http://soho.nascom.nasa.gov/ Solar and Heliospheric Observatory en-us http://soho.nascom.nasa.gov/pickoftheweek/old/19may2008/ The Pleiades star cluster (also known as the Seven Sisters and Messier 45) and Venus are gliding behind the Sun and moving towards each other in a conjunction or visual meeting... http://soho.nascom.nasa.gov/rss/item0059 http://soho.nascom.nasa.gov/pickoftheweek/old/16may2008/ Over a period of almost two days (May 9-10, 2008) numerous prominences and extensions danced above the Sun's edge as seen in... http://soho.nascom.nasa.gov/rss/item0058 http://soho.nascom.nasa.gov/pickoftheweek/old/02may2008/ SOHO's EIT telescope observed a wave streak across part of the solar surface when a (moderate) flare erupted on... http://soho.nascom.nasa.gov/rss/item0057 http://soho.nascom.nasa.gov/pickoftheweek/old/25apr2008/ This STEREO image and video clip of the Sun in extreme ultraviolet light (April 18-19, 2008) showcase a group of active regions near the Sun's left edge over about 40 hours... http://soho.nascom.nasa.gov/rss/item0056 http://soho.nascom.nasa.gov/pickoftheweek/old/18apr2008/ This movie shows an exceptionally large prominence eruption on the Sun on April 9, 2008, as seen from the STEREO Ahead spacecraft. Just above the solar surface, the relatively cool prominence... http://soho.nascom.nasa.gov/rss/item0055 http://soho.nascom.nasa.gov/hotshots/2008_04_18/ Data from SOHO's VIRGO instrument show clearly that powerful starquakes ripple around the Sun... http://soho.nascom.nasa.gov/rss/item0054 http://soho.nascom.nasa.gov/pickoftheweek/old/11apr2008/ A close-up of the Sun from the STEREO (Ahead) spacecraft showing a pair of active regions (that appear as brighter regions) with some interesting activity over a two-day period... http://soho.nascom.nasa.gov/rss/item0053 http://soho.nascom.nasa.gov/pickoftheweek/old/04apr2008/ On March 25, 2008 STEREO observed its first M-class (medium-sized) solar flare, which was also associated with a coronal mass ejection. Flares are intense... http://soho.nascom.nasa.gov/rss/item0052 http://soho.nascom.nasa.gov/pickoftheweek/old/21mar2008/ The STEREO (Ahead) spacecraft watched closely as a solar prominence gracefully rose up above the surface, spun around a little, formed an arc, and eventually dissipated along... http://soho.nascom.nasa.gov/rss/item0051 http://soho.nascom.nasa.gov/pickoftheweek/old/21mar2008/ The STEREO (Ahead) spacecraft was watching in extreme UV light (March 15, 2008) as a small active region emerged from beneath the Sun's surface... http://soho.nascom.nasa.gov/rss/item0050 http://soho.nascom.nasa.gov/pickoftheweek/old/14mar2008/ SOHO has spotted an expansive coronal that has apparently returned for a repeat performance right on schedule. This darker area has just crossed the centerline of the Sun and will be streaming solar wind towards Earth... http://soho.nascom.nasa.gov/rss/item0049 http://soho.nascom.nasa.gov/pickoftheweek/old/07mar2008/ Just in case our web visitors did not realize it, almost every SOHO image is now available online, all the way back to 1996... http://soho.nascom.nasa.gov/rss/item0048 http://soho.nascom.nasa.gov/pickoftheweek/old/29feb2008/ Using two STEREO instruments that view the Sun in extreme UV light, we can combine frames taken at about the same time and see features from both. The focus of interest here is an active region coming around the edge... http://soho.nascom.nasa.gov/rss/item0047 http://soho.nascom.nasa.gov/outreach/past/Suntrek/ Sun|trek is an exciting new website for school students and teachers about the Sun and its effect on the Earth. Sun|trek has been motivated and inspired by the fantastic images and movies of the Sun... http://soho.nascom.nasa.gov/rss/item0046 http://soho.nascom.nasa.gov/pickoftheweek/old/22feb2008/ This graphic suggests how we can take a closer look at the image sizes that can be obtained by three major solar missions, from SOHO to STEREO, and then to SDO (Solar Dynamics Observatory). We can begin to understand the substantial increase... http://soho.nascom.nasa.gov/rss/item0045 http://soho.nascom.nasa.gov/pickoftheweek/old/15feb2008/ A substantial coronal hole can be seen (below center and extending to the right) in this image by STEREO. Coronal holes appear as darker areas when viewed in this extreme... http://soho.nascom.nasa.gov/rss/item0044 http://soho.nascom.nasa.gov/pickoftheweek/old/08feb2008/ On Jan. 30, 2008 STEREO observed two different kinds of spin-offs from the Sun, called eruptive prominences, over a period of several hours. The first one is harder... http://soho.nascom.nasa.gov/rss/item0043 http://soho.nascom.nasa.gov/pickoftheweek/old/01feb2008/ The Sun blew out a coronal mass ejection (CME) that resembled an almost perfectly shaped smoke ring... http://soho.nascom.nasa.gov/rss/item0042 http://soho.nascom.nasa.gov/pickoftheweek/old/25jan2008/ Beginning late on January 16 2008 the asteroid Vesta appeared in the STEREO SECCHI COR2-A ("Ahead" spacecraft) images. Although a fairly small, whitish dot, it can be picked... http://soho.nascom.nasa.gov/rss/item0041 http://soho.nascom.nasa.gov/pickoftheweek/old/18jan2008/ The two STEREO spacecraft have been slowly separating over most of the mission, so that now they are 44 degrees apart as of Jan. 8, 2008. They will continue to separate as the... http://soho.nascom.nasa.gov/rss/item0040 http://soho.nascom.nasa.gov/pickoftheweek/old/09jan2008/ Which magnetic polarity leads and which follows in solar active regions alternates with each, roughly 11.1 year solar activity cycle... http://soho.nascom.nasa.gov/rss/item0039 http://soho.nascom.nasa.gov/pickoftheweek/old/05jan2008/ As 2007 ended and 2008 began, the Sun blasted out two coronal mass ejections (CMEs) on Dec. 31, 2007 and Jan. 2, 2008, perhaps in celebration of the New Year. At any rate, over the span of 3 days, two separate CMEs blew out... http://soho.nascom.nasa.gov/rss/item0038 http://soho.nascom.nasa.gov/pickoftheweek/old/28dec2007/ As we approach the end of another year of solar observing, it might be worth noting the record of SOHO's longevity. We can compare solar images from the same instrument taken the same day, but 11 years apart... http://soho.nascom.nasa.gov/rss/item0037 http://soho.nascom.nasa.gov/pickoftheweek/old/21dec2007/ SOHO has observed what may be the first indication of a "reversed" magnetic polarity region when compared to the current solar cycle, something scientists consider to be a crucial indicator that...... http://soho.nascom.nasa.gov/rss/item0036 http://soho.nascom.nasa.gov/gallery/Movies/flares.html#Halloween Many SOHO fans keep have been asking for hi-resolution movies of the 2004 Halloween storms... http://soho.nascom.nasa.gov/rss/item0035 http://soho.nascom.nasa.gov/outreach/past/Montshire/ The museum houses two floors of hands-on science exhibits highlighting physical and natural history and includes 110 acres of trails and... http://soho.nascom.nasa.gov/rss/item0034 http://soho.nascom.nasa.gov/pickoftheweek/old/14dec2007/ One of the STEREO spacecraft (Ahead) caught an enourmous wave as it rippled across the most of the Sun... http://soho.nascom.nasa.gov/rss/item0033 http://soho.nascom.nasa.gov/pickoftheweek/old/07dec2007/ Over a five-day stretch (Nov. 30 - Dec. 4, 2007) SOHO observed two remarkably similar coronal mass ejections (CMEs). The first one blew out to the right from the Sun as a... http://soho.nascom.nasa.gov/rss/item0032 http://antwrp.gsfc.nasa.gov/apod/ap071203.html Every eleven years, our Sun goes through a solar cycle. A complete solar cycle has now been imaged by the sun-orbiting SOHO spacecraft, celebrating the 12th anniversary of its launch ... http://soho.nascom.nasa.gov/rss/item0031 http://soho.nascom.nasa.gov/hotshots/2007_12_02/ SOHO celebrates its 12th launch anniversary on December 2 and has now observed almost a full solar cycle... http://soho.nascom.nasa.gov/rss/item0030 http://soho.nascom.nasa.gov/pickoftheweek/old/30nov2007/ Solar study spacecraft from a number of missions observe the Sun in various wavelengths of light every day. This representative collage... http://soho.nascom.nasa.gov/rss/item0029 http://soho.nascom.nasa.gov/pickoftheweek/old/21nov2007/ STEREO captured three differently shaped CMEs (coronal mass ejections) blasting out from the Sun over a three-day span... http://soho.nascom.nasa.gov/rss/item0028 http://soho.nascom.nasa.gov/pickoftheweek/old/16nov2007/ A well-positioned and substantial coronal hole can be seen (right of center) in this (November14, 2007) image by SOHO. Coronal holes appear as the dark areas when viewed... http://soho.nascom.nasa.gov/rss/item0027 http://soho.nascom.nasa.gov/pickoftheweek/old/09nov2007/ The STEREO spacecraft observed this small prominence rising up from the Sun's surface, twisting around, and subsiding over... http://soho.nascom.nasa.gov/rss/item0026 http://soho.nascom.nasa.gov/pickoftheweek/old/02nov2007/ This week SOHO offers a comparison of solar observations from the same instrument a solar cycle: two EIT 304 Angstrom images (in extreme ultraviolet light) across exactly eleven years... http://soho.nascom.nasa.gov/rss/item0025 http://soho.nascom.nasa.gov/pickoftheweek/old/26oct2007/ Actually, no. This is what we might call a "manufactured" 3D Sun. It was produced by combining two SOHO images from its EIT 195 instrument that were taken 10.5 hours apart... http://soho.nascom.nasa.gov/rss/item0024 http://soho.nascom.nasa.gov/pickoftheweek/old/12oct2007/ For the first time we are featuring an observation from one of the STEREO coronagraphs. This COR2 still and video clip show a modest coronal mass ejection blasting into space... http://soho.nascom.nasa.gov/rss/item0023 http://soho.nascom.nasa.gov/pickoftheweek/old/05oct2007/ Many people ask if we are at solar minimum yet and how do we know when we are... http://soho.nascom.nasa.gov/rss/item0022 http://soho.nascom.nasa.gov/pickoftheweek/old/28sep2007/ One of the STEREO spacecraft (Behind) observed an elongated loop that emerges and then disperses over a two-day period... http://soho.nascom.nasa.gov/rss/item0021 http://soho.nascom.nasa.gov/hotshots/2007_09_24/ It is nothing new for the Solar and Heliospheric Observatory (SOHO) to discover another comet - it has already found more than 1,350. The latest SOHO comet, discovered by the LASCO coronagraph, is a bit different however, because SOHO had already "discovered" it twice before... http://soho.nascom.nasa.gov/rss/item0020 http://soho.nascom.nasa.gov/pickoftheweek/old/21sep2007/ SOHO observed (September 19, 2007) a wide coronal hole that appeared as the large dark area when viewed in this wavelength (284 Angstrom) of extreme ultraviolet light and in X-rays... http://soho.nascom.nasa.gov/rss/item0019 http://soho.nascom.nasa.gov/pickoftheweek/old/14sep2007/ With their 2048 x 2048 frame size and images as often as every 2.5 minutes, STEREO images in the extreme ultraviolet wavelength provides us with the opportunity to pick out any part of the Sun and zoom in for a much closer look...... http://soho.nascom.nasa.gov/rss/item0018 http://soho.nascom.nasa.gov/pickoftheweek/old/07sep2007/ When the Sun is in its quiet period as it is now, it often presents some very distinctive coronal structures that can be observed with SOHO's coronagraphs... http://soho.nascom.nasa.gov/rss/item0017 http://soho.nascom.nasa.gov/pickoftheweek/old/31aug2007/ A close-up of an active region of the Sun from STEREO's Ahead spacecraft in extreme ultraviolet revealed an interesting, yet subtle, phenomenon... http://soho.nascom.nasa.gov/rss/item0016 http://soho.nascom.nasa.gov/pickoftheweek/old/22aug2007/ This week STEREO observed a nice gathering of solar prominences in profile as they twisted, stretched and floated just above the solar surface... http://soho.nascom.nasa.gov/rss/item0015 http://soho.nascom.nasa.gov/pickoftheweek/old/15aug2007/ Over a period of four days (July 27 - 31, 2007) two active regions can be seen by SOHO communicating with each other magnetically.... http://soho.nascom.nasa.gov/rss/item0014.5 http://soho.nascom.nasa.gov/outreach/ The Penn State Department of Astronomy and strophysics is a dynamic place with active research programs in most observational and theoretical areas of astronomy... http://soho.nascom.nasa.gov/rss/item0014 http://soho.nascom.nasa.gov/pickoftheweek/old/09aug2007/ A close up view of the top of the Sun as seen in profile shows thousands of little spurts, like small blow torches, shooting out all over the Sun. The movie shows just an average day's worth of this kind of activity... http://soho.nascom.nasa.gov/rss/item0013 http://soho.nascom.nasa.gov/pickoftheweek/old/26jul2007/ While it may look otherworldly, this is still just the Sun and its environs as seen from SOHO (July 24, 2007). By combining these three views onto one image we can try to suggest SOHO's expansive capacity to see... http://soho.nascom.nasa.gov/rss/item0012 http://soho.nascom.nasa.gov/pickoftheweek/old/19jul2007/ In real estate the three most important words are "Location, Location, Location...". When it comes to solar observations, we do in fact have three spacecraft (STEREO Behind, SOHO, and STEREO Ahead) in three different locations to give us a much wider perspective than any one spacecraft could do... http://soho.nascom.nasa.gov/rss/item0011 http://soho.nascom.nasa.gov/pickoftheweek/old/12jul2007/ Over a four-day period (July 7-11, 2007) of watching the Sun's atmosphere with SOHO's C2 coronagraph, we observed a sputtering outflow of particles from an... http://soho.nascom.nasa.gov/rss/item0010 http://soho.nascom.nasa.gov/pickoftheweek/old/05jul2007/ Using STEREO (Ahead) spacecraft's highest resolution frames (2048?2048 pixels per frame), we can zoom in a lot on areas of interest and still maintain good visual acuity. Over 34 hours (June 29-30, 2007), we zoom in on a pair of active regions and observe numerous instances of flaring activity... http://soho.nascom.nasa.gov/rss/item0009 http://soho.nascom.nasa.gov/pickoftheweek/old/29jun2007/ SOHO is keeping a close eye on a good-sized active region that is rotating into view. The video clip covers 36 hours (June 27-28, 2007) as the bright glow and arcs above the solar surface appear before we can actually see a sunspot on the surface... http://soho.nascom.nasa.gov/rss/item0008 http://soho.nascom.nasa.gov/pickoftheweek/old/22jun2007/ The main noteworthy feature on the Sun this past week is the one, dark, coronal hole that we watched as it rotated to the Sun's center over three days (June 17-19, 2007). Anyone who inspects the movie carefully will note that there were no ... http://soho.nascom.nasa.gov/rss/item0007 http://soho.nascom.nasa.gov/hotshots/2007_05_25/ A new method to forecast solar radiation storms has been developed, based on data from the COSTEP instrument onboard SOHO. This novel technique offers as much as one hour advance warning, giving astronauts time to seek shelter and ground controllers time to safeguard their satellites when a storm is approaching... http://soho.nascom.nasa.gov/rss/item0006 http://soho.nascom.nasa.gov/pickoftheweek/ SOHO had a ring-side seat to watch as a sun-grazing comet swept by the Sun on June 8, 2007. With its tail stretching far out behind it, it was one of the brightest sun-grazers that we have seen... http://soho.nascom.nasa.gov/rss/item0005 http://soho.nascom.nasa.gov/pickoftheweek/ The main noteworthy feature on the Sun this past week is the one, dark, coronal hole that we watched as it rotated to the Sun's center over three days (June 17-19, 2007). Anyone who inspects the movie carefully will note that there were... http://soho.nascom.nasa.gov/rss/item0004 http://soho.esac.esa.int/ NOTICE: On July 3rd, 2007 the SOHO website will be unavailable due to scheduled network maintenance. The outage will affect a variety of services including access to the SOHO Archive Catalog, SOLARSOFT distribution updates and image updates to the SOHO screen-saver. Please use the European mirror site instead. We are sorry for the inconvenience. http://soho.nascom.nasa.gov/rss/item0003 http://soho.nascom.nasa.gov/pickoftheweek/ SOHO is keeping a close eye on a good-sized active region that is rotating into view. The video clip covers 36 hours (June 27-28, 2007) as the bright glow and arcs above the solar surface appear before... http://soho.nascom.nasa.gov/rss/item0002