How I Discovered Halley’s Comet, by Edmond Halley
On Monday, June 10, in the Evening, the Sky being very serene and calm, I was desirous to take a view of the disk of Mars (then very near the Earth, and appearing very glorious) to see if I could distinguish in my 24 Foot Telescope, the Spots said to be seen on him. Directing my Tube for the purpose, I accidentally fell upon a small whitish Appearance near the Planet, resembling in all respects such a Nebula … The Reverend Mr. Miles Williams, Mr. Alban Thomas, and myself contemplated this Appearance for above an Hour … and we could not be deceiv’d as to its Reality; but the slowness of its Motion made us at that time conclude that it had none, and that it was rather a Nebula than a Comet.
Read more. [Image: Wikimedia Commons]
Saturn,cassini
Meteors, meteoroids and meteorites normally originate from asteroids and comets.
For example, if Earth passes through the tail of a comet, much of the debris burns up in the atmosphere, forming a meteor shower.
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November 11 each year is a day we honor those who have served in our nation’s armed forces.
Discover how we have close ties to the military, even to this day, and see who has traded in their camouflage uniform for an astronaut flight suit.
There have been veterans working for us since the beginning, even when it was still called the National Advisory Committee for Aeronautics (NACA).
Additionally, there are several active duty military members working at NASA facilities through special government programs.
Today, there are more than 1500 veterans currently employed with us. Their experiences in the military make their expertise invaluable around the agency. We value the unique leadership style they bring to the work place. Above and below are some astronaut veterans.
A Partnership for the Space Age
Since the early days of NASA, we’ve partnered with all branches of the military. We still work closely with the military today and rely on the expertise of our service members to support our missions both while in active duty and in the civilian workforce. Here are some examples of this close partnership:
The Marines helped with recovery efforts of Astronaut Alan Shepard at the end of his sub-orbital flight on May 5, 1961…a task performed across several of our missions.
Today, the Navy helps us recover spacecraft, just like the Orion space capsule…which will one day carry astronauts into deep space and eventually on our journey to Mars.
…and the Air Force has traditionally and continues to help us transport sensitive and critical space hardware around the globe.
The Coast Guard has even helped us access remote locations to collect oceanographic data as part of our efforts to study and learn more about the Earth.
We’ve partnered with the Army to use their unique capabilities at the Yuma Proving Ground to test the entry, descent and landing of our spacecraft systems.
To all the Veteran’s out there, we thank you for your service to America and your continued support of America’s space program.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
This is what a comet looks like, up close and personal.
PHOTOS FROM AN ALIEN WORLD.
I am so excited I can’t even. Source: ESA’s Flickr feed.
The Great Red Spot
To send Red Dragon spacecraft to Mars, SpaceX is building a mega-rocket called Falcon Heavy. Based on the company’s successful Falcon 9, Falcon Heavy consists of three core rocket stages, each of which is equipped with landing legs for reusability. They would use the capsule’s thrusters to make a landing.
This artist’s illustration shows how the capsule could enter Mars’ atmosphere. SpaceX has successfully returned their capsules to Earth during space station resupply missions for NASA.
The Dragon can carry seven astronauts to and from destinations like the International Space Station (not yet a manned mission to Mars I’d guess 😄). Here’s an illustration of the Dragon Version 1 (the new version has some differences), to get the idea:
credit: SpaceX, Karl Tate/Space.com
NASA Tests 3-D Printed Engine Components
3-D printing isn’t just for toys and plastic models of your head. Witness a hot fire of NASA’s newest design for rocket engine injectors, 3-D printed to up performance in a way that traditional manufacturing of the parts couldn’t attain.
The agency, which tested the experimental injectors last month at Marshall Space Flight Center in Huntsville, Ala., used a type of 3-D printing called direct laser melting. To make the parts, a machine fires a laser at metal powder under the direction of a computer design program. This deposits layers of the metal one on top of the other until the part is complete.
NASA says the technique is letting engineers build the injector out of just two parts instead of the 163 formerly needed using traditional manufacturing methods.
Keep reading
“Quantum cryptography uses the quantum properties of photons to guarantee perfect secrecy. But one of its lesser known limitations is that it only works if Alice and Bob are perfectly aligned so that they can carry out well-defined polarization measurements on the photons as they arrive. Physicists say that Alice and Bob must share the same reference frame. That’s OK if Alice and Bob are in their own ground-based labs, but it’s a problem in many other applications, such as ground-to-satellite communications or even in chip-to-chip communications, because it’s hard to keep chips still over distances of the order of the wavelength of light. Now a group of UK physicists have developed a way of doing quantum cryptography without sharing a reference frame. The trick is to use entangled triplets of photons, so-called qutrits, rather than entangled pairs. This solves the problem by embedding it in an extra abstract dimension, which is independent of space. So, as long as both Alice and Bob know the way in which all these abstract dimensions are related, the third provides a reference against which measurements of the other two can be made. That allows Alice and Bob to make any measurements they need without having to agree ahead of time on a frame of reference. That could be an important advance enabling the widespread use of quantum cryptography.”
Ted Chin
Sean Goebel - Mauna Kea Heavens 2 | gif by FD