Rubin Observatory Spots an Asteroid That Spins Fast Enough To Set a Record

Astronomers using the Vera C. Rubin Observatory have discovered a record-setting asteroid, known as 2025 MN45, nearly half a mile wide and spinning once every 1.88 minutes -- the fastest known rotation for an object of its size. "This is now the fastest-spinning asteroid that we know of, larger than 500 meters," said Sarah Greenstreet, University of Washington astronomer and lead author of the study. The findings have been published in the The Astrophysical Journal Letters. GeekWire reports: 2025 MN45 is one of more than 2,100 solar system objects that were detected during the observatory's commissioning phase. Over time, the LSST Camera tracked variations in the light reflected by those objects. Greenstreet and her colleagues analyzed those variations to determine the size, distance, composition and rate of rotation for 76 asteroids, all but one of which are in the main asteroid belt between the orbits of Mars and Jupiter. (The other asteroid is a near-Earth object.)

The team found 16 "super-fast rotators" spinning at rates ranging between 13 minutes and 2.2 hours per revolution -- plus three "ultra-fast rotators," including 2025 MN45, that make a full revolution in less than five minutes. Greenstreet said 2025 MN45 appears to consist of solid rock, as opposed to the "rubble pile" material that most asteroids are thought to be made of. "We also believe that it's likely a collisionary fragment of a much larger parent body that, early in the solar system's history, was heated enough that the material internal to it melted and differentiated," Greenstreet said. She and her colleagues suggest that the primordial collision blasted 2025 MN45 from the dense core of the parent body and sent it whirling into space.

That's not a knife

[quenda]

nearly half a mile wide and spinning once every 1.88 minutes -- the fastest known rotation for an object of its size.

May I present this pulsar [wikipedia.org]
spinning at 42,981 revolutions per minute , with radius "under 16 km", so I assume somewhat larger than 500m.

Re:

[MarkHughes4096]

People in the 70's did that quite often, They even made a song about it, It was so popular that upon trying it they often demanded to do it again...

Re:

[Viol8]

An almost limitless source of energy if there was any feasible way of harnessing it. Though I imagine a number sci fi authors have probably already come up with some ideas.

Re: That's not a knife

[BigEddieD]

In my opinion, we should be able to draw similar energy from the rotation of the earth, combined with our magnetic field. This is also probably the explanation for UFO sightings - they could care less about us, but they need a class M planet (one that can support life) in order to recharge their engines. By collecting excess energy using the combo of the magnetic field and earth's rotation, they are able to refuel at any system containing a similarly configured planet.

Re:

[gtall]

""This is now the fastest-spinning asteroid that we know of, larger than 500 meters,"

Please point out the word you do not understand. Hint: It spells "asteroid".

Re:

[tsqr]

""This is now the fastest-spinning asteroid that we know of, larger than 500 meters,"

Please point out the word you do not understand. Hint: It spells "asteroid".

That's a quote from TFA in TFS. BeauHD's opening paragraph in TFS is where the word "object" is inappropriately used. Odd, because as we all know, screwups by Slashdot editors are vanishingly rare.

Re:

[OrangAsm]

I prefer objects on which I can sit and spin.

Fast enough to set a record

[MarkHughes4096]

But not fast enough to play one :)

I don't know about you..

[rossdee]

but my records spin at 33 and a third RPM

I'm not saying...

[greytree]

I'm not saying it's alien DJs, but...

Fast and large enough for a Bernal sphere

[n2hightech]

The outside would have about 1.5 g acceleration.Hollow out the interior leaving a nice thick external shell for structure and shielding we get a perfect 1 g habitat. with lots of space. All we need is for SpaceX to haul up one of Boring companies drilling machines presto instant space colony.

Re:

[sabbede]

And what makes you think that hasn't already happened? These must be survivors of the 5th planet, which the Martians destroyed.

Minor correction:

[Gravis Zero]

nearly half a mile wide and spinning once every 1.88 minutes -- the fastest known rotation for an object of its size*.

* Besides your mom on a stripper pole.

Max spin is based on density

[FeelGood314]

Assuming only gravity holds the object together. Or another way to put it, the minimum orbital time is dependent only on the density of the object not its size. For example loose iron can only spin at once every 2 hours.
So this object must be solid and could not have formed spinning this fast.

fast enough for a record

[groobly]

Is it faster than 78 rpm?