Name: 這就是美國宇航局和SpaceX公司下一次CRS-17任務的機載設備｜發射倒計時 (This Is What the Next NASA and SpaceX CRS-17 Mission Has On Board | Countdown To Launch)
Uploaded: 2021-01-14T09:58:35.000Z
Duration: 6 min 39 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

程度副詞

SpaceX just had its first commercial launch with its Falcon Heavy and landed all three

But there’s no rest for SpaceX, it's now launching another mission, sending up numerous

science experiments including one by high school students aiming to study DNA repair

They’re also sending up tissue chips, a science fiction sounding technology which

you may remember from our conversation with expert Dr. Liz Warren, who spoke about this

SpaceX CRS17 will be utilizing it’s reusable Falcon 9 rocket, which can both deliver cargo

It’s a meticulous step-by-step process.

The booster is essentially a large autonomous robot, whose onboard internal computers successfully

The booster can either land on the ground or at sea, on the company’s droneship, Of

an interesting name for a boat, but also a nod to a famous science fiction novel, The

but it took many, many failures before SpaceX managed to successfully land its first rocket

Since then, SpaceX has made multiple successful landings.

Well, after the rocket reaches an altitude of roughly 80km,

the first and second stage separate, the latter continuing on its way to deliver the payload.

In order to reorient itself, the first stage turns on its cold engine thrusters in preparation

Following this, its 3 engines propel the booster towards the landing site, allowing for a controlled

Small, heat-resistant wings called grid fins are deployed to help guide the rocket as it

From here the engine's landing burn begins, slowing it down.

And finally, the booster's landing legs unfold for a successful touchdown.

Yes, these landings are one of the reasons that SpaceX launches are so exciting to watch.

But we can’t forget about all the innovative science payloads delivered to the ISS U.S.

What’s great about the ISS is that at its heart, it’s an international collaboration

of science where anyone can submit an experiment,

like these students from Minnesota who won the 2018 Genes in Space contest, where students

from grades 7-12 compete to have their proposed DNA experiment conducted on the ISS.

Last year’s winning team was David Li, Michelle Sung, Aarthi Vijayakumar, and Rebecca Li.

We got in touch with Aarthi to walk us through their project.

So our proposal was based off our interest in the increased risk of cancer

that astronauts face in space because of the space radiation

even when they're on the International Space Station.

So the team worked to find a way to study how cells repair their DNA in microgravity

and submitted their proposal for the contest.

So what we're doing is we have yeast cells that we will use CRISPR Cas9 to induce a break

in to simulate that space radiation and then we’ll allow the cells some time to repair

And then we amplify their DNA on the mini PCR

And based on the resulting sequence we can see if they repaired their DNA correctly or

So basically, they’ll be creating duplicates of the repaired DNA using a miniPCR.

As for analyzing the data, they’ll be using the minION sequencer which

provides real-time analysis by taking the DNA strands and using an electric current

to determine the order of the bases within each DNA strand.

The students will then take this information and determine whether the DNA sequence was

changed due to damage and if the cells were then able to repair the DNA correctly.

After becoming finalists, the team spent months working with mentors from MIT to build their

proof of concept for the final judging panel.

That meant bringing their proposal to life, by replicating the realistic timeframe that

the astronauts would have onboard the ISS as well as using readily available materials.

Until the conference, we had just not necessarily been restricted that way.

And we didn't have to think about how much of this chemical can you take on the ISS?

Can you control the heat conditions for these cells?

Things like that so that was a really good experience for us.

The results will hopefully provide more insight into whether or not astronaut DNA repairs

itself the same way in space as it does on Earth.

Their project is also making history as the first time a student-designed DNA sequencing

But until you know Until we got chosen to send it up, it became a little bit more real.

And now it's you know it's tangible, it's in the near future and we're really going

to see it launch and it feels really good.

That's something that we could come up with and work with so many cool people can

actually benefit astronauts and benefit other people in the future.

There are also four experiments being sent to the ISS U.S. National Laboratory by NCATS

& the National Institutes of Health that aim to gain a better understanding of how the

human body and organs function, with the ultimate goal of improving human health on Earth.

Tissue chips, also known as organs-on-chips, are small devices that contain human cells

grown on an artificial scaffold to model the structure and function of human tissues and

These tissue chip models provide an efficient way to study the mechanisms behind disease

One tissue chip study is investigating how microgravity and other factors affect kidney

function, since kidney problems occur more frequently in astronauts.

Another study is using tissue chips to model the lungs and bone marrow to analyze how the

immune system responds to infection in microgravity.

A third study is examining the impact of spaceflight on musculoskeletal disease biology using a

tissue chip joint model with cartilage and bone tissues.

The last tissue chip study is focused on the blood-brain barrier and aims to shed light

on the mechanisms behind neurological disorders like Alzheimer’s.

While those are the experiments focusing on human health, others like NASA JPL’s Orbiting

Carbon Observatory 3 will concentrate on tracking the distribution of carbon dioxide on Earth

by collecting measurements on specific types of atmospheric CO2.

This will give scientists more insight into carbon sources and storage sinks, which could

help in predicting the impact of growing atmospheric heat retention as well as controlling its