Astronomer, writer and much much more. The best Astronomy, Space info on twitter. Making Stargazing easy, fun and enjoyable for all.
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An artist's conception of Reaction Engines' Skylon spacecraft. Credit: Reaction Engines
After 30 years of development, the UK and European space agencies have given a go for the Skylon Spaceplane.
The Skylon, which is being developed at the Oxfordshire-based Reaction Engines in the UK, is an unpiloted and reusable spacecraft that can launch into Low Earth Orbit after taking off from a conventional runway.
Looking like something out of Star Wars, Skylon is a self contained, single stage, all in one reusable space vehicle. There are no expensive booster rockets, external fuel tanks or huge launch facilities needed.
The vehicle’s hybrid SABRE engines use liquid hydrogen combined with oxygen from the atmosphere at altitudes up to 26km and speeds of up to Mach 5, before switching over to on-board fuel for the final rocket powered stage of ascent into low Earth orbit.
The Skylon is intended to cut the costs involved with commercial activity in space, delivering payloads of up to 15 tons including satellites, equipment and even people into orbit at costs much lower than those that use expensive conventional rockets.
Once the spacecraft has completed its mission, it will re-enter Earth’s atmosphere and return to base, landing like an airplane on the same runway, making it a totally re-usable spaceplane, with a fast mission turn around.
Skylon has received approval from a European Space Authority panel tasked with evaluating the design. “No impediments or critical items have been identified for either the Skylon vehicle or the SABRE engine that are a block to further development,” the panel’s report concludes.
“The consensus for the way forward is to proceed with the innovative development of the engine which in turn will enable the overall vehicle development.”
The UK Space Agency says that Reaction Engines will carry out an important demonstration of the SABRE engine’s key pre-cooler technology later this summer.
Soon you may see an eerie spectacle on clear summer nights if you are located at latitudes between 50° and 70° north and south of the equator: Noctilucent Clouds.
These ghostly apparitions are a delight to see and are quite rare. It is incredibly difficult to predict exactly when they will appear, but we do know they should begin to appear soon.
The season for Noctilucent Clouds (Noctilucent = Latin for “Night Shining”) starts early June and continues into late July. They are seen just after dusk, or before dawn and an apparition can last around an hour.
These mysterious clouds, with their bizarre tenuous wispy shapes reminiscent of ripples in sand or the changing surface of a pool of water, spread like a glowing web across the northern sky. Colours can range from brilliant whites, with tinges of blue, pink and orange.
Formed by tiny ice crystals, they are the highest clouds in the Earth’s atmosphere, located in the mesosphere at altitudes of around 76 to 85 kilometers (47 to 53 miles) almost at the edge of space.
They are normally too faint to be seen, and are visible only when illuminated by sunlight from below the horizon, while the lower layers of the atmosphere are in the Earth’s shadow. Noctilucent clouds are not fully understood and are a recently discovered meteorological phenomenon, only being recorded for about 120 years.
Noctilucent clouds can only form under very restrictive conditions, and their occurrence can be used as a guide to changes in the upper atmosphere. Since their relatively recent classification, the occurrence of noctilucent clouds appears to be increasing in frequency, brightness and extent.
There is evidence that the relatively recent appearance of noctilucent clouds and their gradual increase, may be linked to climate change. Another recent theory is that some of these bright displays come from particulates and water vapour in the atmosphere left over from Space Shuttle launches.
How can you see them? Over the next couple of months look north during dusk and dawn and try and spot this mysterious and elusive phenomenon. They are best seen when the sun is between 6 and 16 degrees below the horizon, and seem to occur more frequently in the Northern hemisphere than the Southern.
Good luck!
Noctilucent clouds over Blair, Nebraska, USA. Credit: Mike Hollingshead
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During the month of May, four bright Planets will grace the morning sky just before dawn.
The planets Venus, Jupiter, Mercury and Mars will be involved in a series of conjunctions (close together) and will finally be joined by the thin crescent moon at the end of the month.
Twice during May some of the planets will converge to form a trio, where 3 planets will fit in an imaginary circle roughly 5 degrees across.
On the 11th Mercury, Venus and Jupiter will be within 2.5 degrees of each other, forming a very tight trio and on the 21st another trio will be formed by Mercury, Venus and Mars.
Dawn Planets 21st May Credit: Adrian West
On the 29th, 30th, and 31st, the waning crescent moon will arrive, moving past Jupiter, Mars, Venus and Mercury stretched out in a line across the eastern sky.
Dawn 29th May. Credit: Adrian West
Unfortunately, these gatherings will be a challenge especially for observers in high latitudes, as the ecliptic in May is very shallow and low to the horizon. But if all you need is a challenge to get you out observing, then here’s your chance!
Venus and Jupiter should be easy objects to see, but Mercury and Mars will be very difficult, along with the crescent moon due to the onset of daylight.
Be careful as you will be viewing objects close to the sun. Never ever look at the sun with the naked eye, binoculars or a telescope as this will permanently damage your eyes or blind you. Viewing the sun can only be done with specialist solar telescopes and equipment.
Nanosail-D Pass Credit: Vesa Vauhkonen, Spaceweather.com
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Over the next few weeks, skywatchers will have excellent viewing opportunities for the NanoSail-D solar sail.
The satellite is coming to the end of its 95-day mission to test the viability of de-orbiting decommissioned satellites or space debris. NanoSail-D is now de-orbiting and slowly losing altitude in the Earths thin upper atmosphere.
As the satellite descends, viewing opportunities will improve.
To see NanoSail-D pass over, you will need to know exactly when it will be visible from your location. To do this, go to Heavens-above.com or Spaceweather.com where star charts with times and pass details will be displayed after you enter your observing site.
Once you know the time and location in the sky of the pass of the satellite, make sure you are able to get a good view of the part of the sky where the satellite due to appear. Give yourself plenty of time, go outside and get ready. I always set a 30 second reminder on my watch or cell phone, so I don’t have to fumble around or guess the time.
To enjoy the NanoSail-D passes:
• Make sure you know the right place in the sky and the time of the pass, by checking on the web.
• Make sure you will be able to get a clear view of it from your viewing location.
• Set an alarm or get ready for the pass as it only lasts a few seconds.
• NASA expects NanoSail-D to stay in orbit through May 2011.
• If you are an astrophotographer, don’t forget, NASA and SpaceWeather.com are having an imaging contest of NanoSail-D. Find out more here.
• Most of all, get your friends and family outside with you to watch NanoSail-D and enjoy!
Artist concept of Nanosail-D in Earth orbit. Credit: NASA
On April 29th, 2011, the space shuttle Endeavour is scheduled to blast off for the last time, delivering the Alpha Magnetic Spectrometer and an ExPRESS Logistics Carrier to the International Space Station.
If you live in the UK you can watch the launch live on NASA TV and a number of other sites on the internet, but that’s not all you can do! You may be able to watch it fly over the UK with your very own eyes about 20 minutes later!
Yes! You can watch the Shuttle fly over the UK roughly 20 minutes after launch (launch time is currently set for 3:47 p.m. EDT – 8:47 p.m. UK Time) if the timing is right and skies are clear. It will be accompanied by its bright orange external fuel tank as it sails across the sky.
I was lucky to see and actually film this in August 2009 with the launch of STS-128 Space Shuttle Discovery.
How to see it? Go outside roughly 15 – 20 minutes after launch and you could see two bright objects similar to what the ISS looks like when it passes over, moving at roughly the same speed. These bright objects in parallel to each other will follow a similar track in the sky to what the ISS does, but it will be the Shuttle Endeavour and its separated external fuel tank!
Hope for clear skies and that the launch isn’t delayed, as this may be our last chance ever of seeing a space shuttle fly over the UK just after launch.
Set your alarm clocks for an early treat about a half an hour before sunrise on Thursday April 28 through Sunday, May 1, 2011, as there will be a planetary delight in store! Go out and with either a pair of binoculars, a small telescope, or just use your naked eyes and find an unobscured view of the Eastern horizon to see a conjunction (objects near each other in the sky) of the planets Jupiter, Mars, Venus and Mercury, below and to the left of the thin crescent moon.
Bright Venus will be easy to spot first, then Mercury followed by Jupiter. The real challenge is to find Mars which will be very close to Jupiter. See the above diagram for help on where each object is located.
If you are unlucky on the first morning, try again the following day for a chance to see this rare planetary occurrence.
While observing this close to the Sun take care and never look at the sun directly with your eyes and never through an optical instrument, as this will permanently damage your eyesight or blind you!
Only special purpose made solar telescopes and filters are safe for viewing the sun.
Do you have a new telescope, or are you considering buying a new one? Hopefully, you have chosen a telescope with the best specifications for your budget, but before you can truly get the best out of your wonderful new window on the cosmos, you need to have something even more important than the scope – Eyepieces!
A lot of people new to astronomy, or new to buying astronomy equipment tend to concentrate on telescopes and unfortunately overlook eyepieces, settling for the basic set of 2 or 3 that come with the new telescope.
Eyepieces are probably the most important part of your observing equipment, as they are at the heart of your setup and can make your observing experience fantastic or disastrous, or make an average telescope great or an excellent telescope bad.
The Basics
Eyepieces are the part you look through and are responsible for magnification of the objects you see through the telescope. They come in many different magnifications and types, but it’s not rocket science. You will soon learn what eyepieces work well for seeing different astronomical objects.
Telescope eyepieces are designed to fit into the focuser of the telescope. Depending on your telescope, they come in two sizes 1.25” or 2” and there is .965” which is an older size and pretty much obsolete, unless you have an old telescope. Most telescopes can be fitted with adapters so both eyepiece sizes can be used.
Magnification
The magnifying power of any eyepiece is a simple equation expressed in millimetres: Divide the focal length of the telescope by the focal length of the eyepiece and your answer is the amount of magnification. Long focal length eyepieces such as 32mm and 25mm are lower magnification, while lower numbers like 10mm and 5mm are magnifying powerhouses.
It is always good practice to start observing an object with a lower power eyepiece such as a 40mm and gradually build up to higher powered eyepieces such as 10mm or lower. The reason for this is the telescope, human eye, seeing conditions and object being observed are all variable. Starting off with a high power such as 4.7mm may be a struggle.
Fainter objects such as nebula and galaxies are usually seen better with lower powers and you can really ramp up the power with bright objects like the moon.
Below are rough guides and are dependent on the telescope you use:
2mm-4.9mm Eyepieces: These are very high magnification and very difficult to use unless seeing conditions are perfect and the object observed is very bright, like the moon.
5mm – 6.9mm Eyepieces: These are good on bright objects such as the moon and bright planets, but are still very high power and work best with steady seeing conditions.
7mm – 9.9mm Eyepieces: These are very comfortable high magnification eyepieces and are excellent for observing brighter objects, a must for any eyepiece collection.
10mm – 13.9mm Eyepieces: These work well for all objects including brighter nebula and galaxies a good mid/high range magnification.
14mm – 17.9mm Eyepieces: These are a great mid range magnification and will help resolve globular clusters, galaxy details and planetary nebulae.
18mm – 24.9mm Eyepieces: These will work nicely to show wide field and extended objects, great mid-range magnification for objects like galaxy clusters and large open clusters.
25mm – 30.9mm Eyepieces: These are wider field eyepieces for large nebula and open clusters. A good finder eyepiece for locating objects before moving to higher powers.
31mm – 40mm Eyepieces: These are excellent for extended views and large star fields and make excellent finder eyepieces before moving to higher powers.
Eye Relief
Eye relief is the distance from the last surface of an eyepiece at which the eye can obtain the full viewing angle. If a viewer’s eye is outside this distance, a reduced field of view will be obtained and viewing the image through the eyepiece can be difficult. Generally longer eye relief is preferred.
Eye Relief Credit: qwiki.com
Apparent Field of View
This is the apparent size of the image in the eyepiece and can range from about 35 to 100 degrees. Larger fields of view are more desired.
Apparent Field of View Credit: starizona.com
Types of Eyepiece
There are many different eyepiece types, some old and now obsolete, some simple and some advanced.
The different types of eyepiece are purely governed by the configuration of the glass and lenses inside the eyepiece. Some giving exceptional eye relief, wide fields of view, colour correction etc.
Some different brands of eyepiece include: Huygens, Ramsden, Kellner, Plössl, Orthoscopic and Kellner.
The most common and popular eyepiece type is the Plössl due to its good all round performance, good eye relief, approximate 50 degree field of view, pinpoint sharpness and good contrast. Plössl eyepieces are made by many manufacturers now, but there are excellent examples from manufacturers such as Meade and Televue.
Finally we have exotic eyepieces such as Super Wide and Ultra Wide which are usually 2” eyepieces, with higher powers up to around 4.7mm at 1.25” and are usually in the domain of the large Dobsonian or Newtonian telescope user, but are just at home on smaller telescopes such as refractors or Cassegrains.
These eyepieces sport amazing eye relief and huge “port hole” 80 – 100 degree views with fully loaded premium optics, which are very forgiving on telescopes with optical aberrations and other problems. They can make average or poor telescopes great, but there is a cost; an example of which is my 14mm Ultra Wide which cost £500 ($800) just for one eyepiece and I have a full set! Combined, my eyepieces are worth much, much more than the telescopes they are used on, but it’s worth it!
Eyepieces are the most important part of your observing equipment, choose them and use them well, which will help you enjoy observing through your telescope.
If you want to find the planet Saturn in the sky this weekend, but aren’t sure where to look, this guide should help you.
Saturn is visible all night long at the moment and is quite easy to find, as it is just past opposition which makes it quite bright.
Credit: Adrian West
Find the constellation of Leo the Lion (high in the Southern sky at around 10pm) by looking for the backwards question mark asterism (red in the diagram), which is the head of Leo. Find the last 2 stars in Leo’s body and draw an imaginary line through these 2 stars, and arc to the left and down until you reach a bright yellowish star. This is Saturn.
If you continue drawing this imaginary line a little further you will find the bright bluish white star Spica, in the constellation of Virgo.
Right now, Saturn should be an easy target to spot with the naked eye, but looks great through binoculars and is truly amazing through any telescope.
April showers? Yes! The 16th to the 26th this month brings us the April Lyrid Meteor Shower, with the peak occurring on April 22nd.
The meteors in this shower tend to be bright and leave persistent trains as they enter the Earth’s atmosphere. In recent years the shower has averaged 10 to 20 meteors per hour.
You may think that this sounds like a fairly mediocre shower and not worth bothering with, but it has been known for the Lyrids to surge and rates rise rapidly to over 100 per hour! This is what makes this shower so interesting and difficult to predict. Will it be a biggy this year or not?
Lyrid meteors radiate from a point (radiant) in the constellation of Lyra and this is where this shower gets its name. The best time to look for Lyrid meteors will late in the evening on April 22nd after 10 pm as the constellation of Lyra rises up from the northeast horizon.
This will give you 2 or 3 hours of meteor watching before the waning gibbous moon rises and starts to wash out the sky. But still, it’s well worth staying up to see as many bright meteors as possible.
If you are new to astronomy, you may ask “what is a Messier Marathon and how do I do one?”
Basically a Messier Marathon is an all night (Dusk til Dawn) observing session held around mid March/ early April every year, where an observer attempts to see all, or as many of the 110 Messier objects as listed by Charles Messier.
The Messier list includes: Nebulae, Galaxies, Star clusters, Supernovae and many other deep sky objects. All of the objects in the Messier list are observable with small amateur telescopes and many of the objects are observable with binoculars.
The reason why Messier marathons take place from mid March to early April is because this is when all of the objects are visible in one evening. Other times of the year aren’t suitable as some of the objects will be in daylight or below the horizon etc.
You don’t have to be an astronomy ace or a seasoned astronomer to do a Messier marathon, but you will need a good telescope to see all of the objects. You don’t even need to do a full Messier marathon as many people do half marathons and depending on your location, or when you observe, you may not be able to see all 110 objects as there is a very tight window of opportunity and higher latitude observers do lose a couple of objects below the horizon.
Timing is key to enable you to see as many of 110 messier objects as possible. Many astronomers put tables and even star charts on the internet to help observers see as many objects as possible.
Observing starts at dusk and ends after dawn and on average each object gets about 5 minutes of observing time before you have to move onto the next one. There can be a short respite half way through the observing session for food and rest, but this depends on the order and success of the objects you are viewing?
Before starting your night of viewing Charles Messier’s wonders, make sure you have all your equipment ready, are dressed warm as it will get cold, have all your charts and viewing tables ready. It also helps to have a hot drink and something nice to eat.
The best dates this year for doing a Messier Marathon have passed and the sky was drenched with the glow of the full moon, but we still have early April. Good luck.
Charles Messier (26 June 1730 – 12 April 1817) was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 “Messier objects”. The purpose of the catalogue was to help astronomical observers, in particular comet hunters such as himself, distinguish between permanent and transient objects in the sky.
