Could we survive prolonged space travel? - Lisa Nip
-
0:08 - 0:12Prolonged space travel takes
a severe toll on the human body. -
0:12 - 0:16Microgravity impairs muscle
and bone growth, -
0:16 - 0:20and high doses of radiation
cause irreversible mutations. -
0:20 - 0:24As we seriously consider the human
species becoming space-faring, -
0:24 - 0:26a big question stands.
-
0:26 - 0:29Even if we break free
from Earth's orbit -
0:29 - 0:32and embark on long-duration
journeys among the stars, -
0:32 - 0:35can we adapt to the extreme
environments of space? -
0:35 - 0:39This won't be the first time that humans
have adapted to harsh environments -
0:39 - 0:42and evolved superhuman capabilities.
-
0:42 - 0:45Not fantastical powers like laser vision
or invisibility, -
0:45 - 0:50but physiological adaptations
for survival in tough conditions. -
0:50 - 0:53For example, on the Himalayan mountains
-
0:53 - 0:57where the highest elevation
is nine kilometers above sea level, -
0:57 - 1:01an unacclimated lowland human
will experience symptoms of hypoxia, -
1:01 - 1:04commonly known as mountain sickness.
-
1:04 - 1:08At these altitudes, the body usually
produces extra red blood cells, -
1:08 - 1:10thickening the blood
and impeding its flow. -
1:10 - 1:14But Himalayans who have lived on
these mountains for thousands of years -
1:14 - 1:18permanently evolved mechanisms
to circumvent this process -
1:18 - 1:20and maintain normal blood flow.
-
1:20 - 1:25Cases like that prove that humans
can develop permanent lifesaving traits. -
1:25 - 1:28But natural adaptation
for entire human populations -
1:28 - 1:31could take tens of thousands of years.
-
1:31 - 1:35Recent scientific advances may help us
accelerate human adaptation -
1:35 - 1:37to single generations.
-
1:37 - 1:40To thrive as a species
during space travel, -
1:40 - 1:42we could potentially develop methods
-
1:42 - 1:46to quickly program protective abilities
into ourselves. -
1:46 - 1:49A beta version of these methods
is gene therapy, -
1:49 - 1:53which we can currently use to correct
genetic diseases. -
1:53 - 1:56Gene editing technology,
which is improving rapidly, -
1:56 - 2:00allows scientists to directly change
the human genome -
2:00 - 2:04to stop undesirable processes
or make helpful substances. -
2:04 - 2:06An example of an unwanted process
-
2:06 - 2:11is what happens when our bodies
are exposed to ionizing radiation. -
2:11 - 2:15Without an atmospheric barrier
and a magnetic field like Earth's, -
2:15 - 2:20most planets and moons are bombarded
with these dangerous subatomic particles. -
2:20 - 2:22They can pass through nearly anything
-
2:22 - 2:27and would cause potentially cancerous
DNA damage to space explorers. -
2:27 - 2:30But what if we could turn the tables
on radiation? -
2:30 - 2:32Human skin produces a pigment
called melanin -
2:32 - 2:35that protects us from the filtered
radiation on Earth. -
2:35 - 2:39Melanin exists in many forms
across species, -
2:39 - 2:41and some melanin-expressing fungi
-
2:41 - 2:46use the pigment to convert radiation
into chemical energy. -
2:46 - 2:48Instead of trying to shield
the human body, -
2:48 - 2:50or rapidly repair damage,
-
2:50 - 2:52we could potentially engineer humans
-
2:52 - 2:58to adopt and express these fungal,
melanin-based energy-harvesting systems. -
2:58 - 3:03They'd then convert radiation into
useful energy while protecting our DNA. -
3:03 - 3:04This sounds pretty sci-fi,
-
3:04 - 3:08but may actually be achievable
with current technology. -
3:08 - 3:10But technology isn't the only obstacle.
-
3:10 - 3:12There are ongoing debates
on the consequences -
3:12 - 3:17and ethics of such radical alterations
to our genetic fabric. -
3:17 - 3:19Besides radiation,
-
3:19 - 3:24variation in gravitational strength
is another challenge for space travelers. -
3:24 - 3:28Until we develop artificial gravity
in a space ship or on another planet, -
3:28 - 3:32we should assume that astronauts
will spend time living in microgravity. -
3:32 - 3:35On Earth, human bone and muscle
custodial cells -
3:35 - 3:39respond to the stress
of gravity's incessant tugging -
3:39 - 3:44by renewing old cells in processes
known as remodeling and regeneration. -
3:44 - 3:46But in a microgravity environment
like Mars, -
3:46 - 3:49human bone and muscle cells
won't get these cues, -
3:49 - 3:53resulting in osteoporosis
and muscle atrophy. -
3:53 - 3:56So, how could we provide
an artificial signal for cells -
3:56 - 3:59to counteract bone and muscle loss?
-
3:59 - 4:01Again, this is speculative,
-
4:01 - 4:05but biochemically engineered microbes
inside our bodies -
4:05 - 4:09could churn out bone and muscle
remodeling signaling factors. -
4:09 - 4:11Or humans could be genetically engineered
-
4:11 - 4:15to produce more of these signals
in the absence of gravity. -
4:15 - 4:19Radiation exposure and microgravity
are only two of the many challenges -
4:19 - 4:22we will encounter in the hostile
conditions of space. -
4:22 - 4:25But if we're ethically prepared
to use them, -
4:25 - 4:29gene editing and microbial engineering
are two flexible tools -
4:29 - 4:32that could be adapted to many scenarios.
-
4:32 - 4:35In the near future, we may decide
to further develop -
4:35 - 4:39and tune these genetic tools
for the harsh realities of space living.
- Title:
- Could we survive prolonged space travel? - Lisa Nip
- Description:
-
View full lesson: http://ed.ted.com/lessons/could-we-survive-prolonged-space-travel-lisa-nip
Prolonged space travel plays a severe toll on the human body: microgravity impairs muscle and bone growth, and high doses of radiation cause irreversible mutations. As we seriously consider the human species becoming space-faring, a big question stands: even if we do break free from Earth’s orbit, can we adapt to the extreme environments of space? Lisa Nip examines our odds.
Lesson by Lisa Nip, animation by Bassam Kurdali.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TED-Ed
- Duration:
- 04:56
Jessica Ruby approved English subtitles for Could we survive prolonged space travel? - Lisa Nip | ||
Jessica Ruby accepted English subtitles for Could we survive prolonged space travel? - Lisa Nip | ||
Jessica Ruby edited English subtitles for Could we survive prolonged space travel? - Lisa Nip | ||
Jennifer Cody edited English subtitles for Could we survive prolonged space travel? - Lisa Nip |