Black Holes and Snocones

FIRST DAY: Today the kids checked in to their Shoreline school first time for the 2013/14 school year. We'll be up there one day a week for science and math classes.

Today, there was none of that, though. They had their photos taken, got free hot dogs and snocones. CJ was adventurous and chose a "Graveyard" flavor, which was a mystery mix from the older students running the stand.

Annabelle opted for the "Tiger's Blood," which was a mix of the red flavors.

At 1 p.m., we reported to the library where CJ was issued his 'new'/loaner Mac book, about which he is Very Excited. He/we started to get to know it today.  CJ doesn't seem to have any trouble navigating the Mac environment so far.

WORKIN' THROUGH IT: We're making good progress on Week 1 of "From the Big Bang to Dark Energy." Today, there was talk of Einstein's space warps, which was compelling, of course. We also were introduced to the formula for escape velocity, which is the speed needed to be free from the gravitational attraction of a massive body, without further propulsion. 

                                                            

I asked the kids who might work with escape velocities on the job. They both pretty quickly came up with rocket scientists. Per Wikipedia, "On the surface of the Earth, the escape velocity is about 11.2 kilometers per second(~6.96 mi/s), which is approximately 34 times the speed of sound (Mach 34)."

                                        

Launched in 1959, Luna 1 was the very first object to reach escape velocity from Earth!

We also learned how to calculate the radius of a black hole, using the Schwarzschild radius.  It's 

where  is the Schwarzschild radius;  is the gravitational constant;  is the mass of the object;  is the speed of light in vacuum.

I know this will come in handy countless times in the future. :)

FOR A SPIN:  We've been watching and reading about preparations for the launch on Sept. 6 of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) observatory.  Recently, it went through final preparations, which included checking alignment, checking the propulsion system for leaks, inspecting and repairing solar panels, and final electrical tests. After those things checked out, it was time for spin testing and fueling.

                           

Per a NASA press release, "To make sure that the spacecraft is perfectly balanced for flight, engineers mounted it onto a spin table and rotate it at high speeds, approximately one revolution per second. The team measured any offsets during the spinning, and then added small weights to the spacecraft to balance it. Once the spacecraft was balanced dry, the team loaded the propulsion tanks with fuel, oxidizer, and pressurant. The spin testing was performed again "wet," or with fuel, in order to see if the balance changed with the full fuel tanks."  The photo above is of the dry spin test. Look at that thing go!

LADEE has now been encapsulated into the nose-cone of the Minotaur V rocket at NASA's Wallops Flight Facility in Virginia/

                  

                         PHOTO CREDIT: NASA EDGE/Franklin Fitzgerald

It's set to launch Friday evening at 11:27 EDT. We're selfishly hoping the launch is delayed a couple of days, so we could potentially see it from NYC. 

In case you're wondering just what LADEE will be looking for on the moon, check out this NASA overview.