Solar Astronomy Archives

May 5, 2008December 24, 2015 by Nancy Atkinson

Mission to the Sun

Astronomy — Solar Probe Spacecraft. Credit: NASA/Johns Hopkins University Applied Physics Laboratory

A mission to the sun is difficult stuff. For 30 years scientists and engineers have struggled with developing a spacecraft that could survive the harsh environment close to the sun, but always ended up running into insurmountable technology limitations or blowing the top off the budget. But now the Applied Physics Lab believes they have come up with a plan that will work, and NASA has given them the go-ahead to get a mission ready by 2015. And contrary to the old joke about a mission to the sun, the new Solar Probe won’t have an easy time of it by just heading to the sun at night!

The Solar Probe mission will come within 6.6 million kilometers (4.1 million miles) of the sun to study the streams of charged particles the sun hurls into space. The spacecraft will actually be within the sun’s corona — its outer atmosphere — where the solar wind is produced. At closest approach the Solar Probe will zip past the sun at 210 km (125 miles) per second, protected by a carbon-composite heat shield able to withstand up to 1425 degrees Celsius (2,600 degrees Fahrenheit) and survive blasts of radiation and energized dust at levels not experienced by any previous spacecraft.

The spacecraft will weigh about 1,000 pounds. Preliminary designs include a 2.7 meter (9 feet) diameter, 15 centimeter (6 inches) -thick, carbon-foam-filled solar shield atop the spacecraft body, similar to APL’s MESSENGER spacecraft.

The probe will be solar powered (no problem there!) with two sets of solar arrays that will retract or extend as the spacecraft swings toward or away from the sun during several loops around the inner solar system, making sure the panels stay at proper temperatures and power levels. At its closest passes the spacecraft must survive solar intensity more than 500 times what spacecraft experience while orbiting Earth.

“Solar Probe is a true mission of exploration,” says Dr. Robert Decker, Solar Probe project scientist at APL. “For example, the spacecraft will go close enough to the sun to watch the solar wind speed up from subsonic to supersonic, and it will fly though the birthplace of the highest energy solar particles. And, as with all missions of discovery, Solar Probe is likely to raise more questions than it answers.”

Solar Probe will use seven Venus flybys over nearly seven years to gradually shrink its orbit around the sun, coming as close as 4.1 million miles to the sun, about eight times closer than any spacecraft has come before.

The main goals of the Solar Probe are to determine the structure and dynamics of the sun’s magnetic field, trace the flow of energy that heats the corona and accelerates the solar wind, and explore dusty plasma near the sun and its influence on solar wind and energetic particle formation. This mission will also help us learn more about the sun-Earth relationship.

Original News Source: Eureka Alert

April 3, 2008December 24, 2015 by Ian O'Neill

There is No Sun-Link with Global Warming

The connection between solar activity and global warming has been a contentious issue for a long time. The idea that cosmic rays create global cloud cover just doesn’t seem to be working out; even the highest estimates of cloud cover variation caused by cosmic ray flux predict the effect to be very small. Now UK scientists have stepped into the debate, producing scientific evidence that there is no link between global warming, cosmic rays and solar activity. Sorry global warming sceptics, we might have to cut back on the emissions after all…

The connection between solar activity and global warming is thought to go like this: The Sun experiences massive changes in energy output throughout the 11-year solar cycle. At its peak (at solar maximum), the Sun’s influence over local space is at its highest. Its massive magnetic field will envelop the Earth and spiral into interplanetary space. As it does so, the immense and large-scale solar wind will deflect high energy cosmic rays. So, counter-intuitively, when the Sun is at its most active, cosmic ray collisions with the atmosphere is at its lowest. It is has been predicted by scientists such as Henrik Svensmark at the Danish National Space Center (DNSC) that these high energy cosmic rays will impact the Earth’s atmosphere, create droplets of water, thus generating cloud cover. So, following this logically, we should have a global decrease in cloud cover during periods of high solar activity (when cosmic rays are not deflected by the solar wind), causing global warming (as there will be less clouds to reflect the solar radiation). Many of the climate problems we are having at the moment can then be attributed to the Sun and not human activity.

But there’s a problem. As previously reported by the Universe Today, research groups will often publish conflicting results about the cosmic ray effect on cloud production. In one of the most definitive results to come out of this area of study has just been announced by UK scientists, and guess what? The Sun/cosmic-ray theory has no measurable effect on the climate change we are currently experiencing.

Dr. Svensmark’s idea was central to the science behind the documentary “The Great Global Warming Swindle” where the human impact on global climate change was brought into question. This theory has been under fire since its conception by highly regarded scientists such as Mike Lockwood from the UK’s Rutherford-Appleton Laboratory. Svensmark stands by his work. So with this in mind, Dr. Terry Sloan from Lancaster University set out to prove Svensmark’s hypothesis. But the results aren’t pretty.

“We tried to corroborate Svensmark’s hypothesis, but we could not […] So we had better carry on trying to cut carbon emissions.” – Dr. Terry Sloan

In a separate study, Giles Harrison from Reading University, also studied the effect of cosmic ray flux on the amount of cloud cover, stating it is an important area of research, “…as it provides an upper limit on the cosmic ray-cloud effect in global satellite cloud data“. Although restricted to the atmosphere above the UK, Harrison’s study also returns the verdict that there is only a very weak cosmic ray effect on cloud production.

The Intergovernmental Panel on Climate Change (IPCC) released a report last year pointing the finger at human activity as the root cause behind global warming. There are very strong correlations between carbon emissions and global warming since the 1970s, so the IPCC has strongly recommended that the international community make radical cuts to their carbon emissions. What’s more the IPCC point out that the contribution from greenhouse gas emissions outweighs the effect of solar variability by a factor of 13 to one.

“…as far as we can see, he has no reason to challenge the IPCC – the IPCC has got it right.” – Dr. Terry Sloan

Source: BBC

April 2, 2008December 24, 2015 by Ian O'Neill

Source of the Slow Solar Wind Found (Video)

The solar wind comes in two modes: fast and slow. Solar astronomers have a good idea as to where the fast solar wind comes from: polar coronal holes of open magnetic field lines, blasting solar particles at speeds of over 3 million km/hr. But what about the slow solar wind which fires particles into space at a pedestrian 1.5 million km/hr? We know it comes from the streamer belt above equatorial regions of the Sun, but we have never been able to look lower. But now, with the help of the Hinode observatory, stunning high-resolution images and video have been captured showing solar dynamics previously overlooked. The point at which the Sun ejects slow wind particles into space can now be studied in unparalleled detail to help us understand the dynamics of space weather and solar storms.

The Sun is a complex, magnetic body. Its magnetic field is highly dynamic, varying in activity throughout the 11-year solar cycle. We have just witnessed the Sun entering “Solar Cycle 24” (although some old sunspots from the previous cycle have just been seen) and it will gradually build in energy before reaching “solar maximum” in a few years time (looks like the solar storms will be bigger than 2003’s flare excitement).

This time of relative calm (known as “solar minimum”) allows solar physicists to study the less explosive dynamics in the lower corona (the Sun’s atmosphere), chromosphere and photosphere. It is in this region that magnetic field lines (or magnetic flux) are pushed through the photosphere and the plasma from the solar interior is guided by the magnetic flux high into the corona. These hot and bright arcs of magnetism and superheated plasma are known as coronal loops, the scene of rapid reconnection events, sometimes sparking flares and coronal mass ejections (CMEs). But this time the Hinode science team have observed a steady release of solar plasma, venting from the solar interior around a cluster of bright coronal loop footpoints. The location of this steady release of plasma forms the origin of the slow solar wind.

“It is fantastic to finally be able to pinpoint the source of the solar wind – it has been debated for many years and now we have the final piece of the jigsaw. In the future we want to be able to work out how the wind is transported through the solar system.” – Prof. Louise Harra, University College London, Mullard Space Science Laboratory.

See the Hinode video of the region generating solar wind particles…

These dazzling images were captured by the Extreme Ultraviolet Imaging Spectrometer (EIS) on board the Japanese Hinode solar observatory. The observatory, which orbits the Earth, constantly looking at the Sun, has given us unrivaled observations of the Sun in X-ray and EUV wavelengths. Launched by Japan, the project also has collaborators in the UK and US.

These new discoveries are of vast importance to us. The solar wind carries a stream of highly energetic particles from the Sun and into space. The solar wind bathes the Earth in a radioactive stream, carrying the remnants of the solar magnetic field with it. The magnetic field can interact with the Earth’s magnetic field, allowing solar particles to rain down on our Polar Regions, creating vast light displays: the Aurora. However, these particles are also highly dangerous to any unprotected astronaut or sensitive satellite orbiting our planet. It is of paramount importance that as we venture further and further into space that we forecast the characteristics of the solar wind before it hits us. These new observations will aid our understanding of the conditions at the solar wind source and greatly improve our space weather-predicting ability.

Source: ESA

April 2, 2008December 24, 2015 by Tammy Plotner

The Sun’s Magnetic Fountains

For you solar observing fans, enjoy the beauty. Over the years both the public and astronomers alike have witnessed the Sun’s volatile and ever-changing atmosphere. Before our eyes huge geysers of hot gas spew into the solar corona at tens of thousands of km per hour. Every few minutes they erupt and reach dynamic proportions. Now a team of scientists have used the Hinode spacecraft to find the origin and progenitor of these fountains – immense magnetic structures that thread through the solar atmosphere.

Today at the Royal Astronomical Society National Astronomy Meeting in Belfast (NAM 2008), team leader Dr. Michelle Murray from the Mullard Space Science Laboratory (MSSL, University College London) presented the latest results from Hinode spacecraft combined with computer emulated solar conditions. Since its launch in October 2006, scientists have been using Hinode to examine the solar atmosphere in extraordinary detail. One of it’s premier instruments is the Extreme Ultraviolet Imaging Spectrometer. The EIS generates images of the Sun and gives information on the speed of the moving gases.

At the core of the solar magnetic field, immense jets of hot gas are forced to the surface through increases in pressure. Just like an earthly geyser, when the pressure releases the gases fall back towards the Sun’s surface. But what causes the pressure? Unlike the volcanic activity that drives the terrestrial phenomena, solar fountains are caused by rearrangements of the Sun’s magnetic field, a continual process that results in looping cycles of increasing and decreasing pressure.

“EIS has observed the Sun’s fountains in unprecedented detail and it has enabled us to narrow down the fountains’ origins for the first time”, comments team member and MSSL postgraduate student Deb Baker. “We have also been able to find what drives the fountains by using computer experiments to replicate solar conditions.”

The sun-observing Hinode satellite is now in a sun-synchronous orbit, which allows it to observe the sun for uninterrupted periods lasting months at a time. Using a combination of optical, EUV and X-ray instrumentation Hinode will study the interaction between the Sun’s magnetic field and its corona to increase our understanding of the causes of solar variability.

“The computer experiments demonstrate that when a new section of magnetic field pushes through the solar surface it generates a continual cycle of fountains”, explains Dr. Murray, “but new magnetic fields are constantly emerging across the whole of the solar surface and so our results can explain a whole multitude of fountains that have been observed with Hinode.”

April 2, 2008December 24, 2015 by Nancy Atkinson

STEREO Spacecraft Captures Footage of a Solar Tsunami

A solar tsunami blasted its way through the sunâ€™s lower atmosphere on May, 19 2007, and the action was captured by the twin STEREO spacecraft. Solar tsunamis are launched by huge explosions near the Sun’s atmosphere, called coronal mass ejections (CMEs). Although solar tsunamis share much in common with tsunamis on Earth, the solar version can travel at over a million kilometers per hour. Last yearâ€™s tsunami blasted and rolled for about 35 minutes, reaching peak speeds around 20 minutes after the initial flare. The observations were made by a team from Trinity College, Dublin.

“The energy released in these explosions is phenomenal; about two billion times the annual world energy consumption in just a fraction of a second. In half an hour, we saw the tsunami cover almost the full disc of the Sun, nearly a million kilometers away from the epicenter,” said David Long, a member of the team that made the observations.

STEREO’s Extreme Ultraviolet Imager (EUVI) instruments monitor the Sun at four wavelengths which correspond to temperatures ranging between 60,000 and 2 million degrees Celsius. At the lowest of these temperatures, scientists can see structures in the chromosphere, a thin layer of the solar atmosphere that lies just above the Sun’s visible surface. At temperatures between 1 and 2 million degrees Celsius, scientist can monitor features at varying levels in the solar corona.

The SOHO spacecraft, which was launched in 1995, also monitors the Sun at these wavelengths but only took images four times per day, giving scientists rare snapshots of these tsunamis. STEREO’s EUVI instruments take an image every few minutes to create a series, making it possible for scientists to track how the wave spreads over time.

Click here for a Quicktime animation of the event.

This is the first time that a tsunami has been observed at all four wavelengths, which enabled the team to see how the wave moved through the different layers of the solar atmosphere.

“To our surprise, the tsunami seems to move with similar speed and acceleration through all the layers. As the chromosphere is much denser than the corona, we’d expect the pulse there to drag. It’s a real puzzle,” said Dr. Peter Gallagher, another member of the team.

To complicate matters, the interval between images is not the same for all four cameras. At the time of the tsunami, the cameras monitoring radiation at 1 million degrees Celsius were set to take an image every 2.5 minutes. They recorded much higher speeds and accelerations for the wave than the other cameras, which were on 10 or 20 minute cycles. By taking a sample of one image in four, the data from these cameras matched the lower values observed in the other layers.

“We’ve thought for some time that the tsunamis might be caused by magnetic shockwaves but, in previous snapshots, the waves appeared to be travelling too slowly. However, we’ve seen from this set of observations that if the time interval between images is too long, it’s easy to underestimate the speed that the waves are moving. With a few more rapid-sequence observations of solar tsunamis, we should finally be able to identify the cause of these waves,” said Gallagher.

The discovery will be presented by David Long at the RAS National Astronomy Meeting in Belfast on Wednesday April 2, 2008.

For more information and animations, see Trinity College’s pageabout the solar tsunami.

Original News Source: RAS press release

April 1, 2008December 24, 2015 by Tammy Plotner

Solar Corona Revealed by Medical X-Ray Techniques

For several decades solar scientists have been hard at work trying to unravel the mysteries of the solar corona. Thanks to a medical x-ray technique known as tomography, scientists are able resolve solar activity in greater detail. By using a new way of processing images, active regions now take on dimensions never foreseen by computer models.

Today Dr. Huw Morgan presented his results to the Royal Astronomical Society National Meeting in Belfast. Using an adapted medical X-ray technique, scientists have produced the first detailed map of the structure of the Sun’s outermost layer, the corona. The application known as tomography uses a series of images taken from many different angles to reconstruct a 3-dimensional map created from direct solar observations.

“This is a breakthrough for scientists trying to understand the corona and the solar wind. We’ve been attempting to apply tomography to the solar corona for more than 30 years but it’s proved very difficult and very inaccurate until now. The new technique that I’ve developed is only in its infancy but shows great potential for areas of research like space weather,” said Dr Morgan, of the University of Aberystwyth.

The process has not been as easy one, nor is it a new idea. Without images of the coronal far side, researchers were left with only half the data. The near side produces its own difficulties as well, since the outermost areas of the corona are more than a thousand times fainter than the regions near the Sun. This factor introduces huge potential errors to observations. Thanks to Dr. Morgan, his new way of processing coronal images, called Qualitative Solar Rotational Tomography (QSRT), eliminates the steep drop in brightness and associated errors. With the help of SOHO’s LASCO instrument, Dr. Morgan applied the technique to a series of images taken as the Sun’s rotation brings the ‘missing’ areas into view. The result? Full coronal maps that are at least 5 times more detailed than previous tomographical studies of the Sun. And the future may hold far more. Says Morgan:

“I’ve now produced maps of the corona over almost a whole cycle of solar activity, so we can now see in unprecedented detail how structures develop and evolve in three-dimensions. The maps have produced some interesting results: for instance we’ve observed large areas of dense structures when the Sun is most active that are not predicted by current computer models. We’ve also found evidence that inner regions of the corona rotate at different speeds.”

According to the RAS press release, the technique is already being used by scientists at the Institute of Maths and Physics at Aberystwyth University to interpret their radio-wave observations of the solar wind. Dr. Morgan, together with colleagues at the Institute of Astronomy at the University of Hawaii, is also using the maps to interpret ultraviolet observations of the corona. Says Dr. Morgan:

“These maps will also prove useful in the important field of space weather. Explosions at the Sun travel through space and often hit the Earth. These energetic magnetic clouds can disrupt communication, power supplies and be a major health hazard for astronauts and airline pilots. Understanding and predicting these storms is a major goal of solar science. The ability to map the whole 3D structure of the corona is a critical step towards achieving this goal.”

March 26, 2008December 26, 2015 by Ian O'Neill

The Sun Bursts to Life: Sunspots, Flares and CMEs

The new sunspots appearing as the Sun rotates (credit: Greg Piepol)

As if to remind us it is still there, the Sun has put on an explosive show of sunspots, flares and coronal mass ejections (CMEs). This is quite surprising as only last month it was declared that the Sun had just started a new solar cycle, and a period of minimum activity. Up until now, the solar disk has been void of any observable features… but like an invasion party, three sunspots have rotated into view, showing complex arcs of magnetic fieldlines (coronal loops), blasting plasma into space by the biggest flare observed this year. Observers have also recorded the radio burst from the CME, so if you want to know what a CME sounds like, read on…

The Sun undergoes an 11 year cycle, beginning at “solar minimum”, culminating at “solar maximum”, and then calming down toward minimum again. At solar minimum, the Sun’s magnetic field lines, reaching from pole to pole, are at their least stressed state. As the cycle progresses, the differential rotation of the Sun (i.e. the Sun rotates quicker at its equator) drags the magnetic field lines around the solar body like an elastic band. As time goes on, the magnetic field lines become so stressed and coiled that massive loops of magnetic flux breaks through the solar photosphere (the solar “surface”). As the Sun’s atmospheric layers are hotter than the Sun’s interior (a situation known at the “coronal heating problem“), as the magnetic loops of flux appear through the photosphere, the cooler interior is exposed. When this happens, sunspots appear; the cooler interior looks darker than the surrounding photosphere, therefore creating a spot, or a “sunspot”.

If there are a lot of sunspots, the magnetic field is most stressed, and the Sun is at its most active. The magnetic flux may get so stressed that it may “reconnect” with opposite polarities, releasing huge amounts of energy as flares. Coronal mass ejections may be unleashed from these flare events, sending hot solar plasma into space. If directed at the Earth, these CMEs can cause damage to satellites, astronauts, even whole power grids on the ground. Predicting space weather (i.e. observing solar dynamics) is therefore paramount to scientists.

Interestingly, these sunspots are not from a new cycle, they are actually “left overs” from the previous cycle. Solar astronomers know this by analysing Michelson Doppler Imager (MDI) images from the Solar and Heliospheric Observatory (SOHO) currently observing the Sun. The MDI instrument has revealed that the sunspots are of the same polarity as the spots from the previous solar cycle, and not from “Solar Cycle 24“.

Yesterday, the Sun unleashed an M2-class solar flare which in-turn created a large CME, propagating away from the solar disk. The CME was not directed toward Earth. A radio astronomer in New Mexico, Thomas Ashcraft, recorded the sound coming from his 21 MHz radio telescope during the event. He heard a strange “heaving sound” as the shock wave on the leading edge of the CME generated radio waves.

Listen to the sound of the radio wave emission from a CME as it travels from the Sun.

“It was a Type II solar radio burst.” – Thomas Ashcraft, remarking on his observation of the CME.

Space weather predictions suggest there is a 50% chance of more M-class flares in the next 24 hours, so the world’s solar telescopes will be watching and waiting…

For more stunning images of the Sun by Greg Piepol (like the sunspots pictured at the top) see: http://www.sungazer.net/032508h.html

Source: spaceweather.com

March 18, 2008December 26, 2015 by Tammy Plotner

Celebrate Sun-Earth Day 2008 on March 20

Over the past seven years, NASA Sun-Earth Connection Education Forum has sponsored and coordinated education and public outreach events to highlight NASA Sun-Earth Connection research and discoveries. Their purpose is to interest school students and the general public to participate in programs that occur throughout the year and the kickoff is about to begin. This year’s main event will be on March 20, 2008.

Sun-Earth Day isn’t strictly limited to this single day. It’s a combination of programs and events throughout the year and celebrated this year on March 20. Middle schools are invited to participate, learn about solar science, solar energy and career choices. Following the events will prepare participants to watch a total solar eclipse on August 1, 2008 via a live web cast from China!

A wealth of website related resources provided by a collaboration of partners that include science centers and museums around the world, the Exploratorium, NASA Connect, Sun-Earth Connection missions and others, offer up awesome experiences like watching a Polar Sunrise. All you need is an Internet connection to visit the unscripted and unpredictable look into some of the latest information on Space Weather, Sun-Earth Day, Solar Week and the new ‘student based’ Space Weather Action Center at NASA Edge where they’re currently featuring programs on “The Sun-Earth Connection” and “Magnetospherence”. Visit the Solar Week website for educational classroom activities and games geared for upper elementary, middle and high school students with a focus on the Sun-Earth connection. Students learn about solar eclipses, sunspots, and solar storms through a series of activities, games, and lessons.

Get involved in Public Outreach! You don’t have to be in a classroom to share your love of astronomy and the Sun-Earth connection. Materials are available that have been specifically designed for you, the museums, planetaria, parks, youth clubs, and educators from community organizations around the globe. A wealth of Hands-On Sun-Earth Day Activities are available. Why not try enabling an idle computer at work with the Sun-Earth Viewer? Take the time to read a Sun-Earth Day Book to your children or grandchildren. It’s as easy as visiting the site and taking few moments to download.

Do you want more? Learn about the aurora at Dancing in the Night Sky or how NASA engineers and researchers use data analysis and measurement to predict solar storms, anticipate how they will affect the Earth, and improve our understanding of the Sun-Earth system at Having A Solar Blast. Don’t forget other great resources like NASA TV or music at Rock Our World. Visit the download site and pick up great movies like “Introduction to the STEREO Mission – Solar Terrestrial Relations Observatory” and “Blackout: The Sun-Earth Connection”.

No matter what you choose to do, Sun-Earth Day is a great time to share with others and have fun!

February 22, 2008December 26, 2015 by Nancy Atkinson

Ulysses Spacecraft Dying of Natural Causes

“One equal temper of heroic heart
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.”
—from the poem “Ulysses” by Alfred, Lord Tennyson

The Ulysses spacecraft has been heroically studying our sun for more than 17 years, almost four times its expected lifetime. But now, the mission might be finally succumbing to the harsh environment of space. Mission managers say the spacecraft will likely “die” in the next month or two.

“Little remains; but every hour is saved
From that eternal silence, something more,
A bringer of new things;
To Follow knowledge like a sinking star,
Beyond the utmost bound of human thought.”
(more from “Ulysses”)

Ulysses is a joint mission between ESA and NASA that was launched in 1990 during space shuttle mission STS-41. Ulysses was the first mission to study the environment of space above and below the poles of the Sun. The spacecraft has returned a huge amount of data that has changed the way scientists view the Sun and its effect on the space surrounding it.

Ulysses is in a six-year orbit around the Sun. Its long orbital path carries it out to Jupiter’s orbit and back again. The further it ventures from the Sun, the colder the spacecraft becomes. If it drops to 2ºC, the spacecraft’s hydrazine fuel will freeze.

This has not been a problem in the past because Ulysses carries heaters to maintain a workable on-board temperature. The spacecraft is powered by the decay of a radioactive isotope and over the 17-plus years, the power it has been supplying has been steadily dropping. Now, the spacecraft no longer has enough power to run all of its communications, heating and scientific equipment simultaneously.

“We expect certain parts of the spacecraft to reach 2ºC pretty soon,”says Richard Marsden, ESA’s Ulysses Project Scientist and Mission Manager. This will block the fuel pipes, making the spacecraft impossible to maneuver.

The ESA-NASA project team had tried to solve this problem by temporarily shutting of the main spacecraft transmitter, which would provide 60 watts of extra power that could be channeled back to the heater and science instruments. Unfortunately, the transmitter failed to turn back on.

“The decision to switch the transmitter off was not taken lightly. It was the only way to continue the science mission,”says Marsden, who is a 30-year veteran of the project, having worked on it for 12 years before the spacecraft was launched.

After many attempts, the Ulysses project team now consider it highly unlikely that the X-band transmitter will be recovered. They believe the fault can be traced to the power supply, meaning that the extra energy they hoped to gain cannot be routed to the heater and science instruments after all.

So, the spacecraft’s fuel lines are gradually freezing. This spells the end of this highly successful mission.

“Ulysses is a terrific old workhorse. It has produced great science and lasted much longer than we ever thought it would,” says Marsden. “This was going to happen in the next year or two, it has just taken place a little sooner than we hoped.”

The team plan to continue operating the spacecraft in its reduced capacity for as long as they can over the next few weeks. “We will squeeze the very last drops of science out of it,” says Marsden.

“Death closes all; but something ere the end,
Some work of noble note, may yet be done…
‘Tis not too late to seek a newer world…
To sail beyond the sunset.”
—more from “Ulysses” by Tennyson

Original News Source: ESA Press Release

February 13, 2008December 26, 2015 by Ian O'Neill

Real-Time Solar Storm Warning Now Operational, Protecting Astronauts and Satellites

Highly energetic solar particles are generated by solar flares and can be harmful to astronauts and sensitive satellite circuits. Solar flares are most likely to occur during periods of heightened solar activity (i.e. during solar maximum at the peak of the 11 year solar cycle), and future manned missions will need to be highly cautious not to be unprotected in space at these times. Many attempts are underway at forecasting solar activity so “solar storms” can be predicted, but a form of early warning system is required to allow time for astronauts to seek cover and satellites put in a low-power state. Now, using the Solar and Heliospheric Observatory (SOHO), scientists are testing a new method of detecting high energy solar ions, in real-time.

Using SOHO as an early warning system isn’t a new idea. Ideally positioned at the Sun-Earth First Lagrange Point (L₁), SOHO orbits its little island of gravitational stability in direct line of sight to the Sun, 1.5 million km from the Earth. Anything that comes from the Sun will have to pass through the L₁ point, firing through any robotic observers positioned there.

SOHO is in good company. Also positioned at the L₁point is the Advanced Composition Explorer (ACE)Â that takes measurements of the solar wind as solar particles continue their way toward the Earth. However, the advanced instrumentation on SOHO allows it to detect very fast electrons (near-relativistic) as they are generated by the Sun. The Comprehensive Suprathermal and Energetic Particle Analyzer (COSTEP) instrument onboard SOHO has provided data about highly energetic particles since 1995, but it’s never been in real-time. Now, using a new technique, solar scientists are able to receive particle data with an hour warning of an impending storm of energetic ions.

When a flare explodes via magnetic interactions on the Sun, electrons and ions are accelerated and burst into space. Travelling at high speed, electrons reach SOHO much quicker than the heavier ions. What’s more, the relativistic electrons are harmless, so they provide an ideal, safe, indicator that the damaging ions are following behind.

The forecasting method was developed eight months agoÂ by Dr Arik Posner (Southwest Research Institute, USA) and scientists from the University of Kiel (Germany), NASA’s Goddard Space Flight Center (USA) and the University of Turku (Finland). Oliver Rother from the University of Kiel has seen the potential for the new real-time system and explains, “We were so excited by Posner’s project that we immediately teamed up and developed new software that displays the data and can give a warning three minutes after taking the measurements 1.5 million km away.”

This is obviously good news for any astronaut in Earth orbit, but generally they are protected from intermediate solar storms as they are within the protective shield of the magnetosphere. This system will be most useful for the future colonists of the Moon and any long-haul manned missions to Mars. It may only be an hours warning, but that hour could make allÂ the difference between mission success and mission failure.

Source: SpaceRef.com