Sunday, September 18, 2016

50 Years Ago: Gemini 11

Beautiful blast-off of Gemini 11 on the Titan II rocket.
Just fifty years ago, astronauts Pete Conrad and Richard (Dick) Gordon lifted off from the LC-19 pad at Cape Kennedy, Florida.  The flight took place just an hour and a half after the blast-off of an Atlas-Agena mission from LC-14.

Atlas rocket carrying an Agena docking spacecraft lifts off from pad LC-14.
Busy times at the Cape. While Gemini 11 lifts off LC-19, in the distance you can see SA-500F, a dummy Saturn V rocket used to test the launch facilities of Pad LC-39A before actual missions begin.

A close-up view of the Gemini 11 Launch.
In a Gemini first, the manned capsule caught up to the Agena target vehicle 94 minutes after launch and docked without problems. The rapid flight to the docking vehicle was termed "direct ascent" rendezvous and docking, and is similar to the short 6-hour Soyuz flights used today for astronauts to reach the ISS in a minimal time. Once docked, the astronauts used the motor aboard the Agena to propel them into a higher record altitude of 850 miles, more than four times higher than the ISS orbits these days.
NASA publicity shot of Richard Gordon (L), and Pete Conrad (R).
The astronauts did not stay in the higher orbit. They docked and undocked a total of four times during the mission, and lowered their main orbital height to about 184 miles up. They then prepared for the main experiment of the mission, to simulate some artificial gravity using a spinning of the combined spaceships.
At a press conference, Pete Conrad uses models of the Gemini and Agena spacecraft to demonstrate how the tether between the vehicle would be used to keep the craft together while spinning around an axis point.
In the first mission EVA, Richard Gordon exited the Gemini capsule to attach a tether between the two vehicles. During the two hour plan for the spacewalk, he needed to move over to the Agena's docking collar and remove the 100-meter tether, then attach it to the prepared points on the Agena dock and the Gemini nose. Unfortunately, the activities of the EVA turned out to be much more fatiguing and problematic than the training had suggest it would be. The EVA had to be shortened, but Gordon successfully connected the tether.
Picture of Gordon preparing to exit the Gemini spacecraft.
Image of Gordon moving between the two spacecraft. Most of the footage of Gordon outside the craft, taken by Conrad, was of poor quality because of poor visibility in his window. 
The slack in the tether is very apparent in this image taken by Gordon.
The tether experiment did not go as planned. They were never able to get the taught tether stability needed to fully generate a proper rotation, but the spinning they were able to achieve gave them a measurable amount of centrifugal force.  Later, in a second EVA, Gordon was able to perform a non-tiring series of experiments and photography sessions.
High-quality image of Australia from Gemini 11.
Moonrise over the curvature of the Earth.
Three days after launch, the mission ended in a great example of the advances America was making with computer technology. In the first fully-computerized automatic re-entry, the Gemini 11 spacecraft precisely landed only 2.8 miles from its planned position, close by the recovery ship USS Guam.
USS Guam alongside the spacecraft and recovery frogmen.
Gordon and Conrad on the deck of USS Guam.
An interesting photo I found comparing the size difference between the two-man Gemini spacecraft and the original one-astronaut Mercury space capsule. Keep in mind that the white-colored service module section behind the Gemini astronauts did not return to Earth with the capsule but were destroyed after separation and re-entry.



Monday, September 12, 2016

Expedition 48 Returns to Earth

It's good to be home. The space voyagers rest and remember how gravity affects their bodies after being helped from their Soyuz return capsule.

After a six-month stay aboard the International Space Station, Expedition 48 has safely returned to Earth to being debriefings and analysis of their medical situation and the performance of their tasks. The Russian spacecraft was TMA-20M, which had left the Earth last March on the 129th Soyuz flight. The craft was under the command of Alexey Ovchinin and crewed by Expedition 48 commander Jeff Williams and flight engineer Oleg Skripochka. 
Ground views of the fiery re-entry of the Soyuz capsule and the burn-up of the non-protective modules.
Besides working on hundreds of science experiments during their stay, the Expedition 48 crew highlights include the installation of the inflatable Bigelow module for testing, the installation of a new International space dock mechanism, receiving robotic supply spacecraft, and two EVAs for servicing the station and installing the spacedock.
Back in the atmosphere. Soyuz hangs beneath a fully open parachute.
Touchdown took place in the steppes of Kazakhstan. With the departure of the Expedition 48 crew, Expedition 49 now begins on the ISS with the three remaining crew: Commander Anatoly Ivanishin (RosCosmos), Takuya Onishi (Japan Space Agency), and Kate Rubin (NASA). They will be reinforced later this month when another Soyuz lifts off from Baikonur, carrying Shane Kimbrough, Sergey Ryzhikov, and Andrey Borisenko. The launch is scheduled for September 23rd.

Monday, September 5, 2016

Falcon Explodes on Pad; Satellite Destroyed

Explosion begins just below the payload section on the Falcon 9 rocket. Credit: SpaceX

SpaceX suffered a dramatic setback Thursday September 1st when its Falcon 9 rocket exploded on pad SLC-40 at Cape Canaveral. The payload, a communications satellite for Israel designated AMOS-6, was vaporized in the blast.  The explosion occurred during a firing test, when an unexplained detonation occurred in the 2nd stage liquid-oxygen (LOX) tank. SpaceX engineers worked diligently to put out the fires and secure the facility. According to reports in, SpaceX claims the explosion happened while fuel was loading into the LOX 2nd stage tank, at about 7:07 am Mountain Time. This is the second lost mission for SpaceX in 2 years, and there are many questions being raised about what went wrong while investigators do their best to find out why this tragedy happened.

The AMOS-6 payload section before the LOX fuel loading. Credit: SpaceX.
AMOS-6 was a communications satellite built by the Israeli firm Israel Aerospace Industries. It was supposed to take the place of the worn-out AMOS-2 satellite, at an orbital height of 22,000 miles.

Expedition 48 Ending on a High Note

ISS Commander Jeff Williams installing new High-Definition Camera. Credit: NASA.

Ending on a high note, indeed. Beyond the atmosphere high. On Thursday September 1st, Expedition 48 commander Jeff Williams, assisted by flight engineer Kate Rubins, exited the Quest airlock and began a 6-hour, 48-minute EVA outside the ISS. Their mission was to install the first new high-definition camera on the Truss, and tighten bolts on a solar array joint. The EVA makes 5 spacewalks for Williams and the second for Rubins. In fact, they had just performed another EVA just 13 days earlier.

Difference between old camera and new.

Before the camera installation, the two astronauts worked on retracting the  TTCR radiation cooling array. Once it was collapsed and secured, a cover was put over the panels so it can be stored for a while, acting as backup in case it is needed. Then the camera was retrieved from the airlock, and they installed it on the P1 Truss at camera Point 9. While Williams finished the camera installation, Rubins moved over to one of the giant solar panel joints to tighten several of the bolts. Cameras had noticed vibration before this on some of the panel movements.

With the end of the EVA, the astronauts now begin preparing for the return of Expedition 48 to Earth on September 6, and the beginning of Expedition 49.