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ROSAT – Fiery Debris To Rain From The Sky

ROSAT Credit: NASA

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The recent re-entry of the UARS satellite was not the end of falling satellite debris, as the German ROSAT X-ray observatory satellite will soon crash back to Earth.

Last month NASA’s large UARS satellite re-entered the atmosphere and burned up over the Pacific Ocean, with about 500 kg of debris falling into the water. But the smaller Roentgen Satellite or ROSAT will have approximately 30 pieces equaling 1.5 tons that will resist burn up and make it to the surface.

The largest piece of the satellite expected to reach the surface is the heat-resistant, 32 inch, 400 kg mirror.

Compared to UARS, there is an increased chance of someone being hit by a piece of the falling debris. The odds have been estimated as a 1 in 2,000; UARS was 1 in 3,200.

As with UARS, it is unknown where ROSAT will burn up and where its remaining parts will impact the surface, however the satellite is expected to re-enter between the 21st and 24th of October. The Center for Orbital and Re-Entry Debris studies predicts October 23, 2011 a 06:40 UTC ± 30 hours.

For up to date predictions check the Centre for Orbital and Re-Entry Debris Studies.

Prediction Ground Track Credit: Center for Orbital and Reentry Debris Studies

Until then, you can keep an eye out for the small satellite as it is a naked eye object. It’s nowhere near as bright as the ISS, but it is visible. Check Heavens Above or Spaceweather for predictions of when it will pass over your location.

The 2.4 ton Roentgen Satellite (ROSAT) was launched by NASA in 1990 as a joint venture between Germany, Britain and the USA.

The satellite was designed to catalogue X-ray sources in deep space and mapped around 110,000 stars and supernovae. It also discovered that some comets emit X-rays. It was permanently damaged in 1998, and its mission was officially ended in February of 1999.

ROSAT will soon meet its fiery end; will you see it pass over before then?

Keep an eye out for that falling mirror.

Credit: NASA
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Did The Draconids Perform?

Draconid Meteor Over Somerset UK Credit: Will Gater www.willgater.com

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After weeks of speculation of its intensity, the Draconid/Giacobond meteor shower finally arrived. Some astronomers predicted that this normally quiet meteor shower would deliver up to 1000 meteors per hour at its peak – Were they right?

At approximately 20:00 BST (21:00 UT) on October 8th 2011 the shower started in earnest and many in the UK and Europe looked forward to an evening of meteor watching.

Unfortunately, many people were under thick clouds and missed the display, but there were a few places where the clouds cleared and observers were treated to a memorable spectacle.

I have done many meteorwatch evenings in the past, but this one got exciting very quickly and the uncertainty of the amount of meteors was soon doused.

Many people including myself were popping outside and trying to glimpse meteors through the clouds, but most of the time the Meteorwatch Meteor Live View was being used.

Everything was fairly sedate apart from us all moaning about the weather, but then all of a sudden at approximately 20:30 BST (19:30 UT) The Meteor Live View app on the Meteorwatch website went crazy!

Meteor Live View Credit: meteorwatch.org/ Norman Lockyer Observatory UK

Many people started to get good breaks in the clouds including myself and there were reports of dozens of meteors in just a few short minutes, much to the envy and disappointment of those still clouded over.

At this time the International Meteor Organisation (IMO) reported observations of just over 300 meteors per hour (319 ZHR).

The evening continued and to everybody’s delight (to those who could see meteors), there were many. I saw 3 within a couple of seconds and this continued for about an hour.

Eventually rates started to decline, people saw less and the Meteor Live View started to show less activity.

At approximately 22:00 BST (21:00 UT) meteor activity dropped substantially – The show was over!

The IMO results were posted on their website with rates of just under 350 meteors per hour at the peak of the shower, reported by their observing stations.

Credit: IMO

Did the Dracondids/ Giacobonids live up to expectations in the end? I would say yes, a fairly heavy meteor shower, maybe it could be called a mini storm!

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The Draconid Meteor Shower – A Storm is Coming!

Geminid Meteor - George Varros (courtesy NASA)

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The Draconids are coming! Will this meteor shower produce a storm of observable meteors, or just a minor squall? The Draconid Meteor Show should begin on October 8, 2011 starting at dusk (roughly 19:00 BST) and continue through the evening. Peak activity of this normally minor and quiet shower is estimated to be at 21:00 BST (20:00 UT). There seems to be a wide range of predictions for this year’s shower, but some astronomers believe there could be up to 1,000 meteors per hour, making this a meteor storm!

The Draconids or Giacobinids as they are also known, radiate from a point in the constellation of Draco the Dragon in the Northern hemisphere. In the past, notably in 1933 and 1946, the Draconids turned into a meteor storm with meteor rates of more than one every second!

So, will this year bring us a storm? Astronomers believe so as the predicted path of the Earth through the debris streams of comet 21P/Giacobini-Ziner is favorable for a major storm, similar to what has been seen in previous years. Some reports say NASA is even considering the potential risk of damage to the International Space Station and other satellites due to meteroid impacts.

Some astronomers, on the other hand, are saying this shower could be a dud, with only 5 or so meteors per hour.

Credit: Alex Tudorica

Observers in the UK and Northern Europe are ideally placed to see the peak of the Draconids. Unfortunately the peak occurs in the day time for North America. There will also be a bright Moon which may drown out many but the brightest meteors, but if predictions are correct, you will still see many. You may see Draconid meteors on the 7th an the 9th also, so it is worth going out and checking the skies.

The Constellation Draco in the northern sky in the northern hemisphere.

Draco is a circumpolar constellation visible all night from northern latitudes.

There is no skill or even astronomical knowledge needed to enjoy meteor showers. All you need is to be comfortable, away from bright lights and your eyes. Sit back on a recliner or garden chair and fill your gaze with sky as meteors can appear anywhere as they radiate from the constellation of Draco. For more info on how to enjoy meteor showers visit meteorwatch.org

So what will you see? Draconid meteors are usually slow and bright streaks of light, but if you look away, you can still miss them so keep your gaze on the sky.

There are no guarantees of a meteor storm or even a good meteor shower as these phenomena can be very unpredictable, but the only way to find out is to go outside and look up.

If predictions are correct, you could be in for a spectacular treat and something truly memorable, so don’t miss it. Even if it is cloudy, you can listen to the meteor shower or you can watch as they enter Earths atmosphere

For more information on the Draconids, see the International Meteor Organization’s post on this year’s shower.

Good Luck!

Fireball Meteor
Credit: Pierre Martin of Arnprior, Ontario, Canada.
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What’s That Very Bright Star – Is it the Planet Jupiter?

Jupiter Credit: John Talbot

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Have you seen a very bright star rising in the East every night the past few months? If you’re a night owl, you may have noticed it moves across they sky from the East into the West, shining brightly throughout the night. However this object is not a star! It’s the planet Jupiter and it is the brightest object in the night sky at the moment, apart from the Moon.

At the end of October Jupiter will be at opposition. This means the mighty planet (the largest in our solar system) will be directly opposite the sun as seen from Earth and it will also be at its closest point to Earth in the two planets’ orbits around the Sun. This makes Jupiter or any other object at opposition appear brighter and larger. The opposition of Jupiter occurs on October 29, 2011.

But Jupiter has been gracing our night sky for several months, and will continue to shine brightly as it moves in and out of opposition. But enjoy the view now, as this will be the closest opposition until 2022!

Visually, even with the naked eye, Jupiter is stunning! A burning yellowish-white star-like object, many times brighter than any other stars.

But through a pair of ordinary binoculars or a small telescope, Jupiter comes to life. Not only is it possible to see the disc of the Planet, you can also see the four Galilean moons.

The Galilean moons, Callisto, Ganymede, Europa and Io were discovered by Galileo over 400 years ago and are amazing worlds in their own right.

Callisto is the outermost moon with a very ancient and heavily cratered surface. It is the second largest of the four moons, but does not interact tidally with an “orbital resonance” unlike the other three moons.

Callisto. Image credit: NASA/JPL

Ganymede is the largest of the four moons and is also the largest moon in the Solar system, being larger than the Planet Mercury. The bizarre surface is a mix of two types of terrain – highly cratered dark regions and younger, but still ancient regions with a large array of grooves and ridges. Ganymede is the only moon in the solar system to have its own magnetosphere.

Ganymede
Ganymede Credit: NASA

Europa is the second closest moon and is also the smallest. It has one of the smoothest and newest surfaces in the solar system, being covered purely with ice. Europa is likely a water world and it is believed that below its icy surface, lies a deep moon-wide ocean surrounding a warm mantle. It is one of the most likely places to harbour life in the solar system.

Europa from Galileo
Europa from Galileo

Io is the innermost of the four Galilean moons of Jupiter and third largest. It is the most geologically active body in the solar system with over 400 active volcanoes and an ever changing and hostile surface of sulphur and silicates.

Io Credit: NASA

When you look up tonight and stare at Jupiter, or you are looking at it through binoculars or a telescope, just think – Jupiter and the four Galilean moons are a very interesting place, almost a mini solar system with our larger solar system!

Occasionally you will see Jupiter’s “Great Red Spot” or the shadow of one of the moons on Jupiter’s surface. The Jupiter system is always changing.

If you want to find out what the positions are for the moons, use planetarium software such as Stellarium and then have a look yourself.

Good luck!

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An Easy Guide To Observing the Aurora

Dundee Aurora Credit: Ben-e-boy

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With the recent solar activity and the high possibility of more coming up, here is an easy guide to observing the aurora. An aurora is a natural light display high in the Earth’s atmosphere, caused by energetic particles from the Sun, colliding with the Earth’s magnetic field.

These light displays are called the Aurora Borealis in the Northern hemisphere and Aurora Australis in the Southern hemisphere, but are commonly known as the Northern and Southern lights.

Viewing aurorae is incredibly simple, but the conditions need to be right for a display to appear.

Normally you can only see aurorae near the poles, such as in Canada, Iceland, and Norway or southern Australia and Antarctica, but when the Sun is highly active, more solar material is thrown in Earth’s direction, creating powerful geomagnetic storms. These storms can bring auroral displays further south to areas such as Southern UK and North to mid latitudes of the USA.

The intensity scale is known as the Planetary KP index and basically the higher the KP number the further south Aurorae can be seen, KP 8 or higher can be good for observers further south. To find out what current levels are check spaceweather.com or the Geophysical Institute at the University of Alaska Fairbanks

Credit spacewether.com

If aurora activity is predicted to be high and there is a possibility of seeing it at your location, try and find an area away from light pollution or bright lights and let your eyes adjust to the dark. This may require you to travel into the countryside to escape bright city light pollution.

The best time to spot aurora is around local midnight, but this can change depending on viewing conditions and the current intensity of the magnetic storm.

Once you are comfortable and your eyes have adjusted to the dark, face north (or south in the Southern Hemisphere).

You do not need binoculars, a telescope, or any other optical aid other than glasses if you wear them.

Look low and close to the horizon and look for the faint green/ reddish glow of aurora. It may be quite difficult to see at first, but if it is a powerful display it can be very easy to spot.

I live in the South of the UK and have seen the waving bands and curtain like structures quite easily in powerful geomagnetic storms.

If you have a camera that takes long exposures, use a tripod and try to image the aurora and send us your results.

Most of all, enjoy the show! Good luck!

Aurora caught over Karlstad, Sweden on September 27, 2011. Credit: Socrates2013 on Flickr

Aurora September 26, 2011 From Acadia National Park Credit: hale_bopp37
Aurora Behind the Clouds Credit: Corinne Mills
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Massive Sunspot 1302

Sun Set with the Massive Sun Spot 1302 (Upper left on the Sun) Credit: Adrian Scott

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A highly active region on the Sun threatens to deliver powerful geomagnetic storms over the week ahead. Highly energetic solar eruptions are likely heading in our direction to give Earth’s magnetic field a significant glancing blow!

Over the past few days the new sunspot AR1302 has been incredibly active, hurling massive X-class solar flares into space and it will soon face Earth.

The massive sunspot, many times larger than the Earth (see images below) is expected to increase in size and energy, and is expected to release powerful solar flares, sparking strong geomagnetic storms.

Sun Spot AR1302 through the clouds Credit: Tavi Greiner

What does this mean for the Earth and it inhabitants?

The Earth experiences material ejected from the Sun on a daily basis and we are protected by the Earth’s own magnetic field. This is normal and has been happening since the birth of the solar system. But occasionally the Sun erupts and sends vast quantities of solar material our direction in the form of Coronal Mass Ejections (CME’s).

This can trigger very powerful geomagnetic storms, which can damage satellites in orbit and cause problems for communications and power networks. One positive outcome, though, is amazing displays of aurorae at the poles (Northern and Southern Lights).

Sunspot 1302 is expected to eject material towards Earth over the next few days, so look for news of strong geomagnetic activity and displays of aurorae.

Several observers are reporting that AR1302 is easily visible on the Sun at sunset or sunrise. Never ever look at the sun with your eyes, or any other optical aid! This will damage your eyesight permanently! The Sun should only be viewed using specialist equipment.

For further updates see Spaceweather.com and NASA’ Heliophysics Science Division

Massive Sun Spot 1302 and Earth size Comparison taken with a specialist solar filter Credit: Will Gater www.willgater.com

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UARS: When and Where Did It Go Down?

Credit: NASA

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After a night of changing predictions and hopes of many to see a fireball in the sky, the UARS (Upper Atmosphere Research Satellite) finally met it’s fiery demise.

The decommissioned, 6.5 ton satellite is believed to have re-entered the Earths atmosphere over the Pacific Ocean, and in it’s death throes the massive satellite broke up, and the surviving debris likely landed in the ocean, off of the West coast of North America.

In regard to the exact re-entry point and position of the debris field, Nicholas Johnson, chief orbital debris scientist at NASA’s Johnson Space Center, said “We don’t know where the debris field might be… We may never know.”

The US Department of Defense’s Joint Space Operations Center at Vandenberg Air Force Base in California and the U.S. Strategic Command radar tracking assessed that the satellite reentered the atmosphere sometime between 0323 and 0509 GMT on September 24, 2011 (the Strategic Command predicted it would re-enter at 04:16 GMT). During this period, the satellite was heading across the Pacific Ocean on a southwest-to-northeast trajectory approaching Canada’s west coast. The mid-point of that groundtrack and a possible reentry location is 31 N latitude and 219 E longitude (green circle marker on the above map).

“If the re-entry point was at the time of 04:16 GMT, then all that debris wound up in the Pacific Ocean,” Johnson said during a media briefing on Saturday. “If the re-entry point occurred earlier than that, practically the entire pass before 04:16 was over water. So the only way debris could have probably reached land would be if the re-entry occurred after 04:16.”

NASA says there are no reports of damage or injury caused by the surviving components that made it to the surface, and there are so far no credible visual reports of anyone seeing the UARS satellite burning up.

The Earth-observing satellite was in orbit for 20 years and 10 days.

Credit: NASA
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Where will the UARS Satellite Crash?

ATV re-entry. Credit: ESA

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The bus sized UARS (Upper Atmosphere Research Satellite) is expected to re-enter Earth’s atmosphere early morning GMT on September 24. Right now, the Center for Orbital and Reentry Debris Studies lists the projected re-entry time as 05:10 UT on Sept. 24, plus or minus 2 hours.

NASA UPDATE “As of 7 p.m. EDT on Sept. 23, 2011, the orbit of UARS was 90 miles by 95 miles (145 km by 150 km). Re-entry is expected between 11 p.m. Friday, Sept. 23, and 3 a.m., Sept. 24, Eastern Daylight Time (3 a.m. to 7 a.m. GMT). During that time period, the satellite will be passing over Canada, Africa and Australia, as well as vast areas of the Pacific, Atlantic and Indian oceans. The risk to public safety is very remote.”

Due to the robust nature of some of the parts on the satellite, it is likely that approximately 500kg of material will impact the ground or water.

The FAA (Federal Aviation Administration) has released a Local Air Safety Information special notice advising of the possibility of space debris.

The calculated risk that you’ll be hit by the falling space debris has been put at 1 in 3,200, said Nick Johnson, chief scientist with NASA’s Orbital Debris Program. But the chance that any one person on Earth getting hit by debris has been estimated at about 1 in 21 trillion.

It is highly unlikely that any injury or damage will be caused by this falling debris and NASA says; “The risk to public safety or property is extremely small, and safety is NASA’s top priority. Since the beginning of the Space Age in the late-1950s, there have been no confirmed reports of an injury resulting from re-entering space objects. Nor is there a record of significant property damage resulting from a satellite re-entry.”

It is still unsure where exactly the UARS satellite will pass over and re-enter the Earth’s atmosphere, but it will be an incredibly bright fireball visible even in daylight. But if some debris ends up near you, don’t worry too much — it won’t be flaming hot. NASA says any pieces of UARS landing on Earth will not be very hot. The heating of objects passing through the atmosphere stops at about 32 km (20 miles) up, and cools after that.

Stay posted for more updates and if you are lucky enough to get an image of UARS burning up please let us know and post your images on our flickr group

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The Mission to Find the Missing Lunar Module

Apollo LM orbiting the sun, Credit: Adrian West http://twitter.com/virtualastro

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Where is the Apollo 10 Lunar lander module? It’s somewhere out there — orbiting the Sun — and there’s a new initiative to try and find it!

The Apollo 10 mission launched on May 18, 1968 and was a manned “dry run” for its successor Apollo 11, testing all of the procedures and components of a Moon landing without actually landing on the Moon itself.

After carrying out a successful lunar orbit and docking procedure, the Lunar Module (called “Snoopy”) was jettisoned and sent into an orbit around the Sun.

After 42 years, it’s believed to still be in a heliocentric orbit and a team of UK and international astronomers working with schools are going to try and find it.

The idea is the brainchild of British amateur astronomer Nick Howes who helped coordinate a very successful asteroid and comet project with schools and Faulkes Telescope during this past summer.

After consulting with people from NASA’s Jet Propulsion Laboratory and other orbital dynamics experts, the Howes has assembled a team of facilities and experts, including the Faulkes Telescope, Space Exploration Engineering Corp, astronomers from the Remanzacco Observatory in Italy and schools across the UK.

They know they have a massive undertaking ahead of them to find Snoopy.

“The key problem which we are taking on is a lack of solid orbital data since 1969,” Howes told Universe Today. “We’ve enlisted the help of the Space Exploration Engineering Corp who have calculated orbits for Apollo 10 and working closely with people who were on the Apollo mission team in the era will help us identify search coordinate regions.”

“We’re expecting a search arc anywhere up to 135 million kilometres in size which is a huge amount of space to look at, ” Howes continued. “We’re aware of the scale and magnitude of this challenge but to have the twin Faulkes scopes assist the hunt, along with schools, plus the fact that we’ll doubtless turn up many new finds such as comets and asteroids makes this a great science project too. We’re also encouraging anyone to have a go as we’ll be posting the coordinates on to the Faulkes Telescope website starting in a few days”

While the challenge ahead of Howes and the team is enormous, and the chances of the team finding Snoopy are very small, the team are enthusing thousands of people with their own “Apollo Mission” – the mission to find the missing Apollo Lunar module.

Credit: Faulkes Telescope