The Moon Is Front And Center During A Total Solar Eclipse

In the lead-up to a total solar eclipse, most of the attention is on the Sun, but Earth’s moon also has a starring role.

“A total eclipse is a dance with three partners: the moon, the Sun and Earth,” said Richard Vondrak, a lunar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It can only happen when there is an exquisite alignment of the moon and the sun in our sky.”

During this type of eclipse, the moon completely hides the face of the sun for a few minutes, offering a rare opportunity to glimpse the pearly white halo of the solar corona, or faint outer atmosphere. This requires nearly perfect alignment of the moon and the sun, and the apparent size of the moon in the sky must match the apparent size of the Sun.

On average, a total solar eclipse occurs about every 18 months somewhere on Earth, although at any particular location, it happens much less often.

The total eclipse on Aug. 21, 2017, will be visible within a 70-mile-wide path that will cross 14 states in the continental U.S. from Oregon to South Carolina. Along this path of totality, the umbra, or dark inner shadow, of the moon will travel at speeds of almost 3,000 miles per hour in western Oregon to 1,500 miles per hour in South Carolina.

In eclipse maps, the umbra is often depicted as a dark circle or oval racing across the landscape. But a detailed visualization created for this year’s eclipse reveals that the shape is more like an irregular polygon with slightly curved edges, and it changes as the shadow moves along the path of totality.

“With this new visualization, we can represent the umbral shadow with more accuracy by accounting for the influence of elevation at different points on Earth, as well as the way light rays stream through lunar valleys along the moon’s ragged edge,” said NASA visualizer Ernie Wright at Goddard.

This unprecedented level of detail was achieved by coupling 3-D mapping of the moon’s surface, done by NASA’s Lunar Reconnaissance Orbiter, or LRO, with Earth elevation information from several datasets.

LRO’s mapping of the lunar terrain also makes it possible to predict very accurately when and where the brilliant flashes of light called Baily’s Beads or the diamond-ring effect will occur. These intense spots appear along the edge of the darkened disk just before totality, and again just afterward, produced by sunlight peeking through valleys along the uneven rim of the moon.

In the very distant future, the spectacular shows put on by total solar eclipses will cease. That’s because the moon is, on average, slowly receding from Earth at a rate of about 1-1/2 inches, or 4 centimeters, per year. Once the moon moves far enough away, its apparent size in the sky will be too small to cover the sun completely.

“Over time, the number and frequency of total solar eclipses will decrease,” said Vondrak. “About 600 million years from now, Earth will experience the beauty and drama of a total solar eclipse for the last time.”

July 14 Solar Flare And A Coronal Mass Ejection

A medium-sized (M2) solar flare and a coronal mass ejection (CME) erupted from the same, large active region of the sun on July 14, 2017. The flare lasted almost two hours, quite a long duration. The coils arcing over this active region are particles spiraling along magnetic field lines, which were reorganizing themselves after the magnetic field was disrupted by the blast. Images were taken in a wavelength of extreme ultraviolet light.

Solar flares are giant explosions on the sun that send energy, light and high speed particles into space. These flares are often associated with solar magnetic storms known as coronal mass ejections (CMEs). While these are the most common solar events, the sun can also emit streams of very fast protons – known as solar energetic particle (SEP) events – and disturbances in the solar wind known as corotating interaction regions (CIRs).

The Solar Dynamics Observatory is managed by NASA’s Goddard Space Flight Center, Greenbelt, Maryland, for NASA’s Science Mission Directorate, Washington. Its Atmosphere Imaging Assembly was built by the Lockheed Martin Solar Astrophysics Laboratory (LMSAL), Palo Alto, California.

February 11th 2017 Penumbral Lunar Eclipse

An eclipse of the moon can only happen at full moon, when the Sun, Earth and moon line up, with Earth in the middle. There are three kinds of lunar eclipses: Total, Partial and Penumbral – At such times, Earth’s shadow falls on the moon creating a lunar eclipse. Lunar eclipse(s) develop at a minimum of two times – to a maximum of five times per year.

In a total eclipse of the moon, the inner part of Earth’s shadow, called the umbra, falls on the moon’s face. At mid-eclipse, the entire moon is in shadow, which mostly appear as shades of gray, and on occasion will appear as shades of reddish/gray.

In a partial lunar eclipse, the umbra appears to take a swath out of a circumference of the moon. The darken shadow grows larger, and then recedes, never reaching the total phase.

In a penumbral lunar eclipse, the diminished outer shadow of Earth falls on the moon’s face. This third kind of eclipse is more subtle and difficult to observe. It is absent of the darker shadow as in a partial eclipse. This eclipse stops short of presenting the dramatic minutes of totality. For those using simple field binoculars or moderate telescopes will be able to witness the transition. If there are clear skies and at the right geographical locations, you will be able to see the event with the naked eye.

NASA astrophysicist Fred Espenak, tells us about 35% of all eclipses are penumbral. Another 30% are partial eclipses, where it appears as if a darkened scoop has been taken out of the moon. And the final 35% go all the way to becoming total eclipses of the moon, a glorious event.

BREAKING NEWS: New Findings Illustrate Secondary Extended Solar Cycles Far Greater Danger than Previously Known

Based on a new study, space scientists at the University of Reading are predicting we are witness to the beginning of a longer-term solar cycle, which will exceed the better-known 11 year and 22 year cycles. Each cycle consist of a ‘solar minimum’ and ‘solar maximum’ measured by the number of sunspots during these periods – and the waxing and waning of charged particles produced by solar flares, coronal mass ejections, coronal holes, and charged filaments.

This research is produced by Dr Mathew Owens, from the University of Reading’s Meteorology department, and Co-author Professor Mike Lockwood FRS, University of Reading. Their paper was published in the journal ‘Scientific Reports’. “The magnetic activity of the Sun ebbs and flows in predictable cycles, but there is also evidence that it is due to plummet, possibly by the largest amount for 300 years”; said Owens.

As the Sun becomes less active, sunspots and coronal ejections will become less frequent. As this trend continues over time, the escalating reduction in solar wind has a direct causal effect on the layers of the Sun’s atmosphere. The most significant effect will be on the ‘heliosphere’ – which like Earth’s magnetic field, shields the Earth dangerous charged particles and radiation.

**I am working on the completion of this study – hope to have it published tomorrow. STAY TUNED…..

Moon Periodically Showered with Oxygen Ions from Earth

A team of researchers affiliated with several institutions in Japan, examining data from that country’s moon-orbiting Kaguya spacecraft, has found evidence of oxygen from Earth’s atmosphere making its way to the surface of the moon for a few days every month. In their paper published in the journal Nature Astronomy, the researchers describe what data from the spacecraft revealed.

Scientists have known for some time that the moon is constantly bombarded with particles from the solar wind and have also known that once a month, as the Earth is positioned between the Sun and moon, the moon is protected from the solar wind. In this new effort, the researchers describe evidence of oxygen ion transport from Earth’s outer atmosphere to the lunar surface during this short periodic time- period.

Prior research has shown that oxygen atoms become ionized in Earth’s upper atmosphere when they are struck by ultraviolet light. Sometimes, this causes them to speed up to the point that they break away from the atmosphere and move into what is known as the magnetosphere, a cocoon that surrounds our planet that is stretched like a flag away from the direction of the Sun due to the solar wind—so far, in fact, that it covers the moon for five days each lunar cycle, causing the moon to be bombarded with a variety of ions. Data from Kaguya now suggests that some of those ions are oxygen. The researchers found that approximately 26,000 oxygen ions per second hit every square centimeter of the moon’s surface during the deluge.

Because the moon is protected from the solar wind by the Earth when the increase in oxygen ions was recorded, the researchers are confident they come from the Earth. Adding even more credence is that the ions were found to be moving slower than those that normally arrive via the solar wind. Also, they note, prior research has found lunar soil samples containing some degree of oxygen-17 and oxygen-18 isotopes, which are not typically found in space, but are found in the ozone layer covering Earth.

Fermi Sees Gamma Rays from ‘Hidden’ Solar Flares

An international science team says NASA’s Fermi Gamma-ray Space Telescope has observed high-energy light from solar eruptions located on the far side of the Sun, which should block direct light from these events. This apparent paradox is providing solar scientists with a unique tool for exploring how charged particles are accelerated to nearly the speed of light and move across the Sun during solar flares.

“Fermi is seeing gamma rays from the side of the Sun we’re facing, but the emission is produced by streams of particles blasted out of solar flares on the far side of the Sun,” said Nicola Omodei, a researcher at Stanford University in California. “These particles must travel some 300,000 miles within about five minutes of the eruption to produce this light.”

Omodei presented the findings on Monday, Jan. 30, at the American Physical Society meeting in Washington, and a paper describing the results will be published online in The Astrophysical Journal on Jan. 31.

Fermi has doubled the number of these rare events, called behind-the-limb flares, since it began scanning the sky in 2008. Its Large Area Telescope (LAT) has captured gamma rays with energies reaching 3 billion electron volts, some 30 times greater than the most energetic light previously associated with these “hidden” flares.

Thanks to NASA’s Solar Terrestrial Relations Observatory (STEREO) spacecraft, which were monitoring the solar far side when the eruptions occurred, the Fermi events mark the first time scientists have direct imaging of beyond-the-limb solar flares associated with high-energy gamma rays.

“Observations by Fermi’s LAT continue to have a significant impact on the solar physics community in their own right, but the addition of STEREO observations provides extremely valuable information of how they mesh with the big picture of solar activity,” said Melissa Pesce-Rollins, a researcher at the National Institute of Nuclear Physics in Pisa, Italy, and a co-author of the paper.

The hidden flares occurred Oct. 11, 2013, and Jan. 6 and Sept. 1, 2014. All three events were associated with fast coronal mass ejections (CMEs), where billion-ton clouds of solar plasma were launched into space. The CME from the most recent event was moving at nearly 5 million miles an hour as it left the Sun. Researchers suspect particles accelerated at the leading edge of the CMEs were responsible for the gamma-ray emission.

Large magnetic field structures can connect the acceleration site with distant part of the solar surface. Because charged particles must remain attached to magnetic field lines, the research team thinks particles accelerated at the CME traveled to the Sun’s visible side along magnetic field lines connecting both locations. As the particles impacted the surface, they generated gamma-ray emission through a variety of processes. One prominent mechanism is thought to be proton collisions that result in a particle called a pion, which quickly decays into gamma rays.

In its first eight years, Fermi has detected high-energy emission from more than 40 solar flares. More than half of these are ranked as moderate, or M class, events. In 2012, Fermi caught the highest-energy emission ever detected from the Sun during a powerful X-class flare, from which the LAT detected high­energy gamma rays for more than 20 record-setting hours.

New Space Weather Model Helps Simulate Magnetic Structure of Solar Storms

The dynamic space environment that surrounds Earth – the space our astronauts and spacecraft travel through – can be rattled by huge solar eruptions from the Sun, which spew giant clouds of magnetic energy and plasma, a hot gas of electrically charged particles, out into space. The magnetic field of these solar eruptions are difficult to predict and can interact with Earth’s magnetic fields, causing space weather effects.

VIDEO – CLICK HERE

A new tool called EEGGL – short for the Eruptive Event Generator (Gibson and Low) and pronounced “eagle” – helps map out the paths of these magnetically structured clouds, called coronal mass ejections or CMEs, before they reach Earth. EEGGL is part of a much larger new model of the corona, the Sun’s outer atmosphere, and interplanetary space, developed by a team at the University of Michigan. Built to simulate solar storms, EEGGL helps NASA study how a CME might travel through space to Earth and what magnetic configuration it will have when it arrives. The model is hosted by the Community Coordinated Modeling Center, or CCMC, at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The new model is known as a “first principles” model because its calculations are based on the fundamental physics theory that describes the event – in this case, the plasma properties and magnetic free energy, or electromagnetics, guiding a CME’s movement through space.

Such computer models can help researchers better understand how the Sun will affect near-Earth space, and potentially improve our ability to predict space weather, as is done by the U.S. National Oceanic and Atmospheric Administration.

Taking into account the magnetic structure of a CME from its initiation at the Sun could mark a big step in CME modeling; various other models initiate CMEs solely based on the kinematic properties, that is, the mass and initial velocity inferred from spacecraft observations. Incorporating the magnetic properties at CME initiation may give scientists a better idea of a CME’s magnetic structure and ultimately, how this structure influences the CME’s path through space and interaction with Earth’s magnetic fields – an important piece to the puzzle of the Sun’s dynamic behavior.

The model begins with real spacecraft observations of a CME, including the eruption’s initial speed and location on the Sun, and then projects how the CME could travel based on the fundamental laws of electromagnetics. Ultimately, it returns a series of synthetic images, which look similar to those produced of actual observations from NASA and ESA’s SOHO or NASA’s STEREO, simulating the CME’s propagation through space.

A team led by Tamas Gombosi at the University of Michigan’s Department of Climate and Space Sciences and Engineering developed the model as part of its Space Weather Modeling Framework, which is also hosted at the CCMC. All of the CCMC’s space weather models are available for use and study by researchers and the public through runs on request. In addition, EEGGL, and the model it supports, is the first “first principles” model to simulate CMEs including their magnetic structure open to the public.