Space Science and the Search for ET and Extraterrestrial Life

30 January 2005
Presented by Chris Smith, Helen Scales.

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In this show we go in search of the origins of life, including extraterrestrial life, and the ingredients that make a planet a good home with astronomer Dr. Simon Goodwin, from the University of Cardiff, and Dr. Monica Grady, from the Natural History Museum, London. Also joining us on the programme are theoretical physicist Professor Michio Kaku, from City University New York, to discuss the possible existence of parallel universes, and NASA plant scientist Dr. Volker Kern, who describes interesting results when moss grows in the absence of gravity aboard a spaceship...

In this episode

World's First Panda Blood Bank Built in China

A novel approach could soon be adopted by scientists in the race to save endangered pandas - the iconic trademark of the conservation movement. Scientists have almost completed the world's first panda blood bank which is being built at the Woolong Nature Reserve in Southwest China's Sichuan Province. The aim of the bloodbank is to assist researchers in studying the endangered animals' blood types, improving the chances of performing successful blood transfusions in the future. At the moment vets can only offer limited supportive measures for sick pandas and there are circumstances under which blood transfusions could help significantly to accelerate the recovery process. However, a crucial step before this can be done is to gain a better understanding of pandas' blood types, and whether, like humans, pandas have different blood 'groups'. The centre will carry out a general survey of the blood types of all 81 pandas kept there, and collect and store blood from them to help with the treatment of other animals in the future. The information collected at te blood bank will also assist the panda breeding programmes by helping to minimise the risks of inbreeding.

Naked female and male human body, from the back (posterior)

- Why Women Outlive Men

On average women outlive men by 5 years, but why?

Why Women Outlive Men

On average women outlive men by 5 years, but why?

A study from a team of scientists lead by Professor David Goldspink from Liverpool University studied 250 men and women of various ages and found that, between the ages of 17 and 70, the male heart loses around a third of contractile cells that enable the heart to beat.

This change is not seen in the female heart, suggesting that this is one reason why women live longer than men.

But it's not all bad news for the boys, because taking regular exercise can help to ward off some of the age-related changes...

When Cross-dressing Has its Advantages

Researchers studying the giant Australian cuttlefish have found that males of the species often successfully resort to the marine equivalent of cross-dressing to father offspring. During the mating season, fertile females are usually jealously guarded by large males, preventing smaller males from getting a look in. So the smaller animals often disguise themselves as females, by changing colour and arranging their tentacles in a more feminine fashion, in order to slip past the male consorts lurking nearby. Whilst this strategy is often very successful at winning them an, albeit brief, audience with the female, no one knew whether they actually succeeded in fathering any young this way. So Roger Hanlon and his colleagues have genetically fingerprinted a number cross dressing males whom they saw initiating successful matings, together with the resulting offspring. They found two out of three of the matings resulted in successful fertilisation showing, that when it comes to sex, deception sometimes pays off !

Naked female and male human body, from the back (posterior)

- Why Women Outlive Men

On average women outlive men by 5 years, but why?

Why Women Outlive Men

On average women outlive men by 5 years, but why?

A study from a team of scientists lead by Professor David Goldspink from Liverpool University studied 250 men and women of various ages and found that, between the ages of 17 and 70, the male heart loses around a third of contractile cells that enable the heart to beat.

This change is not seen in the female heart, suggesting that this is one reason why women live longer than men.

But it's not all bad news for the boys, because taking regular exercise can help to ward off some of the age-related changes...

Toxic Boat Paint Might Be Making Whales Go Deaf

A toxic chemical used to prevent barnacles from clinging to the bottoms of boats may be causing whales to go deaf and to beach themselves, according to a study by scientists at Yale University. TBT, or tributyl tin, is banned in many countries because it was found to cause genetic mutations in some acquatic animals including sea snails, but it is still widely used elsewhere. Now there is growing evidence that TBT could be causing even greater problems in the oceans by damaging animals' ears. Working on guinea pigs, researchers ahve found that TBT stops the outer hair cells in the ear from working properly, leading to hearing loss, suggesting that the same could happen to marine mammals including dolphins and whales. This would have disastrous consequences for these animals because they rely so heavily on their sonar or echolocation for navigation and hunting.

Parallel Universes

Chris - You work on the concept of parallel universes...

Michio - People have often wondered whether there is a carbon copy of us elsewhere that's leading a different life. This idea was often laughed at, but this doesn't happen at physics conferences anymore! Advancing space technology has provided us with baby pictures of the universe. The data from these are consistent with a rapidly expanding universe, but there is nothing in those photos to say that the big bang couldn't happen again. Our universe is like a bubble and we are trapped on the surface of it. As the universe expands, the bubble just gets bigger.

We might not be the only bubble in the universe: there might be lots of them. When we look in the kitchen sink, we can see that bubbles can sometimes cut in half. In space, a black hole could cause this same effect. Once space has been sucked into a black hole, it might get blown out the other end as a white hole. From the side of the white hole, it looks just like a big bang. This means that there might be another universe being born on the other side of every black hole in our universe. A probe called LISA will be sent up into space and should detect the initial vibrations of the birth of the universe. LISA should also tell us which big bang theory is the best. Hopefully the answer will be that we were born of a mother universe, and we might be giving birth to others.

The membranes of these different universe bubbles might be very close to each other. Gravity can jump between the membranes but objects don't, so that's why we don't bump into things in parallel universes. The fact that gravity can jump between them means that we can detect other universes floating just above us. This is what the Hubble Space Telescope has done with dark matter: what it has seen could be the gravitational outline of the dark matter of a parallel universe.

The benefit of knowing about parallel universes is that it provides a possible escape from our universe. Our universe bubble is getting bigger and bigger and one day might explode. With enough energy, it would be possible to heat up space to levels similar to that of the big bang. This amount of energy would make space unstable and new bubbles to be formed. From there, we could go into another universe. It is just like Alice and the Looking Glass.

- What Happens When Moss Grows in Space

The Naked Scientists spoke to NASA scientist, Dr. Volker Kern Chris - You've been looking at how plants grow in space. Why?

What Happens When Moss Grows in Space
with NASA scientist, Dr. Volker Kern Chris - You've been looking at how plants grow in space. Why?

Volker - NASA has a number of new missions, including going back to the moon and maybe even Mars. If astronauts are sent out for long periods of time, they need something to feed themselves. Therefore, we have done a number of plant experiments on space flights to see how the plants respond to zero gravity. We decided to use roof moss because you can pinpoint individual cells and work out the growth mechanism. This is not possible in higher plants as they have millions of cells to look at.

Chris - What are the results so far?

Volker - After growing the moss in space for 14 days, we opened up the containers and found the moss growing in spirals. This is something we hadn't predicted. Originally we thought that it would grow randomly, just like other plants that have been taken into space. On earth, plants are guided by the force of gravity, which ensures they grow in the right direction. Taking gravity away means that they don't know which way to go. The experiments also show that light is not the most important aspect of making sure plants grow upwards. For example, when seeds send up their first shoots they are in the dark, so they only have gravity to guide them.

Chris - How does moss's spiral growth help you understand how plants grow when gravity is present?

Volker - We think the organelles settle in the cell, allowing the cell to know which way is down. I suppose it's quite like a spirit level. These experiments will also help with us to grow other plants in the future. We started with simple moss and can now do similar experiments with more complicated plants. Eventually, we hope to be able to grow lots of plants in space for hungry astronauts !

- Is There Life on Mars ?

The Naked Scientists spoke to Astrobiologist Dr Monica Grady Monica - The focus of my work is investigating life on Mars to find out whether it's there...

Is There Life on Mars ?
with Astrobiologist Dr Monica Grady Monica - The focus of my work is investigating life on Mars to find out whether it's there. There are other questions we also hope to answer: would life on Mars be the same as that

Chris - Do you think that the fossils found in meteorites from Mars might have been the start of life on Earth?

Monica - The fossils found in the meteorite were tiny and a huge amount of discussion has come out of it! What's more, only one such meteorite has been found. It is now thought not to be a fossil from Mars, but that is not very important. We know a lot of other things about Mars and it is this other evidence that leads us to think that Mars might have had life on it.

Chris - Could a life-form survive the journey from Mars to Earth?

Monica - Life would certainly perish if it floated by itself as it would be destroyed by the radiation of space. However, if it were buried under a small crust of ice or rock, it would be safe. A spore or something similar could have made it to Earth in this way and have been safe for hundreds of thousands of years. My gut feeling is that it didn't happen like this at all. I think life would have started on Earth and Mars separately.

Life started from chemistry and we know from looking at Earth the type of ingredients needed. These include carbon, water and a way of getting them together. There must be some stable platform for the building blocks to fit together on and some sort of protection from radiation, heat and pressure. This protection comes in the form of an atmosphere like we have on Earth, something found in few places elsewhere in the solar system. Mars had an atmosphere at one point but lost it. This is why we think there might have been life on Mars some time in the past. It could still be lurking somewhere beneath the surface.

Chris - What are the signs of life? What hallmarks can be used to pin point it?

Monica - The most important thing is that life metabolises: it breathes in, converts and breathes out again. During this conversion trace elements are produced, so when looking for life we look for trace gases...

- The Ingredients For Life And Earth-like Planets

The Naked Scientists spoke to Astronomer Dr. Simon Goodwin Simon - In my work we cast the net slightly wider than Mars and look for life outside our solar...

The Ingredients For Life And Earth-like Planets
with Astronomer Dr. Simon Goodwin Simon - In my work we cast the net slightly wider than Mars and look for life outside our solar system. We want to know what life there will be like and whether it is intelligent. The

Chris - Why are you interested in looking at planetary configurations?

Simon - There is only one planet we know that supports life, and this planet has certain things that are special to it. Firstly, Earth is the right distance away from the sun to have liquid water. Secondly, Earth has a very large moon. The fact it gives us tides might be quite important, but more important is that the moon stabilises the Earth's axis. Without the moon, the planet would flip every so often by twenty or thirty degrees. This can be caused by the gravitational effects of other planets. It wouldn't necessarily kill life off, but it certainly wouldn't be good for it! A flipping Earth could have serious problems, so having a large moon is a very fortunate arrangement.

Our solar system also has a massive comet hoover. As comets fly through the solar system, most are caught by Jupiter's gravitational field and stops them crashing into Earth. The last comet to hit Earth killed the dinosaurs, so without a huge planet like Jupiter nearby, life might not get going.

Chris - How many other solar systems are there?

Simon - Billions! The planets we have found so far are all similar to Jupiter, but hopefully we will find an Earth-like planet soon. Jupiter-like planets are easiest to find because they are big, but we have a suspicion that there must be more planets like Earth. Life is probably very common, but the big question is whether any of it is intelligent.

Chris - Are we far from being able to spot Earth-like planets?

Simon - We are close. At the moment, we can look for a slight eclipse in front of stars similar to the recent transit of Venus. We are building satellites to look for these dips. This means that so far, we have only seen the effect of planets on stars: an indirect way of seeing. Other ideas include looking directly at the light from Earth-like planets by blocking out the light from stars. Once can see light from a planet, we can look at its spectrum. The best possible outcome would be seeing ozone in this spectrum. This would indicate a large amount of oxygen, and for this much oxygen, we need life!

- Why did stopping antidepressants leave me unable to sleep?

I stopped taking antidepressants a while ago. After two weeks I couldn't sleep all night and then wouldn't be tired in the day. My doctor...

Why did stopping antidepressants leave me unable to sleep?

I have to admit that I haven't heard of this. Some antidepressants stimulate appetite and a lot of the food we eat can be sweet things. This packs an energy punch which may cause you to stay awake. Other than that, I have to say that I'm as mystified as your doctor on this one!

- Is it possible that life on Mars managed to hitch a ride on a meteorite and started life on Earth?

Is it possible that life on Mars managed to hitch a ride on a meteorite and started life on Earth?

Is it possible that life on Mars managed to hitch a ride on a meteorite and started life on Earth?

We think that conditions on the early Earth were very bad for life as there was no atmosphere. Mars might have been a better place to live at that time, and so life could have started there but we just don't know. To find out if life really did get going on Mars, we need to go there and have a look.

- If a meteorite hit the earth, could life be blown onto other planets?

If a meteorite hit the earth, could life be blown onto other planets?

If a meteorite hit the earth, could life be blown onto other planets?

You need to travel at 11 metres per second to escape form Earth's gravity. It is much harder to blow things off the Earth than it is Mars, although it is potentially possible to go from Earth to Mars. Humans might even be doing it accidentally when we send satellites up into space: sometimes they get hit with things and things like paint might flake off. However, once above the atmosphere, everything we send up is sterilised by radiation. And space scientists do as much as they can to prevent space becoming contaminated.

- Will future time-travelling humans come back to visit us?

Do you think it's possible that future man could have conquered time travel and be coming back to look at us?

Will future time-travelling humans come back to visit us?

Anything is possible. There are a number of theories about how we can travel through time but they usually involve going into the future using the theory of relativity. Essentially, this involves going so fast that your body clock slows down. When you stop moving so quickly, everything around you will have aged but you will be only a little bit older. In this way, you are able to travel into the future. Another method that has been suggested is to go to a black hole and go out the other end of it. Stephen Hawking doesn't believe time travel is possible because we would have seen people from the future if it were true. A lot of equations in physics don't work backwards, so going back in time seems unlikely. It would be very difficult.

- Could bomb testing make the world fall apart or cause tsunamis?

Could bomb testing make the world fall apart or cause tsunamis?

Could bomb testing make the world fall apart or cause tsunamis?

I think it is very unlikely. The energy needed to cause something like a tsunami is huge, and to make the world fall apart it would need to be even bigger. It might be possible to cause a tsunami if a bomb was planted in a particular place and the Earth's plates moved. This would require considerable planning, so a tsunami shouldn't be caused by bomb testing, unless it was many times bigger than Hiroshima and Nagasaki.

- If there are parallel universes, do you think Elvis might still be alive and making hits in another ?

If there are parallel universes, do you think Elvis might still be alive and making hits in another?

If there are parallel universes, do you think Elvis might still be alive and making hits in another ?

It's an interesting question! I suggest you go along to Michio's talk at Naked Science on Tuesday and find out!

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