The Atmospheric Imaging Assembly on NASA's Solar Dynamics Observatory captured its 100 millionth image of the sun on Jan. 19, 2015. The dark areas at the bottom and the top of the image are coronal holes -- areas of less dense gas, where solar material has flowed away from the sun. Read more
The 2014 spring eclipse season NASA's Solar Dynamics Observatory begins Feb. 27, 2014. These seasons - a time when Earth blocks SDO's view of the sun for a period of time each day - last around three weeks and happen twice a year near the equinoxes. The eclipses are fairly short near the beginning and end of the season but ramp up to 72 minutes in the middle. Read more
On June 5, 2012 at 22:03 UT, the planet Venus will do something it has done only seven times since the invention of the telescope: cross in front of the sun. This transit is among the rarest of planetary alignments and it has an odd cycle. Two such Venus transits always occur within eight years of each other and then there is a break of either 105 or 121 years before it happens again. NASA's Solar Dynamics Observatory (SDO) will be watching the June 2012 transit to help calibrate its instruments as well as to learn more about Venus's atmosphere. Since the points at which Venus will first touch and later leave the sun is known down to minute detail, SDO can use this information to make sure its images are oriented to true solar North. Orienting instruments is a constant adjustment game for telescopes in space, since their original position can be shifted during launch. Various calibrations throughout the two years SDO has been in space have left the scientists confident that the instruments are highly accurate, but making sure that Venus appears in the SDO images exactly where scientists know it should be will help make sure SDO's orientation is accurate to within a tenth of a pixel. Read more
In April of 2010, NASA's Solar Dynamics Observatory (SDO) released its first images, an event known for any telescope as "first light." Since then SDO has continually observed the ever-changing sun on quiet days and explosive ones: there have been more than 1000 solar outbursts since SDO sent back its first pictures of the sun, including flares, coronal mass ejections (CMEs), and the release of energetic particles that can be flung to the farthest reaches of the solar system. Here we describe some of the highlights of SDO science and observations during its second year. Read more
Partial eclipse of sun on the SDO satellite (Feb 21, 2012)
Credit: VIDEOVAX
The moon hides part of the solar disk. The SDO satellite is in geosynchronous orbit around the Earth. Given that today is the new moon, it explains why we can see a partial eclipse of the sun since the satellite's instruments SDO. Knowing that the satellite moves from west to east around the Earth at about 42,200 kms (relative to the center of the Earth), and depending on the apparent motion of the Moon on the images, we can infer that the satellite was approximately over the american continent, between 13:00 and 15:00 UT.
April 21, 2011 marks the one-year anniversary of when the Solar Dynamics Observatory (SDO) captured its first images, an event referred to for all telescopes as "first light". In the last year, the sun has gone from one of its most dormant periods in years to strong activity. SDO has captured every moment with a level of detail never-before possible. The mission has returned unprecedented images of solar flares, giant loops called prominence eruptions, and the early stages of coronal mass ejections (CMEs). We would like you to vote for your favourite video from a collection that spans SDO's first year of science observations. The voting closes on May 5, 2011. Read more
On February 11, 2010, at 10:23 in the morning, NASA's Solar Dynamics Observatory (SDO) launched into space on an Atlas rocket from Cape Canaveral. A year later, SDO has sent back millions of stunning images of the sun and a host of new data to help us understand the complex star at the heart of our solar system. Read more
The SDO JSOC has experienced a disk controller failure. The near-real-time images will not be produced until the controller can be replaced. Stay tuned for updates.
Title: HMI: First results Authors: Rebecca Centeno (1), Steve Tomczyk (1), Juan Manuel Borrero (2), Sebastien Couvidat (3), Keiji Hayashi (3), Todd Hoeksema (3), Yang Liu (3), Jesper Schou (3) ((1) High Altitude Observatory, Boulder, CO, (2) Kiepenheuer-Institut fur Sonnenphysik, Freiburg, Germany, (3) Stanford University, Stanford, CA)
The Helioseismic and Magnetic Imager (HMI) has just started producing data that will help determine what the sources and mechanisms of variability in the Sun's interior are. The instrument measures the Doppler shift and the polarisation of the Fe I 6173 A line, on the entire solar disk at a relatively-high cadence, in order to study the oscillations and the evolution of the full vector magnetic field of the solar Photosphere. After the data are properly calibrated, they are given to a Milne-Eddington inversion code (VFISV, Borrero et al. 2010) whose purpose is to infer certain aspects of the physical conditions in the Sun's Photosphere, such as the full 3-D topology of the magnetic field and the line-of-sight velocity at the solar surface. We will briefly describe the characteristics of the inversion code, its advantages and limitations --both in the context of the model atmosphere and the actual nature of the data--, and other aspects of its performance on such a remarkable data load. Also, a cross-comparison with near-simultaneous maps from the Spectro-Polarimeter (SP) onboard Hinode will be made.