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.
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 […]
October 28, 2018

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).
December 21, 2017

Happy December 2017 Solstice!

The December solstice for 2017 begins on Dec. 21st at 16:28 UT (11:28 am EST). It is called the winter solstice for the Northern Hemisphere and the summer solstice for the Southern Hemisphere. But what is the solstice exactly? There […]
December 20, 2016

Happy December 2016 Solstice!

The December solstice for 2016 begins on Dec. 21st at 10:44 UT (5:44 am EST). It is called the winter solstice for the Northern Hemisphere and the summer solstice for the Southern Hemisphere.   But what is the solstice exactly? […]
March 2, 2015

NASA’s Magnetospheric Multiscale (MMS) Mission: Studying magnetic fields around the Earth

By looking close to home, NASA’s newest mission with provide a window to the universe. Countdown to MMS Launch [ujicountdown id=”Countdown to MMS Launch” expire=”2015/03/12 22:44″ hide=”” url=”” subscr=””] The Magnetospheric Multiscale, or MMS, mission was created to study how magnetic […]
December 21, 2014

The December 2014 Solstice

The December solstice for 2014 begins on Dec. 21st at 23:03 UT (6:03 pm EST, 3:03 pm PST.) It is called the winter solstice for the Northern Hemisphere and the summer solstice for the Southern Hemisphere. But what is the […]
October 22, 2014

Another X-flare from AR12192

14:28 UT – Flare peaked in GOES X-rays at X1.6   14:17 UT – The flare is still in progress but at the X1.4 level. NOAA/SWPC issued a R3 (out of 5) radio blackout (Wide area blackout of HF (high […]
September 10, 2014

AR12158 Gives Away an X-flare and CME

AR12158 produced an X1.6 flare along with a coronal mass ejection. The flare peaked in X-rays at 17:45 UT. 18:20 UT (9/11/2014) – This movie is a difference movie created by Dr. Nariaki Nitta (@halocme) from the Lockheed Martin Solar and […]
September 2, 2014

A Dazzling Eruption Captured by STEREO Behind

SDO and SOHO were not the only spacecraft to capture the spectacular eruption off the East (left) limb of the sun on August 24, 2014. The M5.9 flare (at 12:17 UT) from AR 12151 was seen by the STEREO SECCHI […]
July 8, 2014

Another M-flare from AR12113

01:22 UT – AR12113 produced an M1.2 flare that peaked in GOES X-ray at 00:26 UT Type II radio emission was detected at 00:29 UT. This emission is associated with a solar eruption and typically indicate a coronal mass ejection […]
July 8, 2014

AR12113 Erupts with an M6.5 Flare

03:11 UT – Space Weather researchers at NASA/GSFC have determined the CME may affect Mars and Spitzer as well as possibly glance Earth. The CME has an estimated speed of 725 km/s. Below is a computer model showing the CMEs […]
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 10, 2014

X2.2 Solar Flare from New Region on Southeast Limb

12:05 UT – X flare!! An X2.2 solar flare from a new region (AR12087) on the southeast limb is underway. The flare peaked in x-rays around 11:42 UT. Here is a snapshot from the SDO/AIA 94 angstrom channel with the […]
June 7, 2014

CME from Filament Eruption Brushes Earth

The CME is here! As predicted the CME from the June 4 filament eruption impacted Earth’s magnetosphere around 16:30 UT with a glancing blow and created a minor geomagnetic disturbance. The plot above shows the solar wind measured by the ACE spacecraft, […]
June 6, 2014

Possible Glancing Blow CME

The slow CME produced by the giant filament eruption from June 4 could give Earth a glancing blow. The impact should be very weak but there could be a minor geomagnetic enhancement on June 7. High latitude aurora watchers may […]
January 29, 2014

A Long Lunar Transit for SDO – Jan. 30, 2014

UPDATES 16:17 UT (11:17 UT) – The transit ends with a bang! – an M6.6 flare peaked at 16:11 from AR11967. These images are from just before the flare peak at around 16:00 UT (11:00 EST) again in all 9 SDO/AIA wavelengths. […]
January 28, 2014

It’s Back – AR11944 is back as AR11967

Sunspot group or active region AR11944 that gave us such a show at the beginning of the year is back. After taking its trip around the sun it has rotated onto the Earth facing solar disk and NOAA has labeled it […]
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 […]
October 25, 2013

X Marks the New Spot! (Updated)

The newest active region on the sun has given us an X-flare and a CME! 15:10 UT (10/25/2013) X again! AR11882 kicked it up again with an X2.1 peaking at 15:03 UT. A multi-million degree snapshot with SDO/AIA 94 angstrom. […]
September 30, 2013

Spectacular Erupting Filament with Earth-directed Space Weather

A huge filament erupted from the sun producing a beautiful coronal mass ejection (CME) and solar energetic particle event. Around 21 UT, 9/29/2013 a filament erupted from the northwest quadrant of the sun. It started from the surface with a […]
August 22, 2013

Slow Earth-directed Halo CME

This time a CME is headed directly for us! Around 5:24 UT (1:24 EDT), the SOHO/LASCO C2 instrument caught a first glimpse at a CME leaving the sun directly for Earth. The CME is traveling at a fairly slow ~610 […]
August 20, 2013

Aurora Ahead? – Filament Eruption with an Earth-directed CME

There may be a geomagnetic storm in store for Earth. Lookout aurora watchers! A filament ~50 Earths in length (~400,000 miles) erupted from the Sun’s southern hemisphere in the southwest direction around 7:24 UT (4:24 am EDT). The eruption produced […]
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 13, 2013

Three’s a Charm! Another X Flare!

The unnamed region on the east limb has produced a 3rd X-class flare! (Updated) 11:44 UT – The NASA GSFC Space Weather Research Center has estimated that the CME will merge with CMEs associated with the 2 X-flares (X1.7 and X2.8) and may give a […]
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 […]
April 12, 2013

A Decent Threefer Solar Eruption – Flare, CME and Particle Storm

M6.5 solar flare, Earth-bound CME and a particle storm! AR11719 produced the largest flare of the year, an M6.5, peaking in GOES X-ray at 7:16 UT on April 11. First, we have a snapshot of the flare from the SDO/AIA […]
March 16, 2013

Waiting for a St. Patrick’s Day Aurora

Look at for Aurora tonight and tomorrow at high latitudes! Yesterday’s coronal mass ejection (CME) is expected to sweep past Earth in the last half of today (March 16, 2013) sometime around 18UT (+- 7-8 hours). Forecasts are from minor […]
February 28, 2013

Van Allen Probes Discover a 3rd Radiation Belt around Earth

Learn about this new result in a video by NASA Goddard Heliophysics Division. NASA presented these results at a press conference today. Tomorrow I will be on a Google Hangout with several of my colleagues at NASA Goddard. Ask […]
November 7, 2012

Solar Activity Picks Up, Just a Bit

    An M1.7 flare peaked at 02:23 UT, November 8, 2012. This is not really a big flare but everybody’s attention picks up when the activity level reached M-class (mine included). I don’t yet know where the event came […]
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 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 […]
April 23, 2012

A Little Flare & Some Geomagnetic Activity – April 23, 2012

At 17:40 UT, the Sun produced a C2 solar flare with a radio burst and a SCORE-C CME.  NASA Goddard Space Weather Center predicts it will reach Earth 4/27/2012 at 5:49 UT with only minor impact. Currently, there is a […]
April 22, 2012

A Prominence Eruption Sends a CME to Mercury

On April 22, 2012, filament material uncurled as an erupting prominence around sunspot group AR11463. There was a C1.8 solar flare and the resulting eruption produced a SCORE-C CME detected by SOHO/LASCO C2 at 15:30 UT.
April 17, 2012

Beautiful Eruptions from the East Limb of the Sun

An eruption of plasma from just behind the solar limb observed by SDO with the 304 Angstrom camera.This shows material at temperatures around 60,000-80,000 Kelvin. This produced a CME that went out the left side (East) of the Sun starting around 2 UT. At ~1000 km/s the CME has a SCORE O (for ordinary). NASA produced a computer model predicting the CME will impact STEREO Behind on 4/17 at 7:40 UT (but not Earth).
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 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 […]
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 […]
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 […]
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 […]
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 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

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 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 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 […]