The Observatory — August 1, 2026

I · Now observing

A three-lobed asteroid, and the kilometre-wide moon that will weigh it

Astronomers turned a planet-hunter’s optics on a main-belt asteroid and found something no telescope had shown before. The object (44) Nysa appears to be built from three large lobes joined at two pinched necks, the first such body known.[1] In the same images they caught a faint companion about a kilometre across, a previously unseen moon now catalogued as S/2026 (44) 1.[1] The moon is the real prize, because tracking its orbit will weigh Nysa and settle what it is made of.[3]

lobes, joined at 2 necks

≈1 km

the new moon

≥170 km

moon’s orbit radius

≈20 mas

resolution achieved

01 What the images showed

The team observed Nysa with SHARK-VIS, a visible-light camera on one 8.4-metre mirror of the Large Binocular Telescope in Arizona, riding the telescope’s adaptive-optics system, on 15 February and 21 March 2026, with supporting images from a larger telescope in Chile.[3] The reconstructed pictures, sharper than the asteroid had ever been seen, showed two deep valleys wrapping its circumference, which the authors read as the necks between three distinct components.[1] In the residual light they isolated a faint point that moved with Nysa between the two nights, the signature of a bound moon.[1] The lead author, Kate Minker of Lowell Observatory, frames the result as a fork in the road, with the satellite as the way to choose between the branches.[2]

How a kilometre-scale moon settles what a 75-kilometre asteroid is made of. Tracking the satellite’s period and orbit radius gives the system mass through Kepler’s third law; mass over the modelled volume gives bulk density.

02 Why it takes exoplanet optics to see a lobe

At its distance from Earth the whole of Nysa spans only about seventy milliarcseconds on the sky, so splitting its lobes means resolving detail near twenty milliarcseconds, where a milliarcsecond is a thousandth of an arcsecond and an arcsecond is a 3,600th of a degree.[3] The atmosphere blurs an ordinary ground image to about one arcsecond, roughly fifty times too coarse, so the lobes can only be separated by adaptive optics, which flexes a mirror hundreds of times a second to cancel that blur and drive an 8.4-metre aperture to its natural diffraction limit of about twenty milliarcseconds in visible light.[3] The moon is harder still, roughly a milliarcsecond wide and drowned in the glare of a body far brighter, so pulling it out took the same contrast processing built to image faint planets beside bright stars.[4]

03 What the moon will decide

A bound satellite turns Nysa into a scale.[3] Kepler’s third law ties the moon’s orbital period and radius directly to the mass of the system, and mass divided by the volume of the shape model gives the bulk density, the single number the shape alone cannot supply.[3] A low density would point to a loosely bound rubble pile, or to a genuine contact trinary of three smaller bodies that drifted together and settled; a high, rock-like density would point instead to a single battered object merely sculpted to look tripartite.[1] The same measurement bears on how the wider Nysa asteroid family, one of the inner belt’s largest, came apart and reassembled.[2]

04 What to watch

The concrete next step is to recover the moon over several more nights and pin down its orbit, which yields the first well-constrained mass and density for Nysa.[3] A second, independent check could come from stellar occultations, the brief moments when the asteroid passes in front of a background star, whose timing across several sites would trace the multi-lobe outline directly if the campaigns are organised for the next apparition.[1]

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II · From the record

The Mars orbiter that flew on a rocket too small, and the price it set

India reached Mars on its first attempt with an orbiter that cost less than many feature films, and the interest of the mission lives in the arithmetic.[2] The Mars Orbiter Mission slipped into orbit on 24 September 2014, two days behind NASA’s MAVEN, having flown to the same planet in the same launch window for roughly one-eighth the price.[3] It got there on a rocket too weak to throw it straight at Mars, a constraint that forced the most inventive engineering of the flight.[3]

≈$74M

mission cost

≈8×

cheaper than MAVEN

perigee-raising burns

440 N

main engine thrust

01 A rocket that set the strategy

The mission was approved in August 2012 and flew in November 2013, a schedule of roughly fifteen months pinned to the narrow window when Earth and Mars align.[1] To hold that schedule and budget, engineers reused the spacecraft bus and subsystems from India’s earlier lunar orbiter, built the craft essentially single-string with little redundancy, and flew without launch insurance.[6] The only available rocket, the workhorse PSLV, was sized for Earth-orbit payloads and could not inject the 1,337-kilogram craft onto a Mars trajectory in a single push.[3]

The rocket set the strategy. Too small to inject the craft toward Mars directly, the PSLV left the orbiter in a low Earth orbit; six burns of its own 440-newton engine, each fired at the low point where a burn does the most good, walked the far point outward until a final push sent it to Mars.

02 Walking the apogee out, then relighting cold

So the orbiter was parked in a low Earth orbit and made to climb in stages.[3] Over six burns of its 440-newton engine, each fired at perigee, the low point of the orbit, it walked its far point outward through roughly 40,000, 71,600, 119,000 and finally about 193,000 kilometres before a trans-Mars injection burn on 30 November 2013 sent it out of Earth’s grip.[3] Firing at perigee is the efficient choice because a burn adds the most energy where the craft is moving fastest, so the engine buys distance in installments rather than all at once.[1] Then came a 300-day coast with the engine cold. On 22 September 2014 controllers ran a 3.968-second test firing to prove it would relight, and two days later the full orbit-insertion burn ran 24 minutes and 14 seconds at about 1,098 metres per second, consuming 249.5 kilograms of propellant.[4] The one-way radio delay was 12.5 minutes, and part of the burn happened while the craft was hidden behind Mars, so it fired on an onboard sequence with no one able to intervene.[4]

03 Why it mattered, in numbers

Because the two orbiters flew to the same planet in the same window and both arrived, they form a rare clean comparison.[3] The Indian mission cost about 4.5 billion rupees, near 74 million dollars, against a lifecycle cost of about 582 million for MAVEN, roughly eight times as much.[6][2] The honest asterisk is scope: the Indian craft carried only a 15-kilogram, five-instrument payload billed as a technology demonstrator, while MAVEN flew a heavier science-grade suite to study the upper atmosphere, so part of the gap is buying less science rather than pure thrift.[1] Even allowing for that, the benchmark held, since a craft designed for six months kept working until 2022, some seven years in orbit, and the same agency repeated the feat with a Moon landing in 2023 for around 75 million dollars.[6] One tally at the time counted 43 Mars attempts with 23 failures, a success rate near 40 percent, and India cleared it on the first try, with the fair caveat that Europe reached Mars orbit on its own first attempt in 2003.[5]

04 Echoes today

The fingerprints are visible in every frugal deep-space plan: staging orbital energy to fly heavy payloads on modest rockets, accepting single-string risk on a demonstrator, and turning a low-cost success into political capital.[6] In India that last effect was concrete, feeding the case that opened the national space sector to private companies at the end of the decade.[6]

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