the eastern sky for 70 days, and which may have been a nova outburst from the variable star DO Aquilae. This occurred at about the same time as a triple conjunction of Jupiter and Saturn in the constellation of Pisces. The rare combination of these two events may well have been seen by the Magi as a religious sign.
Astrological aspects
It’s likely that the Magi studied astrology, so the star’s astrological aspects are probably at least as important as its astronomical explanation. Rutgers astronomer Michael Molnar has suggested that a double
occultation of Jupiter by the Moon in Aries in 6BC could have astrologically
signified the birth of a divine ‘king of the Jews’.
Theological significance
Others of couse think that the writer of Matthew’s gospel simply invented the star, perhaps to fulfil the Old Testament prophecy that ‘A star will come out of Jacob; a sceptre will rise out of Israel’ (Numbers chapter 24, verse 17). More likely is that Matthew’s star is simply an example of ‘Midrash’ – an established Judaic tradition of theological writing in which non-factual elements can be used to bring out the religious meaning of the factual account. So whether or not there actually was a star is less important than the spiritual message Matthew is trying to convey.
We can’t know for sure whether, what or when the star was. But perhaps the answer is not either/or out of the alternative strands of explanation – astronomical, astrological, theological, supernatural – but both/and. It’s plausible that the Star of Bethlehem was a genuine astronomical event – perhaps a nova associated with a variable star – that had astrological significance to the Magi and theological significance to Matthew.
Whatever the truth is, we wish you a very happy Christmas!
Note: this post is an edited re-posting from last Christmas, based on our fact file about the Star of Bethlehem.
With phones now taking on more and more of the duties usually associated with fully-fledged computers, phone ‘apps’ have become genuinely useful aids for a variety of activities including astronomy. In this blog piece I’ve highlighted three applications for Google Android devices that have great content and prove to be a great help, whether you are observing with the unaided eye or with a telescope. Also, there are many fantastic astronomy applications for other phones. Feel free to add any of your own suggestions in the comments below – our team here at the Royal Observatory Greenwich will also be contributing. Enjoy!
Google Sky Map
Price: FREE
By far the most popular Android astronomy application, Google Sky Map provides a virtual window to peer into space. If your phone has a built-in compass, the application can display the sky wherever you point your phone! Sky Map also has a manual mode to drag your finger across the sky. Stars, constellations, deep sky objects, planets and the Moon are all displayed for your current time and location. Recently, the “Time Travel” feature has been added to see what the sky looks like for any time in the past or in the future. If you’re looking for something in particular such as a planet or galaxy, you can search for it, and a pointer interface will guide you to your target.
Moon Widget
Price: FREE
This no frills app gives you the most important information about the Moon at a glance. Adding this widget to your phone will give you a discrete image of the current phase of the Moon and times for Moonrise and Moonset. Having an application like this helps plan for a nights observations. If the Moon is coming up to, or is in, its full moon phase, then waiting until moonset comes highly recommended. By tapping into the Moon Widget some more detail is given about the Moon’s current location, distance and how many days into the lunar cycle it is. As a preparation before a night of stargazing, this is a great addition to your app collection.
WhereIsIt
Price: $0.99
Just as we use longitude and latitude to mark our location here on Earth, there are equivalents for the night sky so that astronomers around the world can find their chosen target. The coordinates are called Declination (Dec) and Right Ascension (RA), but to make them useful for observing, some calculations are required. WhereIsIt makes the whole process pain-free by taking your current location and time, and converting Dec and RA to altitude and azimuth. Altitude tells you how far up from the horizon you should be looking or pointing your telescope. Azimuth tells you how many degrees (clockwise) around from North to look or aim. If you have the coordinates for your target, you can manually input them or you can select from a list of bright celestial objects including stars, galaxies and nebulae.
There are many more Android astronomy applications that could be mentioned in more detail here, but just try searching for “Astronomy” in the Market and see what you can find! For reviews of some of the top iPhone astronomy apps, check out this month’s edition of the Sky at Night magazine and don’t hesitate to contribute to the comments section below! Also, check out the Royal Observatory Greenwich facebook page here for the latest info on events and astronomy news!
Don’t forget to change the clocks this Saturday evening and claim your annual extra hour in bed on Sunday morning.
At 1.00 am GMT (2.00 am BST) on Sunday 31 October 2010 clocks go back one hour as civil time changes from British Summer Time (BST) to Coordinated Universal Time (almost identical to Greenwich Mean Time).
The Ninth European Parliament and Council Directive on Summer Time Arrangements states that summer (or daylight saving) time will be kept between the last Sunday in March to the last Sunday in October. The changes will take place at 01.00 GMT.
Find out more about daylight saving time and British Summer Time at nmm.ac.uk/bst.
23 September 2010 – The autumnal equinox occurred this morning at 03:09 (UTC).
At the times when the Sun is crossing the celestial equator (the projection of the Earth’s equator onto the sky), day and
night are of nearly equal length at all latitudes so we call these
dates the equinoxes (= ‘equal night’).
In fact, night and day are not exactly equal at the time of the equinox. This is because the Earth’s orbit around the Sun is elliptical not circular, and the Earth moves fastest when it is closest to
the Sun and slowest when furthest away. This causes
variations in the length of the solar day and in time sof sunrise and sunset, so the Sun is not at its highest in the sky at precisely local noon each day.
Find out more about equinoxes and solstices in our fact file.
