Kepler Entered Mode on April 6
According to an update of April 8 from Charlie Sobeck, mission manager at NASA’s Ames Research Centre in Moffett Field, California, Kepler seemingly entered the mode on April 6. Kepler had burnt more of its dropping supplyof fuel in an emergency mode, which is essential to ignite its thrusters and position the spacecraft in communicating with Earth.
The turning manoeuvre which would have begun the new planet hunt had not yet been executed by the spacecraft. Kepler, till now had discovered planets by observing the slight dimming of starlight triggered by an orbiting planet that passed in front of a star. The investigation has been enthusiastically successful, discovering over 1,040 confirmed planets as well as more than 4,700 planet candidates since the launch of 2009.
The new campaign is said to have run from April 7 to July 1 and it would have looked out for the temporary brightening of star due to a different effect known as gravitational microlensing. The gravity of an intervening object, in microlensing, like in the case of planet, tends to focus and intensify the light from a background star, causing it to brighten.
Microlensing Targets Big Planets at Great Distances
Contrasting to Kepler’s other discoveries that seem to be smaller planets comparatively close to their host stars, microlensing tends to target big planets at great distances from their stars or even lonely planets seem to bewandering on their own through the depth of space. Ground-based telescopes have revealed 46 planets through microlensing and the astronomers expect that Kepler would discover 10 or more during the campaign.
These kinds of discoveries would be helpful in narrowing the statistics on how common free-floating planets could be throughout the Galaxy. Astronomers have synchronized an intricate plan wherein around two dozen ground-based telescopes that have been spread across six continents, would be gazing at the same area of the sky at the same time as Kepler.
They comprise the Optical Gravitational Lensing Experiment – OGLE survey that tends to hunt for microlensing events from the Las Campanas Observatory, in Chile. OGLE intended to shift its observing strategy slightly to overlap with the same fields which Kepler had been looking at. NASA’s Spitzer Space Telescope was to have joined in the hunt too, in late June.
Kepler’s Microlensing Campaign Presently on Hold
It could have been the first microlensing survey directed at the same time from the ground as well as from space. The different vantage points could have enabled astronomers to research the potential microlensing planets much more easily than just utilising one or two ground-based telescopes. Andrew Cole, astronomer at the University of Tasmania in Hobart, Australia had stated that `there is a strong feeling like it’s Christmas morning and we were all set to unwrap a shiny new toy and then we had to put everything on hold owing to power outage or something’.
His team had scheduled to use a 1.3-metre telescope in Tasmania in order to track on microlensing alerts from Kepler. The start of Kepler’s microlensing campaign presently is on hold till engineers tend to get the telescope working again. It is presently about 120 million kilometres from Earth, which means that each message tends to take 13 minutes to reach Kepler and back. Days that are lost from the microlensing campaign would be difficult to make up later.
NASA’s director of astrophysics, Paul Hertz, had touted that the Kepler microlensing survey is a step towards the next big space telescope of the agency, the Wide-Field Infrared Survey Telescope, that is intended to do microlensing searches after it launches in 2020.
