Living with a Star

November 6, 2021

How Big is the Sun?

The Sun is really really big! It is difficult to get a true feel for how big it is because nothing in our daily life comes even close.
October 5, 2018

Do Solar Flares Cause Earthquakes?

We have been getting a number of questions and comments lately regarding the possible relationship between solar activity and geological activity, such as earthquakes and volcanoes, so I have decided to look into the matter in more detail. First let
November 2, 2013

A Rare Treat from the Sun, Earth and Moon – A Hybrid Eclipse

There will be a hybrid solar eclipse on Sunday November 3, 2013. This rare occurrence of an annular and total eclipse is the final eclipse event of 2013. Never look at the sun or an eclipse directly!  Eye safety during solar
February 21, 2013

A Spot with Potential

A sunspot region with potential, AR11678! Yes pun intended. This solar active region (AR for short) has emerged suddenly from under the solar photosphere (the visible “surface”) packed with magnetic potential energy and the potential for some significant flaring. It
May 6, 2012

AR11476 Comes into a Multicolored View

4 M-class Flares and More A new active region (AR11476) has been rotating into view during the beginning of May 2012. It has been producing CMEs and by May 5th it started releasing small M-class flares and lots of C-class
March 9, 2012

Geomagnetic Storm Picks Up! And AR11429 Flares Again!

      Nature never ceases to surprise and amaze. Just when it looked like the geomagnetic storm from yesterdays CME impacts had fizzled out, Earth’s magnetosphere continues its upset state. Even before the Kp index (a measure of the
March 6, 2012

4 M-class Flares in a Row

Sunspot group, AR11429, started off its journey across the Earth facing side of the Sun with several bangs. First it produced an M flare on March 2 at 17:29 UT (with a CME) then came another M flare (with a
March 5, 2012

3 Days of AR11429 – Lots of Activity

Sunspot group AR11429! Here is a look at AR11429 from Friday to today showing the 2 M-class and 1 X-class flare blasting away from the Sun. In addition to those events and their associated CMEs there is a lot of
December 15, 2011

Lovejoy’s Last Day – Unprecedented Multi-spacecraft Observations of a Comet’s Demise (Surprise filled update 12/16/2011)

UPDATE: Lovejoy survived despite most predictions to the contrary! Check out the videos below. A sungrazing comet called Lovejoy is near what will surely be its end. Sungrazers melted by the Sun is not really new. In fact, SOHO has become
November 3, 2011

Space Weather This Week: 10/27/2011 – 11/02/2011

Solar Activity Solar activity was at low to moderate levels, with occurrences of several C-class flares and three M class flares (see the list below). Quite a few slow to moderate CMEs were detected emanating from different regions of the
October 26, 2011

Anatomy of a Geomagnetic Storm – What made that great Aurora?

  Saturday, October 22, 2011, started like most any other day, lots of activity of varying size and shape was occurring on the Sun. Most people looking at the Sun that day remember the spectacular lightbulb shaped CME that occurred
September 6, 2011

M5 flare and a CME to the Side

  At 01:50 UT, sunspot group, AR11283, produced an M5 solar flare and CME (coronal mass ejection) from near the center of the solar disk. The CME  appears to be moving at an angle away from a path straight towards
August 28, 2011

Sunday CME – Activity on 28 August 2011

Well, it has been a fairly quiet couple of weeks since all the activity at the beginning of the month. Early in the morning of 28 August 2011, a small filament erupted with an associated B-class solar flare. Here is
July 4, 2011

Solar Hibernation: Much Ado About Nothing?

      A few weeks ago 3 groups of solar scientists released a joint press release at the 2011 meeting of Solar Physics Division (SPD) of the American Astronomical Society. Each group presented a unique set of solar observations,
June 7, 2011

A Spectacular Event – A Filament/Prominence Eruption to Blow Your Socks Off!

A solar flare, coronal wave, filament eruption, coronal rain & a coronal mass ejection (CME)!
May 20, 2011

Connecting the Spots (SDO Pick of the Week – May 20, 2011)

An extensive series of arcs, observed in profile, can be seen making a long distance connection between two active regions (Mar. 15-17, 2011). As SDO observed in extreme ultraviolet light, a series of magnetic field lines generated a well-defined pathway
April 1, 2011

Then and Now

SDO Pick of the Week for April 1, 2011   A side-by-side comparison of the Sun from precisely two years ago (left, from SOHO) to the present (right, from Solar Dynamics Observatory) dramatically illustrates just how active the Sun has
January 16, 2011

When the Sun has Holes We Often Get Aurora

Two coronal holes that develop over several days stand out in this image and video clip of the Sun from SDO’s AIA instrument (Jan. 9-12, 2010). In the extreme UV wavelength of 193 Angstroms, one dark coronal hole intensifies just
January 10, 2011

Solar Desktop Wallpapers

We have reached the milestone of 1000 Fans on our FaceBook page! As promised, we have been preparing a small treat for all of you as a sign of appreciation for making the TheSunToday page such a great success in
December 6, 2010

Arcing Loops

Arcing loops above an active region put on a slinky-like show for SDO, evidence of the dynamic, magnetic struggles taking place below (Nov. 28-30, 2010). Particles spiraling along magnetic field lines trace their paths as they gracefully shift and change.
December 1, 2010

Seven-Day Sun

For seven days SDO’s HMI instrument watched as a small sunspot group morphed, merged and grew into two large sunspots (Nov. 13-19, 2010) as other sunspots begin to emerge as well. We selected an image about every 15 minutes (approximately
November 8, 2010

Another Lunar Transit of the Sun Seen by SDO

As expected SDO experienced another lunar transit on November 6, 2010. This time the moon crossed the southern hemisphere moving from the south pole towards the northeast (left side) edge of the sun. The transit took about 30 minutes and
October 18, 2010

A Small Flare and Eruption from a Giant Filament

A giant filament on the sun produced a small eruption and flare.
October 11, 2010

Increased Auroral Activity Oct. 11-12 from a Halo CME Oct. 6, 2010

Around 3:30 UT on October 6, 2010 a filament erupted in the northeast part of the solar disk (upper left area). Moving at around 375 km/s (850,000 miles per hour) the CME combined with the ambient solar wind then over
October 7, 2010

A Solar Eruption as the Earth Blocks SDO’s View of the Sun

A filament erupted in the NE area of the sun. The eruption was observed by SDO and the associated Halo CME was seen by SOHO's C2 and C3 coronagraphs. SDO is currently in eclipse season so during this event the earth moved between SDO and the sun, moving across the sun for a few minutes.
October 5, 2010

The Launch of the Solar Dynamics Observatory (Part 2)

Thursday morning seemed to take longer to arrive. Expectations were certainly higher, based in no small part on the fact that most of us had flights booked to take us home later that day. Washington DC had just gotten its
October 4, 2010

A Solar Active Region’s Parting Flare

Solar sunspot group, active region (AR) 11109, is rotating out of view over the western limb of the sun. As it was moving out of the view of the earth and SDO it produced a C-class (C2.3) solar flare at
October 1, 2010

The Launch of the Solar Dynamics Observatory (Part 1)

Getting out of Washington DC was not going to be easy. The city was bracing itself for the biggest snowstorm in almost a century over the weekend. The launch of the Solar Dynamics Observatory (SDO; the first mission from NASA’s