July 4, 2021

So Far Away: Aphelion 2021

This farthest point occurs July 5, 2021, at 6:27 pm EDT or 10:27 pm UTC. At that time the distance from Earth’s center to the Sun’s center will be 94,510,886 miles (152,100,527 km).
June 20, 2021
June & December Solstice Comparison

Time for a Change of Seasons – 2021 June Solstice

The June Solstice for 2021 occurs on June 21st at 3:22 UTC (11:32 pm EDT on June 20th). It is the beginning of summer for the northern hemisphere and winter for the southern hemisphere.
February 8, 2021

Happy 1st Anniversary Solar Orbiter – The Science is Just Beginning

February 9, 2021 marks the one year anniversary of the launch of the ESA/NASA Solar Orbiter Mission. It was launched from Kennedy Space Center at 11:03 pm ET on February 9, 2020. This mission is a single spacecraft designed with
July 3, 2020

Welcome to Aphelion 2020: Farthest point from the Sun!

Happy Aphelion 2020! July is summer in the northern hemisphere and you might think this means we are closer to the Sun. This is a common misconception. Earth is actually farther from the Sun in July and on July 4th
October 28, 2018
X17 Solar Flare and Solar Storm of October 28, 2003 - See more at:

X17 Solar Flare and Solar Storm of October 28, 2003

On this day in 2003 (October 28), the Sun unleashed one of the largest and most geoeffective solar storms of the modern age (and consequently, one of the most studied).
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
April 6, 2018

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. But we can use objects that we are familiar with to provide
June 20, 2017

Happy June Solstice 2017! Oh and the Eclipse!

Happy June Solstice 2017! The beginning of summer for the northern hemisphere and winter for the southern hemisphere. Oh, and it is two months until the August 21, 2017 total solar eclipse! The June Solstice comes on June 21, 2017
March 20, 2017

Happy March Equinox 2017

The March equinox for 2017 begins on March 20th at 10:29 UT (6:29 am EDT.) The Spring or Vernal Equinox in the Northern Hemisphere is the Fall or Autumnal Equinox in the Southern Hemisphere and vice versa. But what is the equinox
February 24, 2017

‘The 2017 Ring of Fire’ – Annular Solar Eclipse

A ‘Ring of Fire’ for parts of South America and Africa An annular solar eclipse will grace parts of South America and Southern Africa starting on the morning of Sunday, February 26, 2017. The event begins at 12:10 UTC as
September 22, 2016

Happy September Equinox 2016

The September equinox for 2016 begins on September 22th at 14:21 UT (10:21 am EDT.) The September Equinox is the Fall or Autumnal Equinox in the Northern Hemisphere and the Spring or Vernal Equinox in the Southern Hemisphere. But what is the
June 20, 2016

A Rare Full Moon June Solstice for 2016!

For 2016, we get the special treat of a full moon on the June Solstice. This last happened in 1967 and will not happen again until 2062. The June solstice for 2016 begins on June 20th at 22:34 UT (6:34 pm EDT.)
March 20, 2016

Happy Spring Equinox 2016

The March equinox for 2016 begins on March 20th at 04:30 UT (12:30 am EDT.) The Spring or Vernal Equinox in the Northern Hemisphere is the Fall or Autumnal Equinox in the Southern Hemisphere and vice versa. But what is the equinox
June 21, 2015
Happy Summer Solstice Northern Hemisphere

Happy June Solstice 2015

The June solstice for 2015 begins on June 21st at 16:39 UT (12:39 pm EDT.) It is called the summer solstice for the Northern Hemisphere and the winter solstice for the Southern Hemisphere. But what is the solstice exactly? There are two solstices in
April 3, 2015
Total Lunar Eclipse of April 15, 2014 from

Shortest Total Lunar Eclipse of the Century – April 4, 2015

Don’t blink or you’ll miss the shortest lunar eclipse of the century! What is happening? During the early morning hours of April 4, the full moon will pass through Earth’s dark or inner shadow (umbra) creating a total lunar eclipse. Portions
March 19, 2015

March 20, 2015 Supermoon Solar Eclipse

On March 20, 2015 a supermoon total solar eclipse occurs in the Faroe Islands and Svalbard (Norway), and a partial solar eclipse in Europe, northern and eastern Asia and northern and western Africa. The eclipse starts at 07:41 UT and ends
October 23, 2014

AR12192: Biggest Sunspot of Two Solar Cycles!

As of October 23, 2014, AR12192 is now the Biggest sunspot in 2 solar cycles. Just yesterday it reached the rank of largest sunspot in cycle 24. The sunspot measures a whopping 2700 microhemispheres (MH or millionths of a visible
October 20, 2014

October 23, 2014 Partial Solar Eclipse

On Oct. 23, 2014 a partial solar eclipse will be visible to most of North America in the late afternoon. This is the last eclipse of 2014. Never look at the sun or an eclipse directly!  Eye safety during solar eclipses
October 19, 2014

The Big Spot Gives an X1.1 Solar Flare

Sunspot group, AR12192, released a strong burst of magnetic energy in the form of an X1.1 flare and a surge of solar plasma. The solar flare peaked in the GOES X-ray monitor at 5:01 UT, 10/19/2014. There was no significant
June 30, 2014

Solar Activity May Soon Be on the Rise

The active sun is rotating into view, that could mean there is solar fun to come. For the past 2 weeks that sun has been a bit quiet but that is only because the regions of current solar activity were
June 20, 2014
During the solstices, Earth reaches a point where its tilt is at the greatest angle to the plane of its orbit, causing one hemisphere to receive more daylight than the other. (NASA/Genna Duberstein)

The June 2014 Solstice

The June solstice for 2014 begins on June 21st at 10:51 UT (6:51 am EDT.) It is called the summer solstice for the Northern Hemisphere and the winter solstice for the Southern Hemisphere. But what is the solstice exactly? There are two solstices in a
April 14, 2014

Total Eclipse of the Moon – April 14-15, 2014

What is happening? During the nighttime hours of April 14 or 15 (depending on your time zone), the full moon will pass through Earth’s dark or inner shadow (umbra) creating a total lunar eclipse for most of North and South
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
October 30, 2013

A Whole Lot Happening on the Sun – In Many Types of Light

The sun has been really active lately. SDO gives us an amazing view of this activity in many different wavelengths of light. This also shows us the sun’s atmosphere in many temperatures ranging from ~4500 Kelvin or 7600 degrees Fahrenheit
August 19, 2013

SOHO/LASCO C3 Sees a Very Bright Kreutz-group Sungrazing Comet

“One of the brightest Sungrazers we’ve seen in a long time …”, tweeted Karl Battams (@SungrazerComets) of NRL’s Sungrazing Comets Project. Battams estimates the comet to be approximately 30-50 kilometers wide and expects it to reach speeds of at least 500
May 29, 2013

Giant Hole in the Solar Corona!

Aptly enough, we call these coronal holes. These dark patches in the sun million plus degree corona are areas where the solar atmosphere rapidly streams away from the sun. This stream of particles from the solar atmosphere is called the
May 27, 2013

Filament Eruption Sends CME Headed Towards STEREO Ahead and Mars

A filament erupted on the backside of the sun and was observed by the EUVI instrument on the STEREO Ahead spacecraft. The eruption produced a CME detected by STEREO-A COR2, STEREO-B COR2 and SOHO LASCO C3 around 19:24 UT, May
May 22, 2013

M5+ Solar Flare from Filament Eruption (Updated)

21:21 UT (5/23/2013) – Proton levels the eruption are still at the S2 NOAA alert level, down from S3. The particles are very apparent in SOHO/LASCO C2, showing up as “snow” on the images. 1:17 UT (5/23/2013) – Currently, a S2
May 17, 2013

CME may impact the Earth and Spitzer 5/19/2013

16:16 UT – NASA SWRC simulations indicate that the leading edge of the CME will reach Spitzer at 2:56 UT 5/19/2013 and Earth at 11:59 UT 5/19/2013 (+- 7 hrs). Roughly estimated expected maximum Kp index is 5-6 (minor to moderate).
May 14, 2013

AR11748 Releases Yet Another X Flare – X1.2

The active region that could, has again given us an X flare! That makes 4! 12:15 UT – The NASA GSFC Space Weather Research Center has estimated that the CME may give a glancing blow to Epoxi (~5/18/2013 06:00 UT) and
May 13, 2013

The 2nd X-flare for 2013

Larger than the First! – (Update) In less than 24 hours, the active region about to rotate into view has produced another X-class solar flare. 19:15 UT – The NASA GSFC Space Weather Research Center has estimated that the CME  may give
May 13, 2013

First X-flare of 2013

A new active region peaking around the edge of the sun released an X-class solar flare At 2:17 UT or 10:17 pm EDT, an active region that has not yet rotated into view produced an X1.7 solar flare on May
November 8, 2012

Two Non-Earthbound CMEs May Impact Mars and Several Spacecraft

Two CMEs (Coronal Mass Ejections) occurred in the early hours of November 8, 2012 (UT), the later one a more significant, O-type CME. The 2 CMEs are denoted with red arrows in this snapshot from the NASA Space Weather Research Center (SWRC)
July 12, 2012

Earth Bound CME Predicted with X1 Flare Event

Possible Moderate to Severe Geomagnetic Storm Sunspot group, AR11520, produced an X1.4 solar flare, peaking in the NOAA GOES X-ray monitor at 16:52 UT (12:52 EDT). This flash of electromagnetic radiation temporarily altered the upper atmosphere changing its ability to
May 6, 2012
AR11476 Flaring in Multiple Wavelengths

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 14, 2012

Unidentified Sun Object is Identified! A Little Black Spot on The Sun Today

On March 12, 2012, Sunsflare posted a video asking if anyone could identify a circular object seen in SDO coronal images. The video was also posted on Facebook with the same question posed. I answered the question on Facebook but
March 14, 2012

Comet SWAN Heading for the Sun!

Sungrazing comet seen for the first time with the SOHO/SWAN instrument. It is aptly named Comet SWAN. Ukrainian Amateur astronomer, citizen scientist, and SOHO Comet Hunter Vladimir Bezugly reported a bright blob on images taken by the SWAN instrument on
March 14, 2012

It Just Won’t Quit! More from AR11429!

  Sunspot group or active region AR11429 has almost rotated out of view but it still had enough energy to release an M7.9 X-ray solar flare, a fast coronal mass ejection (CME) and a solar energetic particle event (SEP). A
March 11, 2012

More Geomagnetic Storms Predicted for March 11, 2012

    CMEs are on their way to us! Estimated impact is March 11, 2012 around 2-3 PM EDT. High latitude aurora watchers keep lookout the night of March 11, 2012. On March 10, 2012, the sun produced 1 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 7, 2012

Double Blast – Exciting Space Weather from AR11429

Sunspot group, AR11429 (Active Region), is at it again. When it first began its journey across the Earthward side of the Sun it released an M-class flare, an X-class flare and several more M flares, along with several CMEs. Early
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
February 6, 2012

Happy 10th RHESSI!

Ten years ago yesterday (5 February 2002) saw the launch of the Reuven Ramaty High-Energy Solar Spectroscopic Imager, or RHESSI (pronounced reh-see). RHESSI was designed to study particle acceleration and energy transport during solar flares by observing the highest energy
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
November 3, 2011

The Spot Marks X!

      Sunspot group AR11339 (AR stands for Active Region) has just rotated onto the Earth facing disk of the Sun. Before coming completely into view the region had produced two M flares in 24 hours (an M4.3 flare
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
October 26, 2011

Happy 5th STEREO!

    A spectacular filament eruption from June 7, 2011 captured by the STEREO Ahead spacecraft with EUVI 304, Cor1 and Cor2. Happy Birthday STEREO!! October 26 ,2011 is the 5th anniversary of the launch of the STEREO mission and
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 23, 2011

A Prominence Breaks Free (SOHO Pick of the Week – May 20, 2011)

The STEREO (Ahead) spacecraft observed as a photogenic, solar prominence erupted and broke out into space over about 18-hour period (May 13, 2011). Prominences, notoriously unstable structures, are cooler clouds of gas that float above the Sun’s surface, tethered there
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
May 8, 2011

The Space Shuttle’s Importance to Solar Physics

With the approaching final launch (scheduled July 8, 2011) of the Space Shuttle Atlantis and the end to the 30 plus year Space Shuttle program, it is a good time to take a brief fond farewell look at the Shuttle
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
February 8, 2011

Seeing the Sun in a Whole New Light

NASA Spacecrafts Provide Never Before Seen 360° View of Sun On Super Bowl Sunday NASA’s STEREO spacecrafts captured something no one has ever seen before, a view of the entire sun. This first ever 360-degree picture of the sun will
February 4, 2011

The Day We See the Entire Sun!

Superbowl Sunday 2011 February 6, 2011 should be a date marked in everyone’s calendars. Not only is it Superbowl Sunday (XLV) here in the United States, but it will also be the first time in history that we will be
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 21, 2010
C2 CME Triple Play

A CME Triple Play

SOHO’s LASCO C2 and C3 coronagraphs caught the action as three, separate coronal mass ejections (CMEs) blasted out in succession from the Sun (Dec. 12, 2010). These were each distinct and unconnected events. The first CME event (directly on the
December 12, 2010

Epic Solar Filament Eruption from Dec. 6, 2010 Seen by STEREO

A very long solar filament that had been snaking around the Sun erupted (Dec. 6, 2010) with a flourish. STEREO (Behind) caught the action in dramatic detail in extreme ultraviolet light of Helium. It had been almost a million km
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 2, 2010

Happy Birthday SOHO!! 15 Years!!

The Solar and Heliospheric Observatory or SOHO is by many accounts the granddaddy of modern solar astronomy. SOHO is not the first space based solar observatory but it has truly ushered in a golden age for solar physics. The mission
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 18, 2010
SOHO Pick of the Week - 15 October 2010

A Twisting Solar Prominence (SOHO Pick of the Week)

The STEREO (Ahead) spacecraft caught this tumultuous solar prominence as it twisted and turned over about 18 hours, as seen in profile above the Sun?s surface, before disappearing (Oct. 8, 2010). The cloud of cooler gases, suspended by magnetic forces,
October 11, 2010
Increased Auroral Activity Oct. 11-12 from a Halo CME Oct. 6, 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 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
Exceptional Rocket Waves Destroy Sun Dog

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
The Sun Observed by SDO - 171 Angstrom and Magnetic Field

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
AV-021 SDO Rollout to Pad

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
September 22, 2010
STEREO image composite of the CME from 12/12/2008

3D Visualization of a Coronal Mass Ejection

Our good friends and colleagues at Trinity College Dublin have created a 3D visualization of the propagation of a coronal mass ejection (CME). Using multiscale image processing and 3D visualization the team reconstructed the trajectory of an earth-directed CME observed
September 9, 2010

Solar Active Region’s Farewell Blasts

Just as sunspot group AR11105 rotated out of the Earth’s view it produced a spectacular show. A large prominence erupted along with a C3 solar flare and a Coronal Mass Ejection (CME) blasted away from the sun. This great show
September 9, 2010

Solar Eruptions with STEREO Ahead

A View of the Active Sun with EUVI, COR1 and COR2 A very busy active region popped off about ten blasts of solar material over a two-day period (Aug. 31- Sept. 2, 2010). With this composited image and movie three