The May Sky

posted May 7, 2017, 4:45 PM by Chris Crowe   [ updated May 7, 2017, 4:49 PM ]

Although Jupiter reached opposition and peak visibility exactly one month ago, it remains a stunning sight nearly all night. It appears about 40° above the southeastern horizon an hour after sunset and climbs highest in the south around 11 p.m. local daylight time. As a bonus this evening, a waxing gibbous Moon appears just a few degrees away. The pair lies among the background stars of Virgo, though only 1st-magnitude Spica some 10° below appears conspicuous thanks to the bright Moon nearby. When viewed through a telescope, Jupiter’s disk spans 43" and shows a wealth of detail in its atmosphere.
Mars continues to put on a nice show in late April. It appears 10° high in the west-northwest an hour after sunset and doesn’t dip below the horizon until 10 p.m.

Jupiter’s moons typically line up with the giant planet’s equator. Because the moons’ orbital plane currently tilts 3° to our line of sight, they can sometimes appear oddly skewed. Tuesday's sky affords a perfect example. Io, Ganymede, and Callisto appear in a straight line that is at a 40° angle to Jupiter’s equator. The closest alignment occurs between roughly 1:00 and 1:30 a.m. on the 10th. 

Wednesday, May 10

Full Moon occurs at this evening, and our satellite looks completely illuminated all night. You can find it low in the southeast peaking in the south around 6 a.m. The Moon lies among the background stars of Libra the Scales.

The dark side of the moon is a myth.
In reality both sides of the Moon see the same amount of sunlight however only one face of the Moon is ever seen from Earth. This is because the Moon rotates around on its own axis in exactly the same time it takes to orbit the Earth, meaning the same side is always facing the Earth. The side facing away from Earth has only been seen by the human eye from spacecraft.

The Moon is drifting away from the Earth.
The Moon is moving approximately 3.8 cm away from our planet every year. It is estimated that it will continue to do so for around 50 billion years. By the time that happens, the Moon will be taking around 47 days to orbit the Earth instead of the current 27.3 days.

The Moon has quakes.
These are caused by the gravitational pull of the Earth. Lunar astronauts used seismographs on their visits to the Moon, and found that small moonquakes occurred several kilometres beneath the surface, causing ruptures and cracks. Scientists think the Moon has a molten core, just like Earth.

The first spacecraft to reach the Moon was Luna 1 in 1959.
This was a Soviet craft, which was launched from the USSR. It passed within 5995 km of the surface of the Moon before going into orbit around the Sun.

Spring Sky

posted Mar 13, 2017, 3:01 AM by Chris Crowe   [ updated Mar 13, 2017, 3:14 AM ]

Venus shines brilliantly in the western sky after sunset all week. At magnitude –4.5 this evening, the inner planet glows about two magnitudes brighter than the evening sky’s second-brightest point of light, Jupiter. Venus shows up easily within a half-hour after sunset and remains on view until about 7:30pm over Harrow. When viewed through a telescope, Venus about 7 percent illuminated this evening. 

Full Moon occurred last night (12th March), but our satellite will look completely illuminated all night. You can find it rising in the east shortly after sunset and peaking in the south around 1:30 a.m. The Moon lies among the background stars of western Virgo, roughly 25° west-northwest of Jupiter.

Mars continues to put on a nice show these March evenings. It appears 20° high in the west once twilight fades to darkness and doesn’t set until after 10 p.m. local daylight time. The magnitude 1.4 Red Planet lies among the background stars of Aries the Ram. Unfortunately, Mars shows no detail on its 4"-diameter disk when viewed through a telescope.

By 9 p.m. this evening, you can find Jupiter rising in the eastern sky in the company of a gibbous Moon. The two skate across the sky in tandem, reaching their peak altitudes in the south during the wee hours. The giant planet shines at magnitude –2.4 this week against the backdrop of central Virgo constellation, some 5° north-north of that constellation’s brightest star, 1st-magnitude Spica. Even a small telescope reveals Jupiter’s large-diameter disk and four bright moons.

As midnight approaches, look to the east for the bright star Arcturus. At magnitude 0.0, it is the second-brightest star visible from mid-northern latitudes. If you scan about 20° to the left and a little below this luminary, you should see a conspicuous semicircle of stars — the constellation Corona Borealis (the Northern Crown). It’s the most prominent group of stars having a shape reminiscent of a circle, and it makes a fitting target for Pi Day. (For you non-geeks, Pi Day is 3/14 (14/3 for us Brits!) because the first three digits of the mathematical constant pi are 3.14. Pi is the ratio of a circle’s circumference to its diameter, so today we celebrate all things circular!

Thursday, March 16
If you head outside after darkness falls tonight and look due west, you’ll see the stars of Taurus the Bull nearly halfway to the zenith. The tip of the V-shaped Hyades star cluster, which forms the Bull’s face, points straight toward the horizon. To the right of the Hyades lies the spectacular Pleiades star cluster (M45) and to the left are the glittering jewels that form Orion the Hunter’s shape. Target Jupiter through a telescope tonight and you’ll think the planet has a “black eye.” The dark shadow of the solar system’s largest moon, Ganymede, transits the gas giant’s cloud tops starting at 1am. The moon itself starts to transit the planet’s disk a few hours later.

Saturn rises around 2am and climbs some 25° high in the south-southeast by the time morning twilight begins. The ringed planet shines at magnitude 0.5 and lies in the northwestern corner of Sagittarius the Archer. When viewed through a telescope, Saturn shows a 17"-diameter disk surrounded by a stunning ring system that spans 38" and tilts 26° to our line of sight.

November Supermoon!

posted Nov 13, 2016, 10:06 AM by Chris Crowe   [ updated Nov 13, 2016, 10:37 AM ]

This year, the full moons of October, November and December all take place when the moon is at its closest point of approach in its orbit around Earth — a so-called supermoon. 

The next supermoon will be November's full Beaver Moon, which is expected to reach the peak of its full phase on Monday Nov. 14 at 1352 GMT, but it will appear full to the casual observer in the day before and after the main event. It is the second of three consecutive supermoon full moons for 2016. This full moon will be not only the closest and brightest supermoon of 2016 but also the largest since 1948, What's more, the full moon won't come this close to Earth again until Nov. 25, 2034.

1.Supermoons Occur Each Year
A supermoon happens about once a year and are viewable from both the Northern and Southern hemispheres. Keep an eye to the sky and lookout for the next one heading toward Earth in Aug. 2014.

2.Supermoons Will Get Smaller
Get your supermoon fix while you can; the moon is moving on to greener pastures. Supermoons will get smaller in the distant future because the moon is slowly propelling itself out of Earth's orbit, moving 3.8 centimeters farther from Earth each year. Scientists suspect that at formation, the moon started out about 14,000 miles (22,530 kilometers) from the planet, but now, it's about about 238,900 miles (384,402 kilometers) away.

3. Supermoons Change the Tides ... But Not Much
A supermoon might be able to change the tides slightly, but it certainly won't cause natural disasters, experts have said. The full phase of the moon causes higher tides, but adding a supermoon on top of it doesn't create any significant difference. Scientists count themselves lucky if they're able to see any difference in tide level at all. Usually, the supermoon causes the tide to change by less than an inch, if at all.

4. Winter Supermoons Are Supersized
Does the moon look larger in the winter? It should. The Earth is closest to the sun in December each year, meaning that the star's gravity pulls the moon closer toward the planet. Because of this effect the largest supermoons happen in the winter.

5. Not All Supermoons Are The Same
The perigee between the Earth and the moon can vary by as much as the diameter of the Earth during any given month. Although that might seem like a large number, on average, the moon is about 30 Earth diameters away from the planet. The sun's gravity is actually responsible for pulling the Earth and moon into a closer alignment, causing the orbital variation.

6. It Won't Make You Crazy
Have no fear: The supermoon will not turn you into a lunatic. Studies have shown that a full moon of any kind does not affect human behaviour. Full moons and supermoons do not cause more mental hospital admissions, psychiatric disturbances, homicides or any other crime.

7. A Supermoon Won't Destroy Earth
Despite the claims of some people around the world, the supermoon will not destroy the Earth. The supermoon happens when the moon is at perigee — the point in its orbit that brings it closest to Earth — and in its fullest phase. The supermoon is a normal occurrence since the moon is on an elliptical orbit, and will not make Earth's orbit go out of whack!

October Observing - 17th October 2016

posted Oct 17, 2016, 4:46 AM by Chris Crowe   [ updated Oct 17, 2016, 5:32 AM ]

Uranus' peak visibility, Orionid meteor shower, and other awesome things to look for in the sky this week!

Saturn remains a gorgeous sight in the evening sky all week. It stands about 15° high in the southwest an hour after sunset and doesn’t set until 9 p.m. local daylight time. The ringed world shines at magnitude 0.5 among the background stars of southwestern Ophiuchus. When viewed through a telescope, Saturn shows a 16"-diameter disk surrounded by a dramatic ring system that spans 35" and tilts 26° to our line of sight.

Full Moon officially arrived at 12:23 a.m. EDT two days ago. You can find it rising in the east around sunset and peaking in the south just before 1 a.m. local daylight time. It dips low in the west by the time morning twilight starts to paint the sky. The Moon lies in southern Pisces near that constellation’s border with Cetus. October’s Full Moon also goes by the name “Hunter’s Moon.” In early autumn, the Full Moon rises about half an hour later each night compared with a normal lag close to 50 minutes. The added early evening illumination supposedly helps hunters track down their prey.

Orionis Metor Shower
Although the Orionid meteor shower peaks this morning, a waning gibbous Moon shares the sky and will drown out many of the fainter “shooting stars.” Still, observers can expect to see half a dozen or so meteors per hour before morning twilight commences. Orionid meteors appear to radiate from the northern part of the constellation Orion the Hunter.

Uranus reaches opposition and peak visibility this week. Opposition officially arrived at 7 a.m. on Friday, when the outer planet lies opposite the Sun in our sky. This means it rises at sunset, climbs highest in the south around 1 a.m. local daylight time, and sets at sunrise. The magnitude 5.7 planet lies in southern Pisces some 2.6° northwest of magnitude 4.8 Mu (m) Piscium. Although Uranus normally shines brightly enough to glimpse with the naked eye under a dark sky, you won’t see it tonight because the Full Moon lies just 3° to its south. Use binoculars to locate the planet or, better yet, wait until the bright Moon isn’t so close. A telescope reveals Uranus’ blue-green disk, which spans 3.7".

Brilliant Venus stands out low in the southwest during evening twilight. The planet lies about 10° above the horizon a half-hour after sunset and sets as twilight comes to a close. At magnitude –3.9, Venus is the brightest object in the evening sky after the Moon. Although you’ll be hard-pressed to see any background stars against the twilight, the inner world officially passes from the constellation Libra into Scorpius today. 

Mars continues to put on a nice show these October evenings. The magnitude 0.2 Red Planet lies among the background stars of Sagittarius and appears some 20° high in the south-southwest after darkness falls. A telescope shows the planet’s 8"-diameter disk, which should show a few subtle dark markings during moments of good seeing. While you look at Mars this evening, it should have a new visitor from Earth sitting on its surface. The European Space Agency’s ExoMars Schiaparelli module is scheduled to touch down on martian soil shortly before 11 a.m. EDT. Although largely a test to demonstrate the technology needed for future missions, Schiaparelli will capture 15 black-and-white images on its way to the surface.

Look high in the east after darkness falls this week, and you should see autumn’s most conspicuous star group. The Great Square of Pegasus stands out in the evening sky at this time of year, though it appears balanced on one corner and looks more diamond-shaped. These four almost equally bright stars form the body of Pegasus the Winged Horse. The fainter stars that form the rest of this constellation’s shape trail off to the square’s west.

Transit of Mercury

posted May 9, 2016, 3:43 AM by Chris Crowe   [ updated May 9, 2016, 3:52 AM ]

On Monday 9 May astronomers will be treated to a rare occurrence as Mercury passes across the face of the Sun, appearing as a dark dot traversing the bright solar disc.This event, known as a transit, will be visible from most of western Europe, including the UK and Ireland, as well as South America and the eastern parts of North America.

Transits of Mercury are rare, with only 13 or 14 occurring each century. After Today's transit the next one will not be until 11 November 2019.

The event lasts for 7.5 hours, from 12:12 BST until 19:40 BST, so you have plenty of time to observe this rare occurrence for yourself, provided the weather remains sunny and clear! ESA will be live streaming the event, but the transit can be observed using a dedicated solar telescope or properly filtered astronomical telescope, such as the Lunt solar scope which we have in the Rayleigh Observatory.

We’ll be trying to capture this on camera; you are welcome to come and (safely) look at the Sun with us! The Rayleigh observatory will also be open this week at the following times for all staff at the school:

Today 9th May 1:30-2:15 Observing the transit of Mercury
                        4-5pm Observing the transit of Mercury
                        9-11pm Jupiter, Mars, crescent Moon, double cluster

Tue 10th May 9-11pm Jupiter, Mars, M12, crescent Moon, double cluster

Wed 11th may 11-11:50pm Saturn, Jupiter, M10

You are all very welcome to join us, families too. The Observatory is located on the roof of the physics department, accessible through the department door on Football Lane. Feel free to communicate this to those who do not have access to email, and we hope to see you there.

Let’s hope for clear skies!

Gravitational Waves Discovered!

posted Feb 22, 2016, 4:02 AM by Chris Crowe   [ updated Feb 22, 2016, 4:06 AM ]

Gravitational Waves 2016 Discovery

A fortnight ago gravitational waves were detected by the LIGO experiment in America; a truly huge discovery. Many boys asked ‘why did they bother to look for them?’. That leads on to the fundamental question ‘why study astronomy’?

Although it's not why we bother to research, one possible response would be to lead off with the unexpected benefits of fundamental research. Einstein never predicted that his work would have practical relevance, but without the time dilation corrections from his theories, our modern GPS systems wouldn't work. Therefore, interesting new discoveries can have entirely unexpected consequences.

Another way of answering is that we have now developed a new sense with which to view the Universe. Nearly every time in the history of science, and certainly in astronomy, when this has happened it has resulted in completely unexpected discoveries and a completely new way of thinking of our place in the Universe. We can't judge discoveries only by their technological payoff, but must also look at the new discovery space they open up; the ability to access new and unexpected information.

Of course, there is also the pure wow factor. Two 30 solar mass black holes orbiting at near the speed of light and merging, sending ripples through space itself 1.3 billion years ago that we’ve detected as vibrations in the fabric of space 1/1000th the size of the proton. That's why we as astronomers got involved in research, not because of the practical relevance!

It is an important question to thoughtfully address as there is a reasonable amount of money spent on these experiments (although it pales in comparison to that spent on defence). We must answer on all fronts: The benefit of fundamental research for unexpected payoffs, the pure value of seeing our place in the universe in a new way, and the wonder it instills in us.

LIGO is a technical tour de force, and efforts of that kind push the limits in engineering, not just physics. LIGO is measuring things at levels orders of magnitude more precisely than ever before. Pursuing these questions is a fundamental part of being human, yet in today's world it has become increasingly important to be able to justify the pursuit of the answers.

The fruits of scientific and technological development in astronomy, especially in areas such as optics and electronics, have become essential to our everyday life, with applications such as digital cameras, WiFi, communication satellites, mobile phones, Global Positioning Systems, tomography, missile systems, solar panels and Magnetic Resonance Imaging (MRI) scanners. Although the study of astronomy has provided a wealth of tangible, monetary and technological gains, perhaps the most important aspect of astronomy is not one of economic measure. Astronomy has and continues to revolutionize our thinking on a worldwide scale. In the past, astronomy has been used to measure time, mark the seasons, and navigate the vast oceans. As one of the oldest sciences astronomy is part of every culture’s history and roots. It inspires us with beautiful images and promises answers to the big questions. It acts as a window into the immense size and complexity of space, putting Earth into perspective and promoting global citizenship and pride in our home planet.

January - February 2016 - 5 Planets Visible

posted Feb 22, 2016, 4:00 AM by Chris Crowe   [ updated Feb 22, 2016, 4:56 AM ]

Mercury, Venus, Mars, Saturn and Jupiter have put on a spectacular show before dawn in recent weeks. All five have been visible together in a graceful arc across the predawn sky. In late January and early February, the moon swung past the planets, but by mid-February Mercury is getting harder to see. Soon, it will be too close to the rising sun to be visible from Harrow. All of us can still see four planets at once though, Venus, Mars, Saturn and Jupiter remain visible before dawn, and Jupiter is also visible in the evening after about 9pm. Don’t miss the moon in the vicinity of Jupiter for several evenings, centered on February 23.

Big Bang Cosmology: Creating the Universe in 14 Billion Years

posted Sep 30, 2015, 8:08 AM by Chris Crowe   [ updated Sep 30, 2015, 8:09 AM ]

Download the full presentation with videos here

Supermoon Lunar Eclipse!

posted Sep 28, 2015, 11:15 AM by Chris Crowe   [ updated Sep 28, 2015, 12:41 PM ]

An awe-inspiring blood-red ‘supermoon’ cast its eerie gaze across Harrow School between about 1am and 5am this morning with a total lunar eclipse. The moon is currently at its closest point to the Earth and appears 30% larger and brighter than when at its furthest. This event hasn’t happened since 1982 and won’t be repeated until 2033. The Rayleigh Observatory captured the event. The rusty-red moon was completely within the Earth’s shadow from 03:11 to 04:24. The eclipse ended when the moon left the shadow at 06:24. Amazingly the British weather held out for the duration with hardly a cloud in the sky.

Throughout history, these incredibly rare events have been associated with major global events and disasters, but luckily we saw it through unscathed. Here are some of the photos and videos we took during the eclipse:

New star systems found in Orion nebula!

posted Jun 3, 2015, 8:25 AM by Chris Crowe   [ updated Jun 12, 2015, 7:54 AM ]

We have discovered something quite amazing right in the middle of our Orion Nebula image, which featured last year in the Harrow Record. Following the recent discovery in the heart of the nebula of newly created solar systems by the Hubble Space Telescope, we decided to look more closely at our own image to see what if anything we could find. To our astonishment, we were able to locate at least one of these objects along with its characteristic 'bow shock' - a rapidly expanding arc of gas and dust surrounding the new star. 

Here is our image compared to a Hubble image:

                                Rayleigh Observatory                                                                     Hubble Space Telescope

Zooming right into the centre of the images reveals the objects:


Zooming right into the heart of the beast again:
                                        Rayleigh                                                                                      Hubble

Here we can see the new star systems and the bow shock clearly visible on the Rayleigh image...

                                        Rayleigh                                                                                      Hubble

...showing that the school observatory is capable of producing discovery-quality data, even at the level of the Hubble Space Telescope!

Of course, being much larger and above the Earth's atmosphere, and costing 300,000 times as much as the Rayleigh Observatory, Hubble can zoom in yet further still to produce these amazing close-ups of the new star systems:

Hubble Space Telescope close-ups

Each of these objects will go on to form a solar system, and for the first time we have imaged them with the our RC400 reflecting Telescope. The total observing time was over 24 hours, with lots of processing to bring out the detail in the image. The massive difference in the pixellation in the above images shows what effect having a huge telescope in space has for you!

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