Particle physics experiments

“Wonderful”: researchers from the Mass. prepare for experiments with the new James Webb Space Telescope

“It’s really wonderful to see how much effort has gone into this,” said Daniel Eisenstein, chair of Harvard University’s astronomy department. “It’s great to see what he’s going to do, but it’s also really great to look back at what has already been achieved.”

Eisenstein said he is interested in how galaxies formed and how they “build up over time”, comparing galaxies to understand their evolution. For days at a time, he said, as part of his research, the telescope will point to certain points in the sky “to build up the signal to observe very faint objects.”

Researchers hailed Webb as the successor to the revolutionary Hubble Telescope. The main difference between the two telescopes is that Webb will capture information via infrared light, rather than visible light, and allow researchers to collect information with greater sensitivity.

NASA says the telescope will actually be able to see farther in time because ultraviolet and visible light emitted when the very first galaxies formed now arrives as infrared light, having been stretched or “shifted towards the red” by the expansion of the universe.

“Different telescopes are designed to observe different parts of the spectrum,” said Edo Berger, professor of astronomy at Harvard University. Webb “is significantly larger than Hubble, and it’s optimized for observations, very detailed observations” in the infrared spectrum, rather than the visible spectrum.

Berger plans to use the telescope to study kilonova explosions, which are neutron star collisions. He explained that neutron stars are dense objects that “weigh about one and a half times the mass of the sun but are packed into a sphere about the size of the city of Boston.”

“What James Webb will do for us, in particular, is that he will allow us to study these collisions in much greater detail and [at] far greater distances than they have been able to do in the past,” he said.

Two others scientists from separate projects will use the telescope to study exoplanets — planets that orbit stars other than the sun — and their atmospheres.

Sara Seager, professor of physics and planetary sciences at the Massachusetts Institute of Technology, said she would use the telescope to compare when an exoplanet is in front of a star and when it is not.

“Comparing these two measurements, they’re going to be a wee bit different because when the planet…in front of the star is blocking out some of the starlight, in particular, the atmosphere is blocking out some of the starlight. , and so we can tell what’s in the planet’s atmosphere,” said Seager, whose team is studying three exoplanets.

Mercedes López-Morales, astrophysicist at the Center for Astrophysics/Harvard & Smithsonian, will use spectrography to better understand the atmospheres of exoplanets.

“Basically, if you have a water molecule, that water molecule is not going to leave [it] pass through light of a given color. … What we do is when we receive that light, we look at the different colors and we look for the missing ones,” López-Morales said. “That’s exactly how we know what molecules…the planet’s atmosphere has.”

Harvard astronomy professor Karin Öberg will use the telescope to identify specific molecules in five planet-forming “discs” around young stars.

The researchers will begin work once the telescope is fully operational — in about five months or so, Berger said.

López-Morales said she was excited about the potential to learn important new information about the universe.

” I do not know what [our observations] going to show us now – because we don’t have them yet,” she said. “But they might show us things that we didn’t even think of, and that [in] itself – this is how scientific breakthroughs happen.


Matt Yan can be contacted at [email protected]