September 28, 2018



Scientific Objectives

The scientific objectives of Hayabusa2 mission are twofold:

  • To characterize the asteroid from remote sensing observations (with multispectral cameras, near-infrared spectrometer, thermal infrared imager, laser altimeter) on a macroscopic scale
  • To analyse the samples returned from the asteroid on a microscopic scale.

In addition, the scientific objectives of MASCOT/Hayabusa2 as defined by the science team are:

  • To accomplish context science to complement the remote sensing observations from Hayabusa2,
  • To provide ground truth information down to the microscopic scale for the sample analyses,
  • To accomplish stand-alone science that only a lander can provide e.g. geophysics investigations,
  • To serve as a "scouting" vehicle to guide the sampling site selection of the main spacecraft.

 Müller et all, 2011.
Model of the shape of the asteroid Ryugu: Müller et all, 2011.

MicrOmega with its in-situ mineralogical analysis capacity of the asteroid's soil answers to one of MASCOT/Hayabusa2's main scientific objective and should allow us to find hydrated and carbonated minerals, which is fundamental to understanding the origin of the asteroid Ryugu.

Image and spectra of a sample of pyroxene, kaolinite and nontronite, performed with the MicrOmega prototype
Image and spectra of a sample of pyroxene, kaolinite and nontronite, performed with the MicrOmega prototype:
pyroxene (1, blue) ; nontronite (2, green) ; kaolinite (3, red)

We must remember that enough small sized objects of our Solar system have not been submitted to major transformation since their formation. It is probably true for Ryugu.

In this context, all we will learn from the mineralogical analysis of this asteroid will be a determining key to a better knowledge of our Solar System in its primitive state, to understand how it was born, was formed, has evolved and to get closer to the original materials when life appeared on Earth.

In addition, the in situ mineralogical analysis will contribute to the overall scientific feedback to the Hayabusa2 mission enabling:

  • to offer a "ground truth" to the global characterization from Hayabusa2's remote sensing observations,
  • to serve as reference to the analyses of the samples that will be brought back to Earth. Indeed, they will enable to verify if the collect process, and/or return on Earth, introduced bias in the properties of the returned samples, for example for the size distribution or the composition. For the first time, it will be possible to verify the representativeness of extraterrestrial samples analyzed in laboratory.


The Hayabusa2 mission benefits from a large inheritance from Hayabusa1, mission launched in 2003 towards a S-class asteroid (Itokawa), for a sample return to Earth in June 2010.

In the same way, MASCOT/Hayabusa2 benefits from the Philae/Rosetta mission inheritance (launch in 2004, arrival on the comet in summer 2014) and from the studies carried out for the Marco Polo mission of the ESA's Cosmic Vision program.

In this context, despite a passage in phase B of the Hayabusa2's project in May 2011, and of MASCOT/Hayabusa2 at the beginning of 2012, the 2014/2015 launch objective was realistic.

Key dates for MASCOT/Hayabusa2 mission:

  • Launch: December 3, 2014 by H2A (version H2A202-4S) from Tanegashima Space Center
  • Arrival at the asteroid and beginning of the exploration mission from the probe: mid-2018
  • MASCOT Separation/Landing: October 2018 for a 12 hours mission
  • Sampling: Two sites visited
  • Departure from the asteroid: December 2019
  • Go back to Earth: December 2020


Hayabusa2  trajectory and MASCOT separation
Credits JAXA