It's been 15 years since Sleep's last album, Dopesmoker, whose 63-minute title track was all about marijuana. They surprised-released its long-awaited follow-up, The Sciences, today, which, probably not coincidentally, just so happens to be April 20.

The news came yesterday via Stereogum, who noted that it's on Third Man Records, the label owned by Jack White, and paid special attention to the fact that one of its six tracks (listed below) is called “Marijuanaut’s Theme.” Although it's their first full-length album since 2003, they put out a song called "The Clarity" in 2014, and guitarist Matt Pike said that its success helped lead to the songs on The Sciences.

"Sleep's at this level where we can't deny the fact that we need to be playing shows and making another record," he told Loudwire in 2016, "because it's been 20-something years and we did really good on the single we made."

The band just wrapped up a week and a half's worth of dates in the Midwest, but will return in June for a longer jaunt through North America. In between, Pike will be spending the end of April and May in Europe, playing the first half with his other band, High on Fire, and the second half with Sleep. You can see the itinerary for the remaining North American dates below.

They also revealed via Twitter that, in honor of 4/20, they've put out a green vinyl edition of The Sciences that can be purchased in select stores and at Third Man Records' online store.

Sleep, 'The Sciences' Track Listing

1. “The Sciences”
2. “Marijuanaut’s Theme”
3. “Sonic Titan”
4. “Antarcticans Thawed”
5. “Giza Butler”
6. “The Botanist”

Sleep 2018 North American Tour Dates

Jun. 5 – Seattle, WA – The Showbox
Jun. 6 – Portland, OR – Roseland Theater
Jun. 7 – San Francisco, CA – The Warfield
Jun. 8 – Los Angeles, CA – The Wiltern
Jun. 9 – Phoenix, AZ – The Van Buren
Jun. 10 – Albuquerque, NM – Sunshine Theater
Jun. 11 – Denver, CO – The Ogden Theatre
Jul. 22 – Washington, DC – 9:30 Club
Jul. 25 – Philadelphia, PA – Electric Factory
Jul. 27 – New York, NY – Brooklyn Steel
Jul. 28 – Boston, MA – Royale
Jul. 30 – Toronto, ON – The Danforth Music Hall
Aug. 1 – Chicago, IL – The Riviera Theatre
Aug. 30 - Sep. 2 – Cookeville, TN – Muddy Roots Festival

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