The gravity from the foreground star magnifies the light from the star behind it. This looks at how light bends due to a strong gravitational field, which happens when a star momentarily aligns with a more distant star, as seen from Earth. The new white dwarf exoplanet was found with what is known as the microlensing detection method. Individual objects in the asteroid main belt and Kuiper belt (a disc in the outer Solar System) are likely to survive the SunвЂ™s demise, but some will be moved by gravity by one of the surviving planets towards the white dwarfвЂ™s surface. The link between exoasteroids and exoplanets also applies to our own Solar System. Although in the system being discussed in the paper, current technology does not allow us to see any exoasteroids, at least now we can piece together different parts of the puzzle of planetary fate by merging the evidence from different white dwarf systems. Our discovery finally provides confirmation of this. Hence, exoasteroids have been long assumed to be evidence that exoplanets are there too. For exoasteroids to get so close to a white dwarf, they need to have enough momentum imparted to them by surviving exoplanets. After that, there wouldnвЂ™t be enough radiation to sustain anything.ДЄlthough planets orbiting white dwarfs have been difficult to find, what has been much easier to detect are asteroids breaking up close to the white dwarfвЂ™s surface. So could any life survive this transformation? A white dwarf could power life on moons or planets that end up being very close to it (about one-tenth the distance between the Sun and Mercury) for the first few billion years.

If so, that is additional evidence for assuming that Jupiter, and Mars, will make it. Moreover, the margin of error in the position of this exoplanet could mean that it is almost half as close to the white dwarf as Jupiter currently is to the Sun. But with our discovery of this new exoplanet, we can now be more certain that Jupiter really will make it. Jupiter, and its moons, have been expected to survive, although we previously didnвЂ™t know for sure. That means the Sun will (probably) engulf Mercury and Venus, and possibly the Earth вЂ“ but we are not sure. When the Sun eventually becomes a red giant, its radius will actually reach outwards to EarthвЂ™s current orbit. We believe that this exoplanet only just survived: if it was initially closer to its parent star, it would have been engulfed by the starвЂ™s expansion. A starвЂ™s transformation into a white dwarf involves a violent phase in which it becomes a bloated вЂњred giantвЂќ, also known as a вЂњgiant branchвЂќ star, hundreds of times bigger than before.

This new exoplanet, which we discovered with the Keck Observatory in Hawaii, is particularly similar to Jupiter in both mass and orbital separation, and provides us with a crucial snapshot into planetary survivors around dying stars. In our new paper, published in Nature, we report the discovery of the first known exoplanet to survive the death of its star without having its orbit altered by other planets moving around вЂ“ circling a distance comparable to those between the Sun and the Solar System planets. Fortunately, we are now filling in the gaps. This lack of data paints an incomplete picture of our own planetary fate. In fact, of the over 4,500 exoplanets that are currently known, just a handful have been found around white dwarfs вЂ“ and the location of these planets suggests they arrived there after the death of the star. The feeble radiation from white dwarfs makes it difficult to spot exoplanets (planets around stars other than our Sun) which have survived this stellar transformation вЂ“ they are literally in the dark. So which planets in will survive the death of the Sun? One way to seek the answer is to look at the fates of other similar planetary systems. This transformation will involve a violent process that will destroy an unknown number of its planets. We know that the Sun will eventually become a вЂњwhite dwarfвЂќ, a burnt stellar remnant whose dim light gradually fades into darkness. By Dimitri Veras, Associate Professor and STFC Ernest Rutherford Fellow of Astrophysics, University of WarwickД¬oventry (England), Oct 14 (The Conversation) How will the Solar System die? ItвЂ™s a hugely important question that researchers have speculated a lot about, using our knowledge of physics to create complex theoretical models.

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