Rebecca and Kimberly Yeung
Budding scientists and space explorers Rebecca and Kimberly Yeung of Seattle.

The Seattle sisters who captivated GeekWire’s audience and earned an invitation to the White House after launching a homemade craft to the edge of space are embarking on another mission this weekend.

Rebecca and Kimberly Yeung are planning to send up the Loki Lego Launcher 2.0 balloon on Saturday with the hopes of achieving a new set of goals and collecting interesting scientific data along the way.

Lego Rey
Lego Rey, from “The Force Awakens.”

In an interview with GeekWire on Thursday, the elementary school girls — who blog regularly about their exploits — revealed what might be their best-kept secret so far. They said that the R2-D2 Lego Minifigure that flew on the first mission will be replaced this time by a Lego Rey, the popular character from “Star Wars: The Force Awakens.”

Rebecca, 11, and Kimberly, 9, said they chose Rey, who was portrayed in the movie by British actress Daisy Ridley, because she is a good hero for girls. A picture of Loki, the girls’ cat, will be making a return voyage.

Since the success of the first Loki Lego Launcher last September, Rebecca and Kimberly have been busy being mini celebrity scientists.

"Our youngest innovators can change the world." —President Obama to the students at his final #WHScienceFair ??

A post shared by The Obama White House (@obamawhitehouse) on

“We’ve learned so much, with all of the great opportunities this has opened up for us,” Rebecca said. “Things like meeting the president to modeling STEM-based clothing — it’s been a really amazing experience.” And their original mission also taught them some important lessons, including this gem of advice that resonated with the science and space community last fall after GeekWire reported on the first mission.

“Well, one of the lessons that we learned was to always be optimistic because there are a lot of things that we thought were going wrong, when, in fact, everything was going right,” said Kimberly.

The experience, born out of a love for science, continues with the planning and preparation that’s been going into Loki Lego 2.0. The goals for this mission are spelled out on the girls’ blog:

  • Reach a height of 27,500 meters (90,200 feet).
  • Complete the launch and descent in less than four hours.
  • See the curvature of the earth on our video footage.
  • Compare data with our first launch and see if we observe the same.

That height is 12,000 feet higher than Loki Lego 1 rose, and the girls said they did not see the curvature of the earth on that first mission.

“Since we want to complete the launch in less than four hours, we got a bigger balloon,” said Rebecca, who will be a sixth grader this fall at Seattle’s Lakeside School. “We’re going to put more helium in it — around 75 cubic feet of helium — and that will, according to our calculations, get us up there high enough so that we can see the curvature of the earth, and faster than four hours.”

She added that the view the first time “looked pretty flat.”

Loki Lego Launcher
Testing, testing, testing. Rebecca and Kimberly Yeung prep for launch No. 2. Via Loki Lego Launcher

With a launch in their back pocket along with several months of meeting like-minded and inspiring science and space enthusiasts, the sisters have learned a few things before giving it another go. They’re applying those lessons, naturally.

“We do know that this time we’re going to make sure to weigh everything that we have,” said Kimberly, a soon-to-be fourth grader at Seattle Country Day School. “Because last time our calculations weren’t correct. It was slower than expected, and because of it’s speed it was carrying farther than we expected because we didn’t measure the rope and tape that we used to connect things.”

As for the science on board, they’re attaching a solar panel and voltage/current sensor, which has gone through rigorous pre-flight testing.

“Our sensor is measuring both voltage, current and power and we’re going to use the solar panel and connect it to it to measure how much solar energy our solar panel absorbs,” Rebecca said. “Our current hypothesis is that as we get farther up, there will be less particles to block the sun’s rays and we’ll get more solar energy. So we’re trying to test our hypothesis.”

“If we get that to work, that would definitely probably be the best,” Kimberly added.

GeekWire Awards
Rebecca and Kimberly Yeung are interviewed on the orange carpet by GeekWire’s Todd Bishop, left, and Taylor Soper at the GeekWire Awards in May. (Via Loki Lego Launcher)

The Yeungs have also added a redundant tracking system in the form of an APRS Radio Bug which relies on radio waves to communicate data to a web page. The first tracking system, which used GPS and wouldn’t transmit data when it got too high, will remain on board. A single GoPro camera will also be used instead of two, to reduce weight.

When not planning to launch a balloon, again, to the edge of space, summer sounds pretty typical for the girls.

“I’m doing a lot of different types of camps,” Kimberly said. “I’ve done sports camps and just last week I did a camp called Jump into the Future at University of Washington. That was really fun.”

In anticipation of Loki Lego Launcher 2.0 taking flight from central Washington sometime on Saturday, have another look at the video, shot by dad Winston Yeung, of the first mission. And make sure to listen to the GeekWire podcast from last September when the girls shared their love of science, space and the power of optimism.

And check back with GeekWire for an update on how Rebecca and Kimberly — and Loki and Rey — fared the second time around.

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