The Japan Aerospace Exploration Agency (JAXA) on Monday made a second attempt to put the Akatsuki probe into orbit around Venus.
"It is very much expected to enter the planned orbit," JAXA professor Masato Nakamura, who is in charge of the Akatsuki programme, said.
With the nozzle of the probe's main engine apparently wrecked, JAXA reprogrammed Akatsuki to use four thrusters for an attitude-control burn to send it into an elliptical orbit of upto 300,000 km and eight to nine days long around Venus, giving it two years to observe the planet's meteorological phenomena.
JAXA will confirm on Wednesday whether the manoeuvre succeeded or not.
Carrying six types of observation equipment, Akatsuki is designed to study the thick clouds shrouding Venus in three dimensions and how its strong winds, estimated to be faster than 360 kph, cause an atmospheric phenomenon known as super-rotation, in which the atmosphere rotates much faster than the planet.
The probe was launched in May 2010 by an H-IIA rocket. After failing to achieve orbit around Venus, JAXA let the probe orbit the sun and adjusted its path in 2011 and this year to prepare for Monday's second attempt.
Despite being exposed to more heat and radiation from the sun than it was designed to withstand, no damage has so far been detected to Akatsuki's equipment.