Astronomers who live in Washington and follow the science of exoplanets are getting antsy because now the race is on for the most dazzling exoplanet yet to be discovered.
“We’re still just looking,” said Michael Kosterlitz, the director of the Center for Astrophysics at the National Air and Space Museum. “We’re still very much looking.”
Kosterlitz and other scientists from around the country began planning their biggest initiative yet last week to sample the next discovery of an extrasolar planet.
It’s a big idea. What if a team of astronomers had already found an enormous planet that — after years of searching — finally was located. Then, on Earth, we heard the amazing news that we were just 30 light years from a planet the size of Jupiter that has no atmosphere — and most likely could be ready to come into view with a long-range telescope. We’re now counting down the days before the planet could show up in a map — and that has scientists getting concerned about the potential impact that event could have on their efforts to confirm the existence of alien life on other worlds.
Several people who participated in the discovery of exoplanets over the past few years say it’s difficult to let go of them and move on.
“People ask us, ‘How many Earth-size planets are there in the universe?’ It feels like 20 or 30 billion,” said Juan Nuciforo, a graduate student at the Johns Hopkins University.
Nuciforo is part of a group that began collecting information about exoplanets in 2008 and has already discovered several small planets beyond our solar system. Two of them are under consideration for being considered for further study by NASA.
On March 4, astronomers in two telescopes at the National Science Foundation headquarters announced they had found the smallest known planet beyond the solar system, about twice as big as the Earth and located about 40 light years away.
The group is looking for an Earth-size planet in the same region so that it could be confirmed as the right exoplanet to characterize beyond Earth.
“It’s hard to just close it off,” Nuciforo said. “We’ve put a lot of work into it.”
That planet’s discovery was hailed as a milestone in the detection of Earth-like worlds. This most recent discovery may also be an important turning point.
“It is very exciting to think that the OSIRIS-REx mission could arrive at this object within a few years,” said Gavin Hulme, the team leader of the OSIRIS-REx mission at the Southwest Research Institute in San Antonio.
“ASTRO data could be extremely important in determining the precise location of the planet and determine whether it has characteristics that would make it habitable or not,” Hulme said.
The OSIRIS-REx mission, for short, launched on Sept. 2, 2013.
When that spacecraft arrives in July 2023, astronomers hope to see the unknown planet while observing it from an altitude of about 17,000 feet. The spacecraft will wait for close to the planet and then activate a suite of instruments with a narrow-angle spectrograph.
The scientists will use that to identify chemical signatures in the planet’s atmosphere that might show up as gases from the atmosphere of the parent star.
“Very few features in the infrared spectrum can be detected,” Nuciforo said. “So we are optimistic about getting a really good atmospheric picture.”
The problem is that the next closest planet to the OSIRIS-REx mission is quite far away — which makes it even harder to identify.
“When you’re going into dark territory, you’re doing a search for stuff that’s invisible,” said Jim Green, NASA’s planetary science division director, in a NASA video about the discovery of the smallest exoplanet.
Kostelnik said he’s optimistic that when the OSIRIS-REx spacecraft reaches the target planet, its status as a previously undiscovered world will become known.
“Our job is to get the science in there,” he said. “From there, science takes over.”