According to Dr Karl in his latest book, Short Back and Science, NASA is launching a solar-orbiter spacecraft in 2018 which will come within 25 million kms of the Sun. According to the internet, it will only be that close to the Sun every 5 months.
How will the instruments be protected during the 7 year mission? is this the closest a spacecraft has ever been to the Sun?
http://sci.esa.int/solar-orbiter/44168-spacecraft/
the ESA probe
http://solarprobe.jhuapl.edu
NASA probe
http://analprobe/TTB/20151111-18015.edu
ANAL Probe
Well that went south quickly.
there’s been a disturbance in the force
it’s like mud in here.
2018 is the launch year for the ESA’s solar orbiter, which will indeed go closer to the sun than any previous craft, about 47 million km.
NASA’s Solar Probe Plus launches in the same year but will arrive in final orbit in 2024. It will pass about 8 million km from the sun.
I do not know what kind of special engineering is being carried out in terms of heat shielding.
Eight weeks after launch, Solar Probe Plus will arrive at the sun to begin the first of 24 orbits using flybys of Venus to gradually shrink its distance to the sun. Eventually, it will come as close as about 4 million miles, which is inside the orbit of Mercury and about eight times closer than any previous spacecraft.
http://news.discovery.com/space/history-of-space/solar-probe-plus-sun-corona.htm
so according to the above the closest any spacecraft has come is 32 million (ugh) miles.
reading the articles looks like non-ablative carbon fibre heat shields. they don’t want particles coming off to interfere with the probes instruments.
ChrispenEvan said:
Eight weeks after launch, Solar Probe Plus will arrive at the sun to begin the first of 24 orbits using flybys of Venus to gradually shrink its distance to the sun. Eventually, it will come as close as about 4 million miles, which is inside the orbit of Mercury and about eight times closer than any previous spacecraft.http://news.discovery.com/space/history-of-space/solar-probe-plus-sun-corona.htm
so according to the above the closest any spacecraft has come is 32 million (ugh) miles.
Yes they were the Helios crafts.
Of course by the time SPP reaches close orbit in 2024, the Helios record will have already have been beaten by the ESA Solar Probe.
ChrispenEvan said:
reading the articles looks like non-ablative carbon fibre heat shields. they don’t want particles coming off to interfere with the probes instruments.
Sure. As well as heat, there’s also particles flying everywhere. I think it’s a safe bet we’ve learned from the mythological Icarus and they’re not using wax.
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.
What are they looking for, water?
Peak Warming Man said:
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.What are they looking for, water?
Stars make water, among other stuff
Peak Warming Man said:
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.What are they looking for, water?
Safe landing spots
dv said:
Peak Warming Man said:
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.What are they looking for, water?
Safe landing spots
They’d land at night, of course.
Peak Warming Man said:
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.What are they looking for, water?
When you’re looking for a material of low thermal conductivity, it’s very difficult to beat open space. Thermal conductivity is zero. But there’s no resistance to thermal radiation.
A while back I designed what I consider to be the ultimate lightweight heat shield for space applications. I’ll try to find it. Multiple layers were used, the hottest layer is of either carbon or tungsten, I can’t remember which right now. From memory it only took about 4 layers to reduce temperatures from hot enough to melt ceramics all the way down to sub-zero.
“When you’re looking for a material of low thermal conductivity, it’s very difficult to beat open space. Thermal conductivity is zero. But there’s no resistance to thermal radiation.”
Open space is not very good for making structural components.
mollwollfumble said:
Peak Warming Man said:
A reflective shield supported by material with a low coefficient of thermal conductivity material should do the trick.
Deployed after launch obviously.
Also a the heat shield would need to be designed so as not to interfere with the passive instruments harvesting data.What are they looking for, water?
When you’re looking for a material of low thermal conductivity, it’s very difficult to beat open space. Thermal conductivity is zero. But there’s no resistance to thermal radiation.
A while back I designed what I consider to be the ultimate lightweight heat shield for space applications. I’ll try to find it. Multiple layers were used, the hottest layer is of either carbon or tungsten, I can’t remember which right now. From memory it only took about 4 layers to reduce temperatures from hot enough to melt ceramics all the way down to sub-zero.
Here’s what I wrote before:
————————————
Heat shield
There needs to be a heat shield between it and all other equipment. It turns out that the heat shield is remarkably easy to design. The heat shield can consist of just three layers each separated by a vacuum. The layers can be allowed to touch one another at just enough points for structural integrity. The vacuum of space ensures that the heat transfer between the layers is by radiation.
The heat impinging on the heat shield is the hottest part of the whole craft. Let’s suppose it has a temperature of 2400 K. This heat encounters the hot-facing side of the first layer of the heat shield, whose surface is mirror-reflective tungsten. Bonded to that, on the cold-facing side of the first layer of heat shield is carbon. Opposite that is the hot-facing side of the second layer of the heat shield, whose surface is mirror-reflective molybdenum. Bonded to that, on the cold-facing side of the second layer of heat shield is carbon. The final third layer of the heat shield can be made from gold, silver or aluminium.
Each layer only needs to be as thick as is needed for structural strength, the thermal conductivity of the layers is irrelevant.
Calculated temperatures of the temperatures of the three layers of heat shield are 1707 K for the first layer, 666 K for the second layer, and 185 K for the third layer. This final temperature is at least as cold as necessary. In doing this calculation, the reflectivities of gold & silver are taken to be 99.5%, of molybdenum 98.5%, of mirror-finish tungsten 98%, and of carbon 16.5%.
Depending on the neutron flux, the materials of the heat shield can be either natural tungsten and molybdenum or isotopically pure 184W and a mixture of 94Mo and 92Mo. I recommend the latter.
APL is designing and will build the spacecraft, on a schedule to launch no later than 2018. The compact, solar-powered probe would weigh about 1,350 pounds; preliminary designs include an 8-foot-diameter, 4.5-inch-thick, carbon-carbon carbon foam solar shield atop the spacecraft body. The solar arrays will retract and extend as the spacecraft swings toward or away from the Sun during several loops around the inner solar system, making sure the panels stay at proper temperatures and power levels. At its closest passes the spacecraft must survive solar intensity more than 500 times what spacecraft experience while orbiting Earth.
http://solarprobe.jhuapl.edu/mission/
and the ESA Probe
http://www.esa.int/Our_Activities/Space_Engineering_Technology/Prehistoric_cave_pigment_to_shield_ESA_s_Solar_Orbiter