OrbitalHub

NASA dixit:

“NASA’s Juno spacecraft has crossed the boundary of Jupiter’s immense magnetic field. Juno’s Waves instrument recorded the encounter with the bow shock over the course of about two hours on June 24, 2016. “Bow shock” is where the supersonic solar wind is heated and slowed by Jupiter’s magnetosphere. It is analogous to a sonic boom on Earth. The next day, June 25, 2016, the Waves instrument witnessed the crossing of the magnetopause. “Trapped continuum radiation” refers to waves trapped in a low-density cavity in Jupiter’s magnetosphere. […]

After nearly five years traveling through space to its destination, NASA’s Juno spacecraft will arrive in orbit around Jupiter on July 4, 2016. This video shows a peek of what the spacecraft saw as it closed in on its destination. Jupiter is visible along with the four Galilean moons: Callisto, Ganymede, Europa and Io. The images were taken prior to June 30, 2016, when the JunoCam camera and science instruments were turned off to prepare the spacecraft for the daring orbit insertion maneuver.”

Video credit: NASA Jet Propulsion Laboratory

NASA dixit:

“NASA GSFC solar scientist Holly Gilbert explains a computer model of the sun’s magnetic field.

Grasping what drives that magnetic system is crucial for understanding the nature of space throughout the solar system: The sun’s invisible magnetic field is responsible for everything from the solar explosions that cause space weather on Earth – such as auroras – to the interplanetary magnetic field and radiation through which our spacecraft journeying around the solar system must travel.

We can observe the shape of the magnetic fields above the sun’s surface because they guide the motion of that plasma – the loops and towers of material in the corona glow brightly in EUV images. Additionally, the footpoints on the sun’s surface, or photosphere, of these magnetic loops can be more precisely measured using an instrument called a magnetograph, which measures the strength and direction of magnetic fields.

Scientists also turn to models. They combine their observations – measurements of the magnetic field strength and direction on the solar surface – with an understanding of how solar material moves and magnetism to fill in the gaps. Simulations such as the Potential Field Source Surface, or PFSS, model – shown in the accompanying video – can help illustrate exactly how magnetic fields undulate around the sun. Models like PFSS can give us a good idea of what the solar magnetic field looks like in the sun’s corona and even on the sun’s far side.”

Video credit: NASA’s Goddard Space Flight Center

NASA dixit:

“This artist’s rendering illustrates new findings about a star shredded by a black hole. When a star wanders too close to a black hole, intense tidal forces rip the star apart. In these events, called “tidal disruptions,” some of the stellar debris is flung outward at high speed while the rest falls toward the black hole. This causes a distinct X-ray flare that can last for a few years. NASA’s Chandra X-ray Observatory, Swift Gamma-ray Burst Explorer, and ESA/NASA’s XMM-Newton collected different pieces of this astronomical puzzle in a tidal disruption event called ASASSN-14li, which was found in an optical search by the All-Sky Automated Survey for Supernovae (ASAS-SN) in November 2014. The event occurred near a super-massive black hole estimated to weigh a few million times the mass of the sun in the center of PGC 043234, a galaxy that lies about 290 million light-years away. Astronomers hope to find more events like ASASSN-14li to test theoretical models about how black holes affect their environments.

During the tidal disruption event, filaments containing much of the star’s mass fall toward the black hole. Eventually these gaseous filaments merge into a smooth, hot disk glowing brightly in X-rays. As the disk forms, its central region heats up tremendously, which drives a flow of material, called a wind, away from the disk.”

Video credit: NASA’s Goddard Space Flight Center

NASA dixit:

“The sun is always changing and NASA’s Solar Dynamics Observatory is always watching. Launched on Feb. 11, 2010, SDO keeps a 24-hour eye on the entire disk of the sun, with a prime view of the graceful dance of solar material coursing through the sun’s atmosphere, the corona. SDO’s sixth year in orbit was no exception. This video shows that entire sixth year — from Jan. 1, 2015, to Jan. 28, 2016, as one time-lapse sequence. At full quality on YouTube, this video is ultra-high definition 3840×2160 and 29.97 frames per second. Each frame represents 2 hours. […]

SDO’s Atmospheric Imaging Assembly (AIA) captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown here are based on a wavelength of 171 angstroms, which is in the extreme ultraviolet range and shows solar material at around 600,000 kelvins (about 1,079,540 degrees F). In this wavelength it is easy to see the sun’s 25-day rotation.

During the course of the video, the sun subtly increases and decreases in apparent size. This is because the distance between the SDO spacecraft and the sun varies over time. The image is, however, remarkably consistent and stable despite the fact that SDO orbits Earth at 6,876 mph, and Earth orbits the sun at 67,062 mph.

Scientists study these images to better understand the complex electromagnetic system causing the constant movement on the sun, which can ultimately have an effect closer to Earth, too. Flares and another type of solar explosion called coronal mass ejections can sometimes disrupt technology in space. Moreover, studying our closest star is one way of learning about other stars in the galaxy. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, built, operates and manages the SDO spacecraft for NASA’s Science Mission Directorate in Washington, D.C.”

Video credit: NASA’s Goddard Space Flight Center/Wiessinger

Music credit: “Tides,” a track available from Killer Tracks

NASA dixit:

“Around 13 times per century, Mercury passes between Earth and the sun in a rare astronomical event known as a planetary transit. The 2016 Mercury transit occurred on May 9, between roughly 7:12 a.m. and 2:42 p.m. EDT.”

Wikipedia dixit:

“A transit of Mercury across the Sun takes place when the planet Mercury passes directly between the Sun and a superior planet, becoming visible against (and hence obscuring a small portion of) the solar disk. During a transit, Mercury can be seen as a very small black disk moving across the face of the Sun. Transits of Mercury with respect to Earth are much more frequent than transits of Venus, with about 13 or 14 per century, in part because Mercury is closer to the Sun and orbits it more rapidly. Transits of Mercury occur in May or November. The last four transits occurred in 1999, 2003, 2006, and May 9, 2016. The next will occur on November 11, 2019, and then on November 13, 2032. A typical transit lasts several hours.

On June 3, 2014, the Mars rover Curiosity observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth.”

Video credit: NASA’s Goddard Space Flight Center/Genna Duberstein

Music credit: Encompass by Mark Petrie

NASA dixit:

“On April 17, 2016, an active region on the sun’s right side released a mid-level solar flare, captured here by NASA’s Solar Dynamics Observatory. This solar flare caused moderate radio blackouts, according to NOAA’s Space Weather Prediction Center. Scientists study active regions – which are areas of intense magnetism – to better understand why they sometimes erupt with such flares. This video was captured in several wavelengths of extreme ultraviolet light, a type of light that is typically invisible to our eyes, but is color-coded in SDO images for easy viewing.”

Video credit: NASA’s Goddard Space Flight Center/SDO/Genna Duberstein