James Webb Space Telescope

 

NASA’s much-awaited James Webb Space Telescope may finally get its place in the night sky: NASA says it’s now completed its final litany of critical software and electrical systems tests, theoretically clearing it for launch as soon as 2021.

It’s the “largest and most technically complex space science telescope NASA has ever built,” according to a statement. It’s an international collaboration of unprecedented proportions between NASA, the European Space Agency, and the Canadian Space Agency.

Engineers worked 24 hours a day for 15 days straight, executing over a thousand scripts and instructions — a 1,370 step process, according to NASA.

Development of the delay-plagued orbital spyglass began in 1996, with an initial launch planned in 2007. Now, after a slew of major redesigns, countless delays, and budget overruns, NASA is tentatively eyeing a March 2021 launch. The space agency will reevaluate launch readiness this month.

The 21-feet-wide telescope will observe distant space, orbiting the Sun instead of the Earth, but at a distance called the Lagrange point that will keep pace with the Earth, as illustrated in the animation below.

An origami-like sunshield the size of a tennis court will keep it cool.

Its iconic 18 hexagonal mirror segments, each over four feet in diameter, will combine post-launch into a giant reflector with an area of 25.4 square meters (273 square feet). The huge reflector will allow the telescope to observe the stars in much lower frequency ranges compared to its predecessor, NASA’s Hubble space telescope. Each mirror is fabricated from lightweight yet resilient beryllium.

The telescope will collect invaluable data using four scientific instruments, including cameras and spectrometers, to find out more about the earliest galaxies that first formed shortly after the Big Bang. It will also observe the early life cycles of stars as they form and evolve.

Another goal will be to take the temperature and investigate the chemical properties of other planetary systems to investigate if life can survive in those systems, according to NASA.

READ MORE: NASA’s James Webb Space Telescope Completes Comprehensive Systems Test [NASA]
More on the space telescope:NASA Finally Assembled The James Webb Space Telescope

Extremely Earth-Like Exoplanet

 

It’s the most similar to Earth in size and estimated temperature out of the thousands of exoplanets discovered by Kepler.

“This intriguing, distant world gives us even greater hope that a second Earth lies among the stars, waiting to be found,”  Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate in Washington, who was not part of the research, said in a statement.

The exoplanet, called Kepler -1649c, orbits its small red dwarf star within the system’s habitable zone, a distance at which rocky planets receive enough star radiation to allow for liquid water to exist. It’s almost precisely the same size as large as Earth and receives 75 percent of the amount of light Earth receives from the Sun.

In other words, it’s a distant world that’s likelier than many others to support life. At 300 light-years from Earth, it’s the most similar to Earth in size and estimated temperature out of the thousands of exoplanets discovered by the Kepler space telescope, according to the researchers.

But plenty of questions remain before we can definitively say that the planet is capable of supporting life. For one, we don’t know what its atmosphere looks like — the key determinant of the planet’s surface temperature.

The team made the discovery while re-analzying older observations from NASA’s now-retired Kepler space telescope program. Kepler -1649c orbits its star at an extremely short distance — a full revolution takes only 19.5 Earth days — alongside a similarly sized rocky planet that orbits at half the distance of Kepler-1649c.

“Out of all the mislabeled planets we’ve recovered, this one’s particularly exciting — not just because it’s in the habitable zone and Earth-size, but because of how it might interact with this neighboring planet,” Andrew Vanderburg, researcher at the University of Texas at Austin and lead author of the paper published today in The Astrophysical Journal Letters, said in the statement.

The two rocky planets orbit their host star at an exact ratio: Kepler-1649c completes nine orbits in almost exactly the same time the inner planet completes four orbits. The researchers believe this could make the system extremely stable over a long period of time.

“The more data we get, the more signs we see pointing to the notion that potentially habitable and Earth-size exoplanets are common around these kinds of stars,” said Vanderburg.

“With red dwarfs almost everywhere around our galaxy, and these small, potentially habitable and rocky planets around them, the chance one of them isn’t too different than our Earth looks a bit brighter,” he added.

READ MORE: New Earth-sized planet found in habitable sweet-spot orbit around a distant star [TechCrunch]
More on exoplanets: Bizarre Exoplanet Might Be a Gas Giant That Lost its Gas

Planetary magnetism 


The Earth’s magnetic field still remains a mystery to us in various ways. By studying the other planetary objects, we have added more questions than answers. For instance, we have evidence that our Moon’s magnetic field ceased to exist about 3 billion years ago. Is it then possible for the Earth to lose its magnetic field as well, and if so, then how?

Source: Nasa.gov / Image: Roen Kelly