“NASA’s Transiting Exoplanet Survey Satellite – TESS – will fly in an orbit that completes two circuits around Earth every time the Moon orbits once. This special orbit will allow TESS’s cameras to monitor each patch of sky continuously for nearly a month at a time. To get into this orbit, TESS will make a series of loops culminating in a lunar gravity assist, which will give it the final push it needs. TESS will reach its orbit about 60 days after launch.”
Music Credit: “Drive to Succeed” from Killer Tracks
“Mars has two moons, Phobos and Deimos. Both are small, airless bodies with irregular shapes. Because they lack protective atmospheres and magnetospheres, Phobos and Deimos are directly exposed to the solar wind for part of their orbits. Now, a study from NASA’s Goddard Space Flight Center suggests that the solar wind creates a complex electrical environment around Phobos, giving its night side and shadowed craters a static electric charge. This could impact plans for future robotic and human explorers to study the moons of Mars.”
“Scheduled to launch in the mid-2020s, the Wide Field Infrared Survey Telescope (WFIRST) will function as Hubble’s wide-eyed cousin. While just as sensitive as Hubble’s cameras, WFIRST’s 300-megapixel Wide Field Instrument will image a sky area 100 times larger. This means a single WFIRST image will hold the equivalent detail of 100 pictures from Hubble.
The mission’s wide field of view will allow it to generate a never-before-seen big picture of the universe, which will help astronomers explore some of the greatest mysteries of the cosmos, like why the expansion of the universe seems to be accelerating. Some scientists attribute the speed-up to dark energy, an unexplained pressure that makes up 68 percent of the total content of the cosmos.
The Wide Field Instrument will also allow WFIRST to measure the matter in hundreds of millions of distant galaxies through a phenomenon dictated by Einstein’s relativity theory. Massive objects like galaxies curve space-time in a way that bends light passing near them, creating a distorted, magnified view of far-off galaxies behind them. WFIRST will paint a broad picture of how matter is structured throughout the universe, allowing scientists to put the governing physics of its assembly to the ultimate test.
WFIRST can use this same light-bending phenomenon to study planets beyond our solar system, known as exoplanets. In a process called microlensing, a foreground star in our galaxy acts as the lens. When its motion randomly aligns with a distant background star, the lens magnifies, brightens and distorts the background star. WFIRST’s microlensing survey will monitor 100 million stars for hundreds of days and is expected to find about 2,500 planets, well targeted at rocky planets in and beyond the region where liquid water may exist.
These results will make WFIRST an ideal companion to missions like NASA’s Kepler and the upcoming Transiting Exoplanet Survey Satellite (TESS), which are designed to study larger planets orbiting closer to their host stars. Together, discoveries from these three missions will help complete the census of planets beyond our solar system. The combined data will also overlap in a critical area known as the habitable zone, the orbiting distance from a host star that would permit a planet’s surface to harbor liquid water — and potentially life.
By pioneering an array of innovative technologies, WFIRST will serve as a multipurpose mission, formulating a big picture of the universe and helping us answer some of the most profound questions in astrophysics, such as how the universe evolved into what we see today, its ultimate fate and whether we are alone. “
“For hundreds of years, this gaseous giant planet appeared shrouded in colorful bands of clouds extending from dusk to dawn, referred to as zones and belts. The bands were thought to be an expression of Jovian weather, related to winds blowing eastward and westward at different speeds.
This animation illustrates a recent discovery by Juno that demonstrates these east-west flows, also known as jet-streams penetrate deep into the planet’s atmosphere, to a depth of about 1,900 miles (3,000 kilometers). Due to Jupiter’s rapid rotation (Jupiter’s day is about 10 hours), these flows extend into the interior parallel to Jupiter’s axis of rotation, in the form of nested cylinders. Below this layer the flows decay, possibly slowed by Jupiter’s strong magnetic field.
The depth of these flows surprised scientists who estimate the total mass involved in these jet streams to be about 1% of Jupiter’s mass (Jupiter’s mass is over 300 times that of Earth). This discovery was revealed by the unprecedented accuracy of Juno’s measurements of the gravity field.”
“These observations of Phobos and Saturn were taken by the Super Resolution Channel of the High Resolution Stereo Camera on Mars Express. The video comprises 30 separate images acquired during Mars Express orbit 16 346 on 26 November 2016. The slight up and down movement of Saturn and Phobos in these images is caused by the oscillation of the spacecraft’s orientation after completing the turn towards the moon. Phobos can be seen in the foreground, partially illuminated, with Saturn visible as a small ringed dot in the distance.”
“ESA’s XMM-Newton has spotted surprising changes in the powerful streams of gas from two massive stars, suggesting that colliding stellar winds don’t behave as expected. Massive stars – several times larger than our Sun – lead turbulent lives, burning their nuclear fuel rapidly and pouring large amounts of material into their surroundings throughout their short but sparkling lives.
These fierce stellar winds can carry the equivalent of Earth’s mass in a month and travel at millions of kilometres per hour, so when two such winds collide they unleash enormous amounts of energy. The cosmic clash heats the gas to millions of degrees, making it shine brightly in X-rays.
Normally, colliding winds change little because neither do the stars nor their orbits. However, some massive stars behave dramatically. This is the case with HD 5980, a pairing of two huge stars each 60 times the mass of our Sun and only about 100 million kilometres apart – closer than we are to our star. One had a major outburst in 1994, reminiscent of the eruption that turned Eta Carinae into the second brightest star in the sky for about 18 years in the 19th century. While it is now too late to study Eta Carinae’s historic eruption, astronomers have been observing HD 5980 with X-ray telescopes to study the hot gas.”
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