BepiColombo’s First Views of Mercury

[cletus]

I see a bunch of confusion about Mercury in this thread so let me correct the record.

First, as to why colonize Mercury, there are some really good reasons:

1. Cheap, abundant energy (ie solar);

2. Access to tons of raw materials, particularly metals;

3. Relatively low gravity means getting into orbit is relatively low cost.

A few people have stated we'd hide in a crater as a negative. We'd live underground probably in submerged habitats that spin to produce Earth-like gravity, just as we would have to on Mars and the Moon.

For Mars in particular, people have this romantic notion of living on the surface. We wouldn't. There's essentially no atmosphere. Worse than no atmosphere actually there's just enough to cover all your gear in dust and do little else for you. You still have to worry about radiation. Terraforming is a monstrously massive project that would take millenia.

The biggest negative to Mercury is how hard it is to reach from Earth. Fun fact: the delta-V required to reach Mercury from Earth is more than that to escape the Solar System (eg like New Horizons). There's a reason this probe is taking 7 years to get there and doing multiple gravity brakes along the way (watch the ESA animation [1]).

If you're going to bootstrap a Dyson Swarm, Mercury is almost the perfect place to do it from.

[1]: https://www.esa.int/ESA_Multimedia/Videos/2017/07/Animation_...

[Loughla]

Two things from that video:

1. The amount of planning that is required for this is just astounding to me. That we can pretty trivially plan to use something like planetary motion as a motor is fascinating.

2. I'm really bad at Kerbal Space Program.

[bartvk]

This is a great mission for mankind as well. A previous HN discussion talked about the possibility of a Mercury colony because it has water ice.

https://news.ycombinator.com/item?id=27741738 https://www.universetoday.com/128531/terraform-mercury/

[lmilcin]

Except colonizing Mercury is of relatively little value because of how little surface of it is usable, impossibility of terraforming the planet, how difficult it is to get there or back and that it does not help to reach any other interesting place in our system or outside of it.

[entrep]

Here's a great overview of BepiColombo's journey: https://www.esa.int/Science_Exploration/Space_Science/BepiCo...

[pietroppeter]

> BepiColombo is named after Giuseppe "Bepi" Colombo (1920–1984), a scientist, mathematician and engineer at the University of Padua, Italy, who first proposed the interplanetary gravity assist manoeuvre used by the 1974 Mariner 10 mission, a technique now used frequently by planetary probes.

https://en.m.wikipedia.org/wiki/BepiColombo

[davidw]

I saw that name and I thought "that's a name from the Veneto".

The history of that university is pretty amazing. I can't recommend the tour enough, if people go through Padova. It's a nice change from all the churches, castles and villas that you see elsewhere in Europe.

https://en.wikipedia.org/wiki/University_of_Padua

[ddevault]

https://en.wikipedia.org/wiki/BepiColombo

[harscoat]

To see how bare the planet is, with so many cosmic impacts… makes us wonder how fragile a planet with life is

[lmilcin]

I am no expert, but I think it is very likely most of these craters are from very early life of the planet, before there was life on Earth. Orbit of Mercury is very well cleaned of any other bodies and must have been like this for billions of years.

Because there is no erosion mechanism on Mercury (except for crumbling due to temperature changes) these craters were preserved perfectly.

[TedDoesntTalk]

> BepiColombo’s main science mission will begin in early 2026. It is making use of nine planetary flybys in total: one at Earth, two at Venus, and six at Mercury, together with the spacecraft’s solar electric propulsion system, to help steer into Mercury orbit. Its next Mercury flyby will take place 23 June 2022.

What a strange mission. Why can’t it stay in orbit around Mercury now?

[gorgoiler]

We live in a village at the top of a very steep, mile deep, ice covered valley. Mercury is a village at the bottom of the valley.

Your house is high up the valley but you actually live thirty feet deep in a pit. To get to Mercury you have to build a car, lift it out the pit, then slide down the steep valley. The car has to be lightweight so that you can lift it out the pit: the engine and brakes are weak and do next to nothing.

So you build a feeble car — more of a four wheeled bicycle really, hoist it out the pit, and slide down the valley in it. By the time you whizz past Mercury you’re doing 100mph so you can’t stop. You go straight past and start sliding up the other side, but you do also put the brakes on for a bit. You’ll eventually slide back down to Mercury again at 90mph and put the brakes on again, and slow down a little more.

Do this ~10x and you’ll eventually stop.

Going in the other direction is easier. Earth is surrounded in a 100km soft squishy cushion of gas which means to all intents and purposes you can just fly straight at it.

[microtonal]

The Wikipedia page has a nice description of the issues of entering Mercury's orbit:

https://en.wikipedia.org/wiki/Mercury_(planet)#Research_with...

[arethuza]

It's going too fast and doesn't carry enough fuel to slow down directly into orbit.

[brylie]

By way of example, here is a video explaining what was needed to get the Messenger spacecraft into orbit around Mercury:

https://youtu.be/gBwspxfW10w

[brylie]

Here is an example of a rocket design/mission in Kerbal Space Program that can insert into orbit on the first pass:

https://youtu.be/lYwrbhzj694

[adolph]

The closest approach took place at 23:34 UTC on 1 October at an altitude of 199 km from the planet’s surface.

[noizejoy]

Albeit the pictures are from at least 1000 km away, since closest approach was from the dark side.

[jcims]

I’m always amazed at the precision of space probe operations.

It’s a bummer we don’t have better space propulsion systems, five years meandering about the inner solar system to get the right speed and angle to enter an orbit around mercury.

[jrootabega]

This is an amazing achievement.

Also, there appears to be a typo in one of the images near the bottom. "Lemontov" instead of "Lermontov".

[_boffin_]

> comets crashing onto the surface at speeds of tens of kilometers per hour.

comets came crashing down slower than one goes in a school zone?

[ladberg]

For anyone else reading, it's since been updated to "tens of kilometers per second."

[pengaru]

This is cool and all, but why am I looking at black and white photos in 2021 sent from something launched in 2018?

[stiller]

The images were taken using the monitoring cameras:

https://www.esa.int/ESA_Multimedia/Images/2018/10/BepiColomb...

Images using primary instruments will follow when it reaches orbit in 2025.

[SiempreViernes]

It's a navigation camera, not output from any main instrument so it doesn't come with a filter wheel. The importance factor is having very good linear response to incoming light, not making good phone backgrounds.

[Fronzie]

Because it's a scientific instrument and there's surprisingly little science value in capturing the other visible-light wavelengths.

[m4rtink]

Does the surface of Mercury actually show any perceptible color or is it just basically grayscale like the Moon ?