While the messages wouldn't necessarily be restricted to 140 characters, a study suggest, ET is more likely to send out short, directed messages than continuous signals beamed in all directions.
"This approach is more like Twitter and less like War and Peace," Dr James Benford, a physicist and president of Microwave Sciences in the US, said.
His twin brother, Gregory, an astrophysicist at the University of California, said: "Whatever the life form, evolution selects for economy of resources.
"Transmitting signals across light years would require considerable resources."
The brothers claim scientists involved in America's Search for Extra-Terrestrial Intelligence, or SETI, have been taking the wrong approach for five decades.
They said alien signals would not be blasted out in all directions but narrowly directed in the one-to-10 gigahertz broadband signal range and SETI's broad sweeping search of the galactic plane could leave many days when brief Twitter-like flashes of "here we are" from alien civilisations go undetected.
Meanwhile, it's been revealed more than 100 planets of a similar size to Earth have been found in just the past few weeks.
The discovery was made by space telescope Kepler, which has been scanning the skies for planets orbiting stars since it was launched in January last year.
Scientists now think there are likely to be around 100 million planets in the Milky Way that harbour the right conditions for life.
They also expect to be able to identify around 60 of these habitable Earth-like planets within the next two years.