NASA's Goddard Space Flight Center/E. Wright
This map shows the path of today's solar eclipse.
SOHO, or the Solar and Heliospheric Observatory, just celebrated 20 years in space with a main goal of learning more about the sun's activity. The spacecraft has seen some neat things, including comets, planets and unexpected solar activity. Here,based on a video recently produced by NASA
, are some of the more unusual things SOHO has witnessed.PHOTOS: The Psychedelic Anatomy of a Solar Flare
SOHO/LASCO (ESA & NASA)
Because the planets periodically pass nearby the sun from SOHO's perspective, the spacecraft can see them in its viewfinder. They look a little overexposed because they are so bright (compared with the wispy clouds of plasma in the solar wind), but they still provide a unique view of our neighbors in space. This congregation pictured here took place in 2000 and includes Venus, Mercury, Jupiter and Saturn -- as well as a famous star cluster called the Pleiades.NEWS: Ace Solar Observatory to Make 3,000th Comet Discovery
"Such congregations of planets are rare events, and they cannot be seen from the ground when close in the sky to the dazzling sun. But the LASCO C3 instrument on SOHO uses a mask to blot out direct sunlight, and it has a wide enough field of view (15 degrees) to take in the four planets in the same picture," the SOHO website wrote at the time.
Is that a snowstorm in space? No, it's actually energetic particles hitting the viewfinder of SOHO. These are caused by fast-moving protons coming from the sun, and you can see the view can get rather ... intense at times. This particular image happened in January 2012 during one of the strongest radiation storms since 2005. These storms are more frequent when the sun reaches its maximum, which last happened in roughly 2013-14.RELATED: Bye Bye Snowball - A Comet's Hellish Death Dive
NASA is interested in these storms not only because they are awesome to watch, but also to monitor their effects on Earth. Solar storms can cause blackouts in radio communications, satellites and power lines if they are strong enough. Part of SOHO's role is to provide better predictions of the sun's activity and how Earth's environment will react to it.
SOHO was not designed to look for comets, but the sun happens to be a great place to look for them. The massive gravitational attraction of the star periodically pulls comets very close to its vicinity. Most of these so-called "sungrazers" do not survive their closest approach, called perihelion, but at least we can see their remains in pictures. Comet count so far? More than 3,000.ANALYSIS: Ace Solar Observatory to Make 3,000th Comet Discovery
This is a particularly spectacular example from 2003, when Comet NEAT made a close approach while the sun was quite active. "The LASCO pictures and movies of this comet are quite out of the ordinary, with a sizeable tail and a very bright (saturated) comet nucleus," the SOHO website wrote at the time. "We even got a nice coronal mass ejection (CME) off the west limb close to perihelion time, putting the icing on the cake!"
The sun has a fairly routine cycle of activity that lasts roughly 11 years between maximum and maximum. But it's not always a clear shot as to when you're going to see a big flare. In 2003, the sun became extremely active long after its expected peak in 2001, which shows us how much more scientists have to learn.PHOTOS: Ten Mind-Blowing Solar Views from the SDO
"Some of the most intense activity that we saw was in the fall of 2003," said Joe Gurman, the U.S. project scientist for SOHO, in a NASA video posted on Twitter. "This was bit of a surprise as it was a couple of years after the maximum of the 11 year cycle."
Image: A spectacular coronal mass ejection erupts off the sun in 2003. At left is a planet.
This was a surprise discovery for SOHO. The spacecraft's observations reveal a sort of pulse that takes place during coronal mass ejections -- those particle-laden explosions from the sun. It's a neat find because it shows us more about how the inner workings of the sun create the activity that you can see in pictures of CMEs.RELATED: The Sun Rumbles With Bright Magnetic Activity
"Think of an underwater explosion: you will get water forced upwards as a great spray, but you will also get a wave on the surface of the water that travels outwards from the explosion site," SOHO wrote on an educational website. "The waves on the sun are similar, although in this case the explosion occurs just above the surface rather than below it."
Image: A 2008 solar explosion caught up close by the TRACE spacecraft after first being spotted by SOHO.
Today (March 8) the moon will pass in front of the sun, causing the first and only total solar eclipse of 2016. For skywatchers around the world, here’s how to see the eclipse and what to expect.
The eclipse will be visible across Indonesia, from the islands of Sumatra, Borneo, Sulawesi and Halmahera. A partial eclipse will be visible over southern and eastern Asia, northern and western Australia, and Hawaii. Skywatchers in the rest of the world can watch the eclipse live in a webcast hosted by the Slooh Community Observatory.
Remember, do not look directly at the sun with the naked eye or a telescope. You can use special eclipse-viewing glasses or build a pinhole projector. [March 2016 Solar Eclipse - Mostly Out to Sea | Video]
Slooh will broadcast views of the eclipse from Indonesia, along with “live feeds from several other locations along the eclipse path,” said the observatory’s website. NASA will broadcast a webcast of the eclipse as well, starting at 8 p.m. EST (0100 GMT on Wednesday, March 9) on NASA TV.
The Slooh webcast, which you can also watch the total solar eclipse on Space.com courtesy of Slooh, begins at 6 p.m. EST (2300 GMT) and goes until 9 p.m. EST (0200 GMT on Wednesday). From the location in Indonesia, the eclipse will reach totality — the point at which the moon fully blocks out the sphere of the sun — starting at 7:36 p.m. EST (0037 GMT) and lasting for only about 2 minutes.
To find out when totality occurs in different parts of the world, check out our solar eclipse reference page. At the location on the Earth known as the point of greatest duration, the sun will be fully covered by the moon for just over 4 minutes, according to Geoff Gaherty of Starry Night Education. However, this spot lies over the Pacific Ocean.
Other celestial events this week
Even for skywatchers who can’t personally observe the eclipse tomorrow, this week will offer some gorgeous celestial viewing events. Jupiter reaches opposition today, meaning Earth will pass directly between the mighty planet and the sun. As a result, Jupiter will rise just as the sun is setting, remain visible through the night and set when the sun rises.
Jupiter is currently the brightest object in the night sky (with the exception of the moon and the International Space Station), so it is easily observable with the naked eye. But a good pair of binoculars or a small telescope will also reveal some of the gas giant’s moons. Mars and Saturn are also on display this month.
And if that isn’t enough to satiate your skywatching appetite, Slooh will host another webcast on Wednesday night to track the journey of the 100-foot-wide (30.4 meters) asteroid 2013 TX68. You can also watch the webcast here on Space.com, courtesy of Slooh.
The asteroid made a close approach to Earth yesterday (March 7), at 8:42 a.m. EST (1342 GMT), coming to within 2,542,960 miles (4,092,497 kilometers) of Earth’s surface, according to the Minor Planet Center, as reported on Slooh’s website. However, even at its closest point, the asteroid was not visible with the naked eye, or even with a good telescope, said scientists at NASA’s Jet Propulsion Laboratory.
“Slooh will live-stream the event from its flagship Canary Islands Observatory, which will be accompanied by discussions led by Slooh astronomer Eric Edelman and scientist Dr. Mark Boslough, an expert on planetary impacts and global catastrophes and frequent participant on many science TV documentaries,” said the Slooh website.