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Solar Flares and CME’s: Coronal Mass Ejections 

A Solar Flare is a sudden flash of brightness observed over the Sun’s surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy. They are often, but not always, followed by a colossal coronal mass ejection. The flare ejects clouds of electrons, ions, and atoms through the corona of the sun into space. These clouds typically reach Earth a day or two after the event. The term is also used to refer to similar phenomena in other stars, where the term stellar flare applies.

A Coronal Mass Ejection (CME) is a massive burst of gas and magnetic field arising from the solar corona and being released into the solar wind, as observed in a coronagraph. Coronal mass ejections are often associated with other forms of solar activity, most notably solar flares or filament eruptions, but a broadly accepted theoretical understanding of these relationships has not been established. 

CMEs most often originate from active regions on the Sun’s surface, such as groupings of sunspots associated with frequent flares. Near solar maxima, the Sun produces about three CMEs every day, whereas near solar minima, there is about one CME every five days.

Giffed by: rudescience  From: This video by nasa

Kamikaze Comet Loses its Head

Kamikaze Comet Loses its Head

Headless comet D1 SOHO photographed in evening twilight on Feb. 28. The comet survived its Feb. 19 perihelion passage but soon after crumbled apart to form a cloud of glowing dust. Credit: Michael Jaeger

Like coins, most comet have both heads and tails. Occasionally, during a close passage of the Sun, a comet’s head will be greatly diminished yet still retain a classic cometary outline. Rarely…

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The end is nigh, Engadget readers: a triumvirate of celestial events is happening simultaneously. Okay, that might be a bit of an overstatement, but until we hit the other side of today’s supermoon, spring equinox (yay!) and total solar eclipse, we just won’t know. As The Wall Street Journal tells it, this sort of thing is “extremely unusual.” Total solar eclipses — where the moon plays middleman and blocks the sun from our view — happen about once every year-and-a-half. Supermoons and the equinox? A handful of times per year and once annually, respectively.

Should you want to witness the full effect you’ll need to either be in the northern reaches of Europe or the Arctic, with the Faroe and Svalbard Islands sitting in the “path of totality” where the moon will block 100 percent of the sun. Certain areas of Britain will go dark for a few hours around 4:30 AM Eastern Time, too, but only 85 percent of the sun’ll be blocked instead of 100.

A GIF from NASA depicting the path of today’s solar eclipse

Not only do these types of eclipses look pretty neat, they serve as a great opportunity for scientists to study our star as well. For example, space-based coronagraphs (telescopes that spot things super close to the Sun by replicating solar eclipses) can’t show Sol’s hotter, inner atmosphere — that’s only visible during the real mccoy here on Earth. NASA has a whole slew of other solar eclipse facts so make sure to check ‘em out while you still can.

“A solar eclipse, the cosmic ballet goes on.”
“Does anyone wanna switch seats?” #eclipse2015 pic.twitter.com/tsake9ULLF

– SimpsonsQOTD (@SimpsonsQOTD) March 20, 2015

[Image credit: Shutterstock]

Filed under: Science, Alt

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Source: NASA, The Wall Street Journal Follow @DailyTechWhip

Source: Engadget - Read the full article here

The post Total solar eclipse coincides with supermoon and spring equinox appeared first on Daily Tech Whip.

Two recent reports from two Science and Technology Definition Teams from NASA’s astrophysics division have detailed proposals to detect extrasolar planets orbiting nearby stars. One report studied a concept based on a telescope with an internal coronagraph capable of generating the ultra-high contrast images needed for planet detection. The other evaluated the feasibility of flying a pair of spacecraft in formation — a telescope and an external starshade.

(via We’re one step closer to finding new Earth-like planets | ideas.ted.com)

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Massive Plasma Filament Eruption | GoToSpace - April 28, 2015
Massive Plasma Filament Eruption | Go To Space - April 28, 2015 http://sidc.oma.be/ SDO/AIA and H-alpha GONG images indicate the eruption of the extended filament, which was stretching from S05E10 to N40E80, starting around 11:00UT (April 28). The eruption was triggered by the eruption of a filament that was located south of this large one. The eruption was followed by a Hyder flare. Due to the location of the eruption, a halo CME is to be expected. The first coronagraphic data of SOHO/LASCO do indicate the occurrence of a CME, but more images are required for further analysis of its characteristics and estimate the effects on Earth’s environment. Website under construction: http://ift.tt/1bbk3F6 Go To Space | GoToSpace | Plasma Filament Eruption | Massive CME

New Post has been published on http://earthchangesmedia.com/cme-possibly-earth-directed

CME, Possibly Earth-Directed

A magnetic filament snaking around the Sun’s southern hemisphere erupted on May 3rd. The blast did not create a pulse of electromagnetic radiation (i.e., a solar flare), but it did hurl a CME into space. The Solar and Heliospheric Observatory recorded the expanding cloud.

Although the CME is not moving directly along the sun-Earth line, it might still be geoeffective. A glancing blow is possible on May 5th or 6th. NOAA analysts are evaluating this possibility as they receive additional coronagraph data. Stay tuned for updates in the hours ahead.

Related posts:

So yesterday was a big day for my site, TheGentlemanRacer.com which has been growing at a meteoric pace the last two years… today we hit over 1 million unique visitors in under 6 months, more than we have done in any year previously. Since I refocused the site two years ago into a general mens/automotive lifestyle website, the site has takeing on a life of it’s own. It has been linked to by Road & Track, Hot Rod Magazine, Popular Mechanics and even GQ as a source. We have worked with brands like TSOVET Watches, Ford Motor Company, Fiat, Coach, Cragar Wheels, BRM Coronagraphs, and many others on fashion editorial and more.It has even spawned a limited edition annual print magazine that chronicles our top stories from the previous year. The site covers travel, model features, fashion and much more. It has become it’s own brand, in an many ways my identity, people often come up to me at events and say “Hey you’re The Gentleman Racer” to which I always feel a little embarrassed. But the coolest thing is when someone takes the time to let me know that a story inspired them to build car, take a trip, or launch their own website.

The best part about this site is I have been able to share a number of my adventures with our readers, from working with an NGO in Nicaragua to driving across the Island of Java, to my latest project, attempting to build a classic rally car and race across Mexico.

We have reached people in over 170 countries, with 63% of our audience being in the USA.

What started out as a platform for my photography and stories has become a site that a lot of people enjoy and I am always humbled that I get the opportunity to do the things I love.

#thegentlemanracer #mikesatterfield #blogger #fblogger #travelblogger #lablogger #carblogger #fashionblogger #menswear #racing #ranchocucamonga (at thegentlemanracer.com)

[ Authors ]
Alain Leger, Denis Defrere, Fabien Malbet, Lucas Labadie, Olivier Absil
[ Abstract ]
We present an analytic model to estimate the capabilities of space missions dedicated to the search for biosignatures in the atmosphere of rocky planets located in the habitable zone of nearby stars. Relations between performance and mission parameters such as mirror diameter, distance to targets, and radius of planets, are obtained. Two types of instruments are considered: coronagraphs observing in the visible, and nulling interferometers in the thermal infrared. Missions considered are: single-pupil coronagraphs with a 2.4 m primary mirror, and formation flying interferometers with 4 x 0.75 m collecting mirrors. The numbers of accessible planets are calculated as a function of {\eta}earth. When Kepler gives its final estimation for {\eta}earth, the model will permit a precise assessment of the potential of each instrument. Based on current estimations, {\eta}earth = 10% around FGK stars and 50% around M stars, the coronagraph could study in spectroscopy only ~1.5 relevant planets, and the interferometer ~14.0. These numbers are obtained under the major hypothesis that the exozodiacal light around the target stars is low enough for each instrument. In both cases, a prior detection of planets is assumed and a target list established. For the long-term future, building both types of spectroscopic instruments, and using them on the same targets, will be the optimal solution because they provide complementary information. But as a first affordable space mission, the interferometer looks the more promising in term of biosignature harvest.

[ Authors ]
Sasha Hinkley, Brendan P. Bowler, Arthur Vigan, Kimberly M. Aller, Michael C. Liu, Dimitri Mawet, Elisabeth Matthews, Zahed Wahhaj, Stefan Kraus, Isabelle Baraffe, Gilles Chabrier
[ Abstract ]
We present 0.95-1.80 $\mu$m spectroscopy of the $\sim$12-27 $M_{\rm Jup}$ companion orbiting the faint ($R$$\sim$13.6), young ($\sim$120 Myr) M-dwarf 2MASS J01225093–2439505 (“2M0122–2439 B”) at 1.5 arcsecond separation (50 AU). Our coronagraphic long-slit spectroscopy was obtained with the new high contrast imaging platform VLT-SPHERE during Science Verification. The unique long-slit capability of SPHERE enables spectral resolution an order of magnitude higher than other extreme AO exoplanet imaging instruments. With a low mass, cool temperature, and very red colors, 2M0122-2439 B occupies a particularly important region of the substellar color-magnitude diagram by bridging the warm directly imaged hot planets with late-M/early-L spectral types (e.g. $\beta$ Pic b and ROXs 42Bb) and the cooler, dusty objects near the L/T transition (e.g. HR 8799bcde and 2MASS 1207b). We fit BT-Settl atmospheric models to our $R$$\approx$350 spectrum and find $T_{\rm eff}$=1600$\pm$100 K and $\log(g)$=4.5$\pm$0.5 dex. Visual analysis of our 2M0122-2439 B spectrum suggests a spectral type L3-L4, and we resolve shallow $J$-band alkali lines, confirming its low gravity and youth. Specifically, we use the Allers & Liu (2013) spectral indices to quantitatively measure the strength of the FeH, VO, KI, spectral features, as well as the overall $H$-band shape. Using these indices, along with the visual spectral type analysis, we classify 2M0122-2439 B as an intermediate gravity (INT-G) object with spectral type L3.7$\pm$1.0.

[ Authors ]
Richard G. Lyon, Brian A. Hicks, Mark Clampin, Peter Petrone III
[ Abstract ]
The search for life via characterization of earth-like planets in the habitable zone is one of the key scientific objectives in Astronomy. We describe a new phase-occulting (PO) interferometric nulling coronagraphy (NC) approach. The PO-NC approach employs beamwalk and freeform optical surfaces internal to the interferometer cavity to introduce a radially dependent plate scale difference between each interferometer arm (optical path) that nulls the central star at high contrast while transmitting the off-axis field. The design is readily implemented on segmented-mirror telescope architectures, utilizing a single nulling interferometer to achieve high throughput, a small inner working angle (IWA), sixth-order or higher starlight suppression, and full off-axis discovery space, a combination of features that other coronagraph designs generally must trade. Unlike previous NC approaches, the PO-NC approach does not require pupil shearing; this increases throughput and renders it less sensitive to on-axis common-mode telescope errors, permitting relief of the observatory stability required to achieve contrast levels of $\leq10^{-10}$. Observatory operations are also simplified by removing the need for multiple telescope rolls and shears to construct a high contrast image. The design goals for a PO nuller are similar to other coronagraphs intended for direct detection of habitable zone (HZ) exoEarth signal: contrasts on the order of $10^{-10}$ at an IWA of $\leq3\lambda/D$ over $\geq10$% bandpass with a large ($>10$~m) segmented aperture space-telescope operating in visible and near infrared bands. This work presents an introduction to the PO nulling coronagraphy approach based on its Visible Nulling Coronagraph (VNC) heritage and relation to the radial shearing interferometer.