NASA counts down to launch of first spacecraft to ‘touch Sun’

This handout illustration obtained July 6, 2018 courtesy of NASA shows an artist’s conception of NASA’s Parker Solar Probe, the spacecraft that will fly through the Sun’s corona to trace how energy and heat move through the star’s atmosphere. (AFP)
Updated 13 August 2018
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NASA counts down to launch of first spacecraft to ‘touch Sun’

TAAMPA: NASA counted down Friday to the launch of a $1.5 billion spacecraft that aims to plunge into the Sun’s sizzling atmosphere and become humanity’s first mission to explore a star.
The car-sized Parker Solar Probe is scheduled to blast off on a Delta IV Heavy rocket from Cape Canaveral, Florida early Saturday.
The 65-minute launch window opens at 3:33 am (0733 GMT), and the weather forecast is 70 percent favorable for takeoff, NASA said.
The probe’s main goal is to unveil the secrets of the corona, the unusual atmosphere around Sun.
Not only is the corona about 300 times hotter than the Sun’s surface, it also hurls powerful plasma and energetic particles that can unleash geomagnetic space storms and disrupt Earth’s power grid.
“The Parker Solar Probe will help us do a much better job of predicting when a disturbance in the solar wind could hit Earth,” said Justin Kasper, one of the project scientists and a professor at the University of Michigan.


The probe is protected by an ultra-powerful heat shield that is just 4.5 inches thick (11.43 centimeters).
The shield should enable the spacecraft to survive its close shave with the center of our solar system, coming within 3.83 million miles (6.16 million kilometers) of the Sun’s surface.
The heat shield is built to withstand radiation equivalent up to about 500 times the Sun’s radiation here on Earth.
Even in a region where temperatures can reach more than a million degrees Fahrenheit, the sunlight is expected to heat the shield to just around 2,500 degrees Fahrenheit (1,371 degrees Celsius).
Scorching, yes? But if all works as planned, the inside of the spacecraft should stay a cooler 85 F (29 C).
The goal for the Parker Solar Probe is to make 24 passes through the corona during its seven-year mission.
“The sun is full of mysteries,” said Nicky Fox, project scientist at the Johns Hopkins University Applied Physics Lab.
“We are ready. We have the perfect payload. We know the questions we want to answer.”


The tools on board will measure the expanding corona and continually flowing atmosphere known as the solar wind, which solar physicist Eugene Parker first described back in 1958.
Parker, now 91, recalled that at first, some people did not believe in his theory.
But then, the launch of NASA’s Mariner 2 spacecraft in 1962 — becoming the first robotic spacecraft to make a successful planetary encounter — proved them wrong.
“It was just a matter of sitting out the deniers for four years until the Venus Mariner 2 spacecraft showed that, by golly, there was a solar wind,” Parker said earlier this week.
He added that he is “impressed” by the Parker Solar Probe, calling it “a very complex machine.”
Scientists have wanted to build a spacecraft like this for more than 60 years, but only in recent years did the heat shield technology advance enough to be capable of protecting sensitive instruments, according to Fox.
Tools on board will measure high energy particles associated with flares and coronal mass ejections, as well as the changing magnetic field around the Sun.
“We will also be listening for plasma waves that we know flow around when particles move,” Fox added.
“And last but not least, we have a white light imager that is taking images of the atmosphere right in front of the Sun.”
When it nears the Sun, the probe will travel rapidly enough to go from New York to Tokyo in one minute — some 430,000 miles (700,000 kilometers) per hour, making it the fastest human-made object.


What We Are Reading Today: Jefferson’s Legal Commonplace Book by Thomas Jefferson

Updated 24 April 2019
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What We Are Reading Today: Jefferson’s Legal Commonplace Book by Thomas Jefferson

  • This authoritative volume is the first to contain the complete text of Jefferson’s notebook

As a law student and young lawyer in the 1760s, Thomas Jefferson began writing abstracts of English common law reports. Even after abandoning his law practice, he continued to rely on his legal commonplace book to document the legal, historical, and philosophical reading that helped shape his new role as a statesman. Indeed, he made entries in the notebook in preparation for his mission to France, as president of the US, and near the end of his life. 

This authoritative volume is the first to contain the complete text of Jefferson’s notebook, says a review on the Princeton University Press review. With more than 900 entries on such thinkers as Beccaria, Montesquieu, and Lord Kames, Jefferson’s Legal Commonplace Book is a fascinating chronicle of the evolution of Jefferson’s searching mind.

Unlike the only previous edition of Jefferson’s notebook, published in 1926, this edition features a verified text of Jefferson’s entries and full annotation, including essential information on the authors and books he documents. 

In addition, the volume includes a substantial introduction that places Jefferson’s text in a legal, historical and biographical context.