A Solar Tsunami

In 2006, a large solar flare from an Earth-sized sunspot produced this tsunami-like shock wave. The resulting shock wave, technically called a Moreton wave, compressed and heated up gasses including hydrogen in the photosphere of the Sun, causing it to glow more brightly. These images were taken by the Optical Solar Patrol Network (OSPAN) telescope in New Mexico. The tsunami moved at nearly a million kilometers per hour, circling Sun in a matter of minutes.

Image Credit: NSO / AURA / NSF / USAF Research Laboratory

X-rays from the Sun

Sunspots are cooler than the surrounding solar surface because the magnetic fields that create them reduce convective heating from the Sun’s interior. However, sometimes regions in the corona above sunspots can be hundreds of times hotter. The Nuclear Spectroscopic Telescope Array (NuSTAR) satellite is being used to investigate this phenomenon. This false color image shows the Sun in ultraviolet light (red ) as seen by the orbiting Solar Dynamics Observatory . X-ray imagery (green and blue) detected by NuSTAR has been superimposed, highlighting regions of extremely high temperature.

Image Credit: NASA

Staring at the Sun

On 29 April, 2015, three satellite observatories—NuSTAR, Hinode, and Solar Dynamics Observatory—all stared at our Sun. This image merges data from  Nuclear Spectroscopic Telescope Array, or NuSTAR (high-energy x-rays shown in blue), Japan’s Hinode spacecraft (low-energy x-rays in green), and SDO (extreme UV in yellow and red). The blue-white NuSTAR data pinpoint the most energetic areas.

Image Credit: NASA  /JPL-Caltech / GSFC / JAXA

A Sunquake

The Sun has quakes—earthquake-like waves tha ripple through it. This is a movie of a sunquake on 30 July, 2011. The left frame shows the active region of a solar flare as seen in visible light (amber) as well as in extreme ultraviolet (red). The right frame shows the ripples on Sun’s outlying surface for up to 42 minutes after the onset of the flare, which is marked by the label “IP” for impulsive flare on the time scale.
Video Credit: NASA

The Far Side

FarSideUVThe STEREO (Solar TErrestrial RElations Observatory) mission used a pair of spacecraft launched into orbit around the Sun. One slowly moved ahead of the Earth, and the other slowly lagged behind. Their separation allowed for simultaneous stereoscopic images to be taken of the Sun. The lagging spacecraft failed in 2014, but the leading spacecraft is still operational. This picture of the Sun was taken with the Extreme Ultraviolet Imager onboard the Solar TErrestrial RElations Observatory Ahead (STEREO-A) spacecraft. The spacecraft collects images in several wavelengths of light that are invisible to the human eye. This image shows the sun at a wavelength of 17.1 nm which which is usually coded in blue for false color imaging. STEREO-A is out of communication with the Earth when it’s on the far side of the Sun, where it operates in safe mode, collecting and saving data from its instruments. This image was taken by STEREO-A in July, 2015, from a point of view on the far side of the solar system as it had moved far enough around in its orbit to regain contact with the Earth.

Image Credit: NASA

Listening to the Sun

The Parker Solar Probe’s FIELDS instrument can eavesdrop on the electric and magnetic fluctuations caused by the charged particles and plasma waves in the solar wind emitted by the Sun. It can “hear” when the waves and particles interact with one another, recording frequency and amplitude variations, resulting in some weird sounds.

Video Credit: NASA / JHUAPL

The Warmth of the Sun

The Parker Solar Probe is alive and well after skimming by the Sun at just 25 million km from the Sun’s surface. At its perihelion on 5 November, the spacecraft reached a top speed of almost 343,000 km/h, setting a new record for spacecraft speed. On subsequent orbits the spacecraft will repeatedly break its own speed record as it draws closer to the Sun and the its speed increases at perihelion.

Mission controllers at the Johns Hopkins University Applied Physics Lab received the status beacon from the spacecraft at 21:46 UTC on the 7th indicating that the Probe is operating well with all instruments running and collecting science data and, if there were any minor issues, they were resolved autonomously by the spacecraft.

At perihelion the intense sunlight heated the Sun-facing side of the spacecraft’s Thermal Protection System to almost 450 C, hot enough to melt solder, but the spacecraft instruments and systems protected by the heat shield were generally kept in the around 25 C, a comfortable shirt-sleeve temperature. On the closet approach, the thermal shield will be exposed to a temperature around 1400 C.

It will be several weeks after the end of the solar encounter phase before the science data begins downlinking to Earth.

Video Credits: NASA / JHUAPL