🥹

#Artemis #Nasa #Science #News

Visual demonstration of why Pi π is an irrational number. ⊙⁠.⁠☉

Gotta love math (⁠◍⁠•⁠ᴗ⁠•⁠◍⁠)⁠❤

#Math #Science #Numbers

It provides a rare, visible manifestation of subatomic processes that are otherwise hidden from direct human perception. 7/7

Today, this deep blue light is both a warning and a scientific tool. It signals the presence of intense ionising radiation, while also being exploited in particle detectors, nuclear reactors, and neutrino observatories. 6/

The phenomenon was first observed experimentally in 1934 and later explained theoretically, work that led to the Nobel Prize in Physics in 1958. Its explanation confirmed how relativity and electromagnetism operate in material media. 5/

This radiation produces the distinctive blue glow. The colour arises because Cherenkov radiation is strongest at shorter wavelengths, which are dominated by blue and ultraviolet light. 4/

While nothing can exceed the speed of light in a vacuum, light travels more slowly in materials like water.

When a charged particle surpasses this reduced speed, it emits a coherent shock-like electromagnetic wave, often described as an optical analogue of a sonic boom. 3/

This light is neither fire nor heat; it is Cherenkov radiation, a physical phenomenon that occurs when charged particles, such as high-energy electrons produced during nuclear fission, travel through a transparent medium faster than light can propagate within that same medium. 2/

When a nuclear reactor is switched on for the first time, an intense, almost hypnotic blue glow appears in the water surrounding the reactor core. 1/

#GottaLovePhysics #Physics
#science #technology #nuclearphysics

Merry Christmas
Feliz Navidad!
Joyeux Noël
Frohe Weihnachten
Buon Natale
Feliz Natal
Vrolijk Kerstfeest
God Jul
Glædelig Jul
Hyvää Joulua
Mutlu Noeller
Wesołych Świąt
Boldog Karácsonyt
Veselé Vánoce
Gleðileg Jól

Wishing you the best possible day. 🎄

#MerryChristmas #Navidad #Christmas

In this way, the new radio detection offers a compelling piece of evidence that 3I/ATLAS is a bona-fide interstellar comet, a visitor from beyond our Solar System behaving in line with our known cometary physics. 9/9

Further monitoring will help clarify whether the hydroxyl production is steady or variable, how extended the gas tail is, and how the object’s trajectory responds to non-gravitational forces. 8/

The observations were made on 24 October, shortly before the object’s perihelion, and after earlier unsuccessful attempts on 20 and 28 September. 7/

Although the detection alone does not shut down every alternative hypothesis, it significantly reduces the plausibility of a “probe” interpretation and underscores the comet-like nature of 3I/ATLAS. 6/

Earlier speculations had entertained the possibility of technological origin, fanned by social-media theories and even proposals by controversial astrophysicist Avi Loeb, but this molecular signature strongly tilts the balance toward a natural origin. 4/

Because 3I/ATLAS was approaching its closest point to the Sun, the geometry favored absorption of radio signals rather than emission, matching expected behaviour of an active comet rather than a transmitter. 3/

The signal consists of absorption lines of hydroxyl radicals (OH) at 1665 MHz and 1667 MHz, molecules commonly found when icy bodies near the Sun sublimate and generate a gaseous coma. 2/

Astronomers using the South African radio telescope array MeerKAT have detected a clear radio-frequency signal from the interstellar object #3I/ATLAS, bringing strong support to the idea that it is a natural comet rather than an artificial object. 1/

#news #science #astronomy

... (which will eventually survey ~20 billion galaxies) will systematically reveal a rich archaeological record of galaxy formation. 5/5

... namely its unusually high star-formation rate and multiple supernovae.

The discovery underscores that such stellar streams are likely ubiquitous around large galaxies and that Rubin’s unprecedented wide-field, deep-imaging camera... 4/

Astronomers interpret this as the shredded remnant of a dwarf galaxy that M61’s gravity ripped apart: this ancient encounter may have triggered fresh bursts of star formation in M61 and explains some of the galaxy’s puzzling properties, ... 3/

... and revealed for the first time a faint but very long stellar stream, a “tail” stretching about 55 kiloparsecs (≈180,000 light-years)—that had gone unnoticed despite decades of study. 2/

The @VRubinObs has already unveiled a stunning discovery: in its very first test image the giant telescope captured the well-known galaxy Messier 61 (M61), located in the Virgo cluster, ... 1/

#science #news #astronomy

👉 arxiv.org/pdf/2510.24836

These fresh observations highlight just how much we still don’t know about interstellar objects. 7/7

Though such behavior is not unheard of for comets, 3I/ATLAS nevertheless remains unusual: it shares comet-like activity while originating from outside our Solar System, and its composition and behaviour may inform us about conditions in another part of the galaxy. 6/

Concurrently, the object brightened significantly, by a factor of about five in the green band, which supports the idea that volatile release or fragmentation is ongoing. 5/

Based on the measured accelerations, the mass loss could amount to about 13 percent (or more) of the body’s total mass, assuming a typical gas-ejection speed near perihelion. 4/

... both radially and tangentially relative to the Sun.

The most plausible explanation is that 3I/ATLAS has been losing mass via outgassing, volatiles liberated by solar heating exert a thrust that nudges its path. 3/

While briefly hidden from view behind the Sun, it was monitored by spacecraft near Mars, and when it emerged, astronomers observed that its trajectory has shifted in a way that cannot be explained by gravity alone: the object shows non-gravitational acceleration ... 2/

The object known as #3I/ATLAS, the third confirmed interstellar visitor to our Solar System, appears to have undergone a subtle but telling transformation following its closest approach to the Sun. 1/