The Japan Aerospace Exploration Agency plans to launch a new large-scale test rocket in fiscal 2020 and another the following year.

The rocket, provisionally dubbed H-III, is a successor to JAXA's H-IIA launch vehicle.

According to JAXA's plan, reported to a science ministry panel Tuesday, the H-III will basically have two engines in its first stage and have no solid-fuel boosters.

In the first test in fiscal 2020, JAXA plans to launch an H-III with a satellite to be put into a polar orbit at an altitude of several hundred kilometers.

In the second test in fiscal 2021, the agency will add boosters to an H-III rocket to place a satellite into a geostationary orbit some 36,000 km above the equator.

Since Mitsubishi Heavy Industries Ltd. has taken over launching the H-IIA and H-IIB rockets from JAXA, the company is expected to be appointed the main manufacturer of the H-III by the end of the current fiscal year to March.

The agency plans to cut manufacturing costs for H-II engines, which burn extremely low-temperature liquid hydrogen and liquid oxygen, by simplifying pipes and pumps to make them more reliable.

It will also develop solid-fuel boosters that can be attached to an H-III in different numbers according to the satellite the rocket carries.

JAXA hopes to halve rocket launch costs from around Yen 10 billion for the H-IIA to Yen 5 billion to Yen 6.5 billion for the H-III.