Hubble may have discovered the closest known intermediate black hole

We remember that in 2020 the Swedish Academy awarded the Nobel Prize in Physics to Andrea Ghez and Reinhard Genzel ” To discover a massive compact object at the center of our galaxy Exact wording is important, because while the majority of AstrophysicistsAstrophysicists I think this object is already Giant black holeGiant black holewhich did not contradict, quite the contrary, the observations of the collaboration Event Horizon TelescopeWe don’t have a definite proof yet, but it’s pretty close. In general, it is reasonable to believe that this evidence will come from the study of gravitational waves.

The two researchers and their team came to the discovery of this compact object through a study of more than a decade movementsmovements The stars are near the center milky waymilky wayIt revolves around a mysterious wave source radioradio His name is Sgr A*. So this source happens to be associated with a distribution MassMass compact in amountamount from according to equationsequations affiliate general relativitygeneral relativity make one Black holeBlack hole Just over 4 million solar masses. In fact, this object does not radiate on its own and Electromagnetic wavesElectromagnetic waves which we find out where it comes from ThemeTheme about this a stara star compact.

This simulation shows the orbits of a small group of stars located near the supermassive black hole at the center of the Milky Way. During 2018, one of these stars, called S2, passed very close to the black hole and has been the subject of an intense campaign of observations using ESO’s telescopes. Its behavior was consistent with the predictions of Einstein’s general theory of relativity – but inconsistent with Newton’s theory of gravity. © ESO, L. Calçada, spaceengine.org

Universal law for the size of black holes?

In fact, it has been believed since the late 1960s, and observations have only reinforced this hypothesis, that there are supermassive black holes at the cores of all large galaxies containing at least a million solar masses. We also note that the mass of the detected black holes is often proportional to the mass of the black holes galaxygalaxy hosts.

We also know that in the Milky Way there are many black holes weighing about ten solar masses each, for the most part. Therefore, some researchers wondered whether the law of proportionality observed in large galaxies could not also be valid for dwarf galaxies and globular clusters.

If so, there must be so-called intermediate-mass black holes containing approximately one hundred solar masses and one million solar masses. We’re tracking these objects and know of some extragalactic candidates like 3XMM J215022.4−055108, telescopetelescope Hubble discovered in 2020, and HLX-1, identified in 2009. They reside in dense star clusters on the fringes of other galaxies. Each of these potential black holes has a mass of tens of thousands of sunssuns and some clusters, where they have been observed, may have been the nuclei of now-extinct dwarf galaxies, but they have been dislocated tidal forcestidal forces of the galaxies they passed at a very close distance.

Today, as an article published in Monthly Notices of the Royal Astronomical Society Led by a team of researchersastronomerastronomer Eduardo Vitral from Space Telescope Science Institute From Baltimore, Maryland in the United States, the telescope remains HubbleHubble which provides observations that intermediate black holes do indeed exist. Above all, these observations relate to the Milky Way as they relate to the motions of stars in the Milky Wayglobular clusterglobular cluster Messier 4 (M4) which is only about 7,000 light yearslight years the solar systemsolar system.

This video begins with a wide view of the magnificent central parts of the Milky Way. We are approaching the constellation of Scorpio. Near its nearest star, Antares, is the Messier 4 globular cluster, one of those star systems closest to Earth. The detailed images of the cluster at the end of this video are from the WFI camera on the MPG/ESO 2.2-meter telescope at ESO’s La Silla Observatory in Chile, and finish with a close-up of the power plant in the area produced by NASA. / European Space Agency’s Hubble Space Telescope. © ESO-ESA-Nasa, Digitized Sky Survey 2, Nick Risinger (skysurvey.org)

The closest globular cluster to the Sun

call again NGCNGC 6121 and located at constellation Scorpioconstellation ScorpioM4 is actually the closest globular cluster to the Sun. It was discovered by the Swiss astronomer Jean-Philippe Louise de Chiseau in 1746. Eduardo Vitral and his collaborators now suggest that it contains a compact object with about 800 solar masses. Again, due to the motion of the stars around it, it must be a black hole and in this case an intermediate mass black hole.

After more than 12 years of observations, astrophysicists have come to this conclusion by ruling out other alternative hypotheses for a compact star, such as the concentration ofNeutron starsNeutron stars or Stellar black holesStellar black holes that producedCollapsesCollapses stars. the above AccuracyAccuracy Because the images taken by Hubble were essential to accomplishing this feat by allowing observation of point stars in orbit and accurate measurements of their positions and gearsgears While the cluster contains a large number of stars in a size with a radius of only 35 light years.

In a statement from NASANASAEduardo Vitral explains on this subject: We are convinced that we have a very small area with a lot of concentrated mass. It is about three times smaller than the denser black mass we’ve found before in other globular clusters. The area is much more compact than we can breed with Numerical simulationNumerical simulation When we think of a group of black holes and neutron stars and white dwarfswhite dwarfs separate in the center of the cluster. They are not able to form such a compact focus of mass. »

The same press release also states: Grouping closely related objects dynamically may be unstable. If the object was not a single intermediate-mass black hole, it would take about 40 smaller black holes in just a tenth of an area of ​​light to produce the observed stellar motions. The consequences are that they will be sucked in and/or kicked out in an interstellar pinball game. »

Presentation of the discovery made by Hubble of M4. For a more or less accurate French translation, click on the white rectangle at the bottom right. The English translation should then appear. Then click the nut to the right of the rectangle, then click Subtitles and finally Subtitle Automatically. Choose “French”. © NASA’s Goddard Space Flight Center; Principal producer: Paul Morris. Computer representation of stellar motions at the core of M4: Mattia Libralato (AURA/STScI for ESA)