Archive for category News
Some of you may have noticed that recent LASCO C2 images are upside down. You can notice this quite easily, as the streamer belts in LASCO C2 do not line up with the streamer belts in LASCO C3. This is due to an error in the way we write out LASCO C2 images. We are diagnosing the problem and will rewrite the affected images shortly. This in itself will be delayed due to the fact that the machine which writes out new LASCO C2 and C3 images will be offline for a couple of days. We apologize for the interruption to our service in the delivery of good quality new and recent LASCO images. Older LASCO images are unaffected, as are HMI and AIA images.
Today the Moon is passing across the field of view of AIA on board SDO. AIA sees this as a partial obscuration of the disk of the Sun. If you look at an AIA image near 15:00 UTC (March 04, 2011) you can clearly see that a big round object – our Moon – is blocking a portion of the solar disk, and some off disk-emission.
If you zoom in to the image, you can see that the edge is not perfectly circular. Those are mountains and valleys on the Moon seen in silhouette.
This partial eclipse of the Sun as seen by SDO was expected, since we know the orbits of SDO, AIA, the Sun and the Moon. You can find out more about the eclipses SDO will see (and has seen) by checking out the SDO operations calendar.
As well as being stunning displays of orbital mechanics, partial eclipses of the Sun by the Moon are also very useful in helping us understand the data we are taking with AIA. If you look closely at where the disk of the Moon meets the Sun, you can see a little bit of color is in the dark disk of the Moon. Since we know that the Moon does not emit radiation (and it is not transparent!), the light causing that little bit of color must have come from the Sun. The only way that light could appear to have come from the Moon is due to slight imperfections in the telescope. By measuring how much light leaks from the bits of the image where the Sun is, over to the bits of the image where the Moon is, we can characterize the imperfections in the telescope. And once we have done that, we can use that to improve the images by enhancing the image to take out the effects of the telescope imperfections.
The latest JHelioviewer update adds support for SDO/HMI data and features a new contrast filter, as well as an improved plugin to access the Heliophysics Event Knowledgebase (HEK).
Thanks to NASA’s Solar Dynamics Observatory mission, the Helioviewer server, hosted in the Solar Data Analysis Center at the Goddard Space Flight Center, Maryland, USA, has acquired and made operational an additional 15TB of storage. This will allow us to maintain through the coming year, the same level of service of Atmospheric Imaging Assembly (AIA) and other images that we already provide through the Helioviewer.org and JHelioviewer browse clients. This new storage will allow us to keep all the images we already have, plus new images from the upcoming year, online and available for our users to browse as they please. As always, we welcome any comments on how we may improve our service, and we look forward to what the Sun will bring us in 2011!
Many institutions host many different kinds of image data, either from observations or from simulations. I have put instructions on how to convert image data to a format the Helioviewer Project uses on our wiki page. The wiki is where we keep our must up-to-date instructions on the installation and use of all the software we are developing.
Contact me if you encounter any problem with the JP2Gen instructions , or with implementing JP2Gen on your local system (or any other part of the wiki). I’d be very happy to get your feedback!
Some people were aware that our server had a hardware issue shortly before the Fifth Solar Image Processing Workshop (http://sipworkv.sipwork.org/). Bad timing. But now the good news – we have it back, and we are filling it with JP2 images. We should be heading back to full operations on our newly repaired server very soon.