Though ratings slipped slightly this week, The Big Bang Theory continued to bring in the laughs with “The Higgs Boson Observation.”

This week’s episode of The Big Bang Theory was watched by 14.23 million viewers, which once again brought the show in first in its time slot. Though overall numbers were down, the show lost less than a million viewers from last week.

“The Higgs Boson Observation” introduced a new potential obstacle in Leonard and Penny’s currently on-again romance. Hoping to unearth a brilliant childhood discovery, Sheldon hires Alex, an attractive graduate student (Margo Harshman) to read through his old journals and act as his assistant. Though at first Amy worries about Alex coming on to Sheldon, it is Leonard with whom Alex seems to be feeling the chemistry, so a nervous Penny is left to defend her territory.

Meanwhile in outer space, Howard gets cabin fever on the International Space Station and pulls a full-on crazy Wolowitz when his shuttle back to Earth is delayed. Luckily for Wolowitz, “The Re-Entry Minimization,” airing Oct. 18, should solve his anti-gravity issues – even if coming back down to Earth presents a few more problems than he expected. CBS says:

When Wolowitz returns from space, he doesn’t get the hero’s welcome he expected. Meanwhile, Game Night turns into a battle of the sexes.

The Big Bang Theory airs Thursdays at 8 p.m. on CBS.

What did you like about ‘The Higgs Boson Observation’?