June 7, 2014
ESA To Begin Providing Regular Space Weather Forecasts For Venus Express Probe
redOrbit Staff & Wire Reports - Your Universe Online
Now that the European Space Agency’s (ESA) Venus Express spacecraft has completed its eight-year scientific mission and is preparing to plunge into the planet’s atmosphere, the agency has started providing regular space weather reports for an extraterrestrial world for the first time.
Venus Express, which was launched in November 2005, had been orbiting the planet in an elliptical 24-hour loop and using a suite of seven instruments to create a comprehensive study of its ionosphere, atmosphere and surface. Last month, however, it completed its mission and started descending into the world’s hostile atmosphere.
Since then, ground controllers flying the vehicle have been receiving daily reports on solar activity from experts at the agency’s Belgium-based Space Weather Coordination Centre (SSCC). As the agency explained in a statement, the scientists need to know what’s taking place on the Sun in real time, since solar activity can have an impact on the planet’s atmospheric density and radiation environment, which in turn affects the spacecraft’s trajectory.
The center was established by the ESA’s Space Situational Awareness (SSA) program office in 2013, and it has been delivering space weather services for Earth-based clients over the past year. Now that the Venus Express has wrapped up its primary mission, however, the reports have taken on a new importance, since the ground control team can take the satellite through a several-week-long ‘aerobraking’ campaign.
[ Watch the Video: ESA’s Venus Express Aerobraking Maneuver ]
“Aerobraking means lowering the spacecraft so that for part of each orbit it dips down very low and skims through the very uppermost reaches of the Venusian atmosphere,” explained Deputy Spacecraft Operations Manager Adam Williams. “We know that the current state of our Sun can affect Venus’ atmosphere, which could in turn impact the planned orbit of Venus Express as it passes through the atmosphere.”
Williams added the team does not expect they will have to replan any of their currently scheduled aerobraking orbits due to typical levels of solar activity. However, he noted the space weather reports will allow them to better understand “anomalous behavior that we may subsequently observe on the spacecraft, and in extreme cases, we would be more ready to react to a serious situation.”
For instance, they could change their plans if the agency’s startrackers became overloaded by radiation. The weather updates will include the most accurate and up-to-date information for several different sources, including the Proba-2 and other solar-orbiting ESA and NASA spacecraft, and transmit it to the control team as quickly as possible.
“The aim is to report on current conditions and give a short-term forecast of solar activity and radiation conditions, tailored for Venus,” said SSA team member Juha-Pekka Luntama. “We’re used to doing this for Earth-orbiting spacecraft, but it’s quite a challenge for Venus due to both its location and the complexity of that planet’s environment.”
[ Watch the Video: What’s Causing Crazy Weather On Venus? ]
“Venus is currently 59 degrees ahead of Earth on its orbit around the Sun, and we do not have a spacecraft between the Sun and Venus as we have for Earth,” Luntama added. “So, we need to adapt and extend space weather forecasts we regularly provide towards the direction of Venus.”
The first space weather report for Venus was issued on May 19, and included forecasts and analysis based on data obtained both from the solar-orbiting vehicles and a recently-established Earth-based network of Expert Service Centers that are operated by ESA member states in the SSA program, the agency said.
According to Luntama, there are plans to expand the network later on this year to include space weather information for missions traveling to other regions of the Solar System. That data will be provided by the Heliospheric Weather Expert Service Center. For now, though, the SSCC will continue to deliver daily reports to the Venus Express team.
“We’ll also issue special bulletins during the day if there is a significant solar event that might affect the Venus space environment,” Luntama noted. “If we’ve learned anything about forecasting space weather, it’s that there can always be surprises we were not able to predict.”
Image 2 (below): This image is part of the Venus space weather report issued 5 June 2014. During May-August 2014, ground controllers flying ESA's Venus Express will receive daily reports on solar activity issued by experts at ESA’s Space Weather Coordination Centre (SSCC), at the Space Pole in Belgium. The weather updates will deliver the best information from a variety of sources – including ESA’s Proba-2 and solar-orbiting ESA and NASA spacecraft – to the control team as rapidly as possible. Credit: ESA