Question Mars' daylight

[Space Seeker]

How long do the daylight hours change monthly throughout a Mars' year near Mars' South Pole by Earth time?

 

[COLGeek]

Because of the planet's tilt, similar to Earth, I would assume seasonal daylight changes similar to ours. However, the Martian year and seasons are longer than ours (number of days to circle the Sun), so the daylight changes would follow suit.

What specifically are you trying to determine?

 

[Pogo]

It would be like the Earth’s year, but, twice as long, but, sunlight is about half what it is here because of the distance from the Sun. The day is about a half hour longer.

 

[Space Seeker]

It would be like the Earth’s year, but, twice as long, but, sunlight is about half what it is here because of the distance from the Sun. The day is about a half hour longer.

Thank you for your reply. Considering the thinness of the atmosphere on Mars, how much stronger will the sunlight be on Mars's surface than on Earth?

 

[Space Seeker]

Because of the planet's tilt, similar to Earth, I would assume seasonal daylight changes similar to ours. However, the Martian year and seasons are longer than ours (number of days to circle the Sun), so the daylight changes would follow suit.

What specifically are you trying to determine?

Thank you for your reply. I personally want to simulate growing plants on Mars, so I'm looking into the yearly variation of daylight hours in the most watery Antarctic.

 

[billslugg]

In the Antarctic of mars there is perpetual darkness in their winter. There is no sunlight. In summer it is perpetually light but at a strength only about 40% of ours. Without an atmosphere, Mars doesn't lose 30% like Earth does. Mars net sunshine on the surface would be about half that of Earth.

 

[Space Seeker]

In the Antarctic of mars there is perpetual darkness in their winter. There is no sunlight. In summer it is perpetually light but at a strength only about 40% of ours. Without an atmosphere, Mars doesn't lose 30% like Earth does. Mars net sunshine on the surface would be about half that of Earth.

Thank you for your reply. So, apart from the temperature, sunlight would be insufficient to grow plants in the Antarctic region of Mars?

 

[Classical Motion]

I wonder how pressure effects growth. We know plants can take higher pressure for we have marine plants. And plants can grow at high altitudes. But how much of the green line is pressure related as well as temperature related. Or CO2 related.

Does water preform the same at low pressures? How much external pressure is needed for life? There must be a pressure band with the temperature band.

Marine based life can exist under very high pressures. But is there a minimum pressure for life?

It seems that water bears and some rotofers can survive no pressure. But could a seed spout and grow?

Is pressure also a requirement for life?

 

[Space Seeker]

I wonder how pressure effects growth. We know plants can take higher pressure for we have marine plants. And plants can grow at high altitudes. But how much of the green line is pressure related as well as temperature related. Or CO2 related.

Does water preform the same at low pressures? How much external pressure is needed for life? There must be a pressure band with the temperature band.

Marine based life can exist under very high pressures. But is there a minimum pressure for life?

It seems that water bears and some rotofers can survive no pressure. But could a seed spout and grow?

Is pressure also a requirement for life?

Thank you for the enlightening reply. What about starting with growing algae like chlorella or spirulina in farms or tubes?

 

[billslugg]

Mars has only half the sunlight of Earth. If growing with solar energy, the best way might be to put out solar panels, get the sunlight into the form of electricity and then put the plants underground with grow lights that put out only the needed wavelengths. Typically a narrow line in the blue and one in the red. The growth rates would be higher than simply exposing the plants to sunlight.

 

[Space Seeker]

Mars has only half the sunlight of Earth. If growing with solar energy, the best way might be to put out solar panels, get the sunlight into the form of electricity and then put the plants underground with grow lights that put out only the needed wavelengths. Typically a narrow line in the blue and one in the red. The growth rates would be higher than simply exposing the plants to sunlight.

Thank you for sharing your wonderful insight. Underground cultivation is also likely to protect plants from radiation. Can there be the nutrients necessary for plants, such as nitrogen, phosphorus, and potassium, in the soil on Mars?

 

[billslugg]

Mars has a tiny bit of nitrogen in the atmosphere, the other elements present in trace amounts. Humans may need to take their fertilizer with them. It can be recycled easily by composting.

 

[Space Seeker]

Mars has a tiny bit of nitrogen in the atmosphere, the other elements present in trace amounts. Humans may need to take their fertilizer with them. It can be recycled easily by composting.

Thank you. I see, that recycling plant nutrients through composting is great. Is it possible to use excess chlorella and spirulina from hydroponic cultivation as raw material for compost for lettuce or barley?

 

[billslugg]

Carbon is carbon. Any material that was once alive can be composted. I suspect that hydroponics would prevail, but how do we use compost in hydroponics? Doesn't make sense.

 

[Space Seeker]

Carbon is carbon. Any material that was once alive can be composted. I suspect that hydroponics would prevail, but how do we use compost in hydroponics? Doesn't make sense.

I like to imagine simulations of space immigration, and I think that space cultivation of plants is an important prerequisite for space immigration.
Starting with chlorella and spirulina, which are easy to grow hydroponically and highly nutritious, composting the surplus algae will likely be effective in expanding to cultivate higher plants such as vegetables.

 

[billslugg]

If algae is easy to grow but not tasty, perhaps we could feed it to algae eating fish rather than make it into dirt.

 

[Space Seeker]

If algae is easy to grow but not tasty, perhaps we could feed it to algae eating fish rather than make it into dirt.

You're right.
Algae seem to be the easiest to produce basic nutrients in space. However, more advanced plants, and other animals than humans will also be necessary to maintain a culture in space. Feeding them the algae surplus for humans may be valid.
When considering the effort and cost required to raise tasty fish in low gravity, isn't soy-based artificial meat more realistic for the time being?

 

[billslugg]

You're right.
Algae seem to be the easiest to produce basic nutrients in space. However, more advanced plants, and other animals than humans will also be necessary to maintain a culture in space. Feeding them the algae surplus for humans may be valid.
When considering the effort and cost required to raise tasty fish in low gravity, isn't soy-based artificial meat more realistic for the time being?

The premise was the ease with which algae is grown but how nasty it is to eat. I'm trying to bridge that gap. Bringing soybeans into it makes it harder. It should be as simple and efficient as possible.

 

[Space Seeker]

The premise was the ease with which algae is grown but how nasty it is to eat. I'm trying to bridge that gap. Bringing soybeans into it makes it harder. It should be as simple and efficient as possible.

Thank you for your wise knowledge.
How about Euglena? Euglena is likely the best feed for grass carp, Ctenopharyngodon idellus or crucian carp, Carassius cuvieri. Euglena can be cultivated using light. Moreover, it can be used as an ingredient in space food.