Japanese lunar lander begins its descent
Japanese space agency officials say the probe has begun its powered descent.
The process should take 20 minutes.
Live data is being sent from the spacecraft to earth, although there is no live video feed.
Key events
The Slim lander is 5 km above the moon’s surface.
We are in the “vertical descent” mode, the final part of the landing process.
Five minutes until landing
Slim’s engines have started firing again to slow it down before touchdown
Once its touches down, the Slim landing craft is going to tip over … but that is part of the plan.
The landing site is near a crater and therefore has a 15 degree slope, the Japanese space agency says.
Therefore, the lander has a “two-step landing method”, in which the main landing gear first touches the ground and then rotates forward to stabilise itself.
Here is what it should look like:
Officials say the trajectory of the spacecraft is matching what was planned (a good sign)
(I’m really enjoying the soft piano music being played in the background of this Japanese space agency live feed. Very calming in a tense situation!)
The probe is now “scanning the surface” and looking for a place to land, space agency officials say.
The two robots on board the probe
Ian Sample
Our science editor, Ian Sample, has some more info on the two robots onboard the spacecraft:
Here’s a little more on what are called the rovers, but should probably have called “lunar excursion vehicles” – one doesn’t so much rove as hop:
The Slim lander carries a couple of quirky “lunar excursion vehicles’’, or Levs, that will hopefully travel around on the moon’s surface, taking measurements and snapping pictures of the lander and its landing site.
Known as Lev-1 and Lev-2, they are both palm-sized robots that should be released by Slim shortly before touchdown. Rather than driving over the surface, Lev-1 is designed to hop around and take measurements with an onboard thermometer, radiation monitor and slope sensor.
The second, a ball-shaped mini-rover designed with Takara Tomy, the toy firm behind Transformers, uses the same shape-changing technology to pop open, revealing two cameras and turning the two hemispheres into wheels. The hope is for the vehicles to hop and trundle over the surface for the couple of hours that their battery life allows.
Japanese lunar lander begins its descent
Japanese space agency officials say the probe has begun its powered descent.
The process should take 20 minutes.
Live data is being sent from the spacecraft to earth, although there is no live video feed.
The powered descent (which will start in about 10 minutes) will begin from 15 km above the lunar surface, Japnese space agency officials say.
The vertical descent will start at 7 km.
Just before landing, at 2 metres, the probe will release two small rovers.
In this livestream, Japanese space agency officials are referring to a “rabbit” on the moon.
While people in the west see the image of a face on the moon, in East Asia people have long seen the shape of a rabbit instead!
How the probe will make such a precise landing
Ian Sample
Our science editor, Ian Sample, has some fascinating details on how the probe plans to make such a precision landing:
There’s more to this mission than simply joining the soft lunar landing club.
The aim is to demonstrate technologies that future missions will need to land precisely where they need to. Until now, space agencies have been happy for landers to touchdown anywhere in an area a few km square – they’ve just gone for the safest options.
But this probe is hoping to demo technologies that give you more pinpoint landings which is going to be important – if you want to mine a certain crater, you don’t want to land 5km away, you want to land right next to it.
This probe has similar AI to that used in facial recognition which it’ll use to recognise patterns of craters on the moon as it flies over. This then feeds into the lander’s calculations for trajectory and engine burns.
Shin Toriumi, from the Japanese space agency, Jaxa, says the descent phase of the lunar lander (happening in about half an hour) is known internally as “20 minutes of terror”.
You’ll see above we have a live video feed from the Japanese space agency to take us through the landing.
It is being hosted by Shin Toriumi from the Institute of Space and Astronautical Science at the Japan Aerospace Exploration Agency, Jaxa.
Opening summary
Oliver Holmes
A Japanese spacecraft is en route to the moon on a mission prove a highly precise landing can be made on the lunar surface.
In about 30 minutes, the probe – dubbed the “moon sniper” for its accuracy – will begin its descent. It aims to make a “soft” and safe landing within the next hour.
If successful, the Smart Lander for Investigating Moon (SLIM) will make Japan the fifth country to touch down safely on the lunar surface. The Japan Aerospace Exploration Agency (Jaxa) hopes pinpoint technology will put the lightweight craft down less than 100 metres from a predetermined target on the moon’s surface – a dramatic improvement on previous missions, in which the landing zones measured several kilometres.
Jaxa officials say the moon sniper is a “technology demonstrator” that will provide vital information for future crewed missions, and the eventual establishment of moon bases. Slim also carries instruments that will aim to “unravel the origins of the Moon” by analysing lunar rocks, Jaxa says.
Oliver Holmes here. I’ve be your guide today as Japan seeks to move the human race another step closer to building a permanent presence on our nearest neighbour, only 380,000 km (239,000 miles) away.